Alright guys... this is a huge post so I'm not even sure if it will fit in one post of if I'll have to spread it out.

I'll post it here... have a read let me know if its what you're after and if there is anything to add/change

Enjoy

This Is a basic “How To” on engine assembly I wrote. I left the invitation open for anyone to add to or comment on... And with the contributions of the following people, this is the finished product. Special thanks to:

Matt Read (TheMiniMan)
Kevin G. (drmini in aust)
GT mowog (Burt Munro )
Rodney(um.... Rodney?)
mini-dunger (sorry mate, don’t know your name either)
Morris1100
David Rosenthal
David (850man)
Simon K.
And everyone else who asked the questions to get us all thinking

This is a “how to” for engine assembly only. It is not specific to any model of A series in particular, just a general run down on the procedures involved. It is not a guide for a performance build (though most of the steps are the same), it is just a guide for a genneral rebuild. This does not cover intial start up, run in, disassembly or anciliaries.

I hope you all find it useful, or at the least an interesting read.

Alex K.





A Series Engine Assembly



A few things before I get started. Rebuiding your own engine is rewarding, enjoyable (for most of us most of the time) and a mildly challenging experience. However, as GT mowog quiet rightly pointed out, if you have never undertaken a rebuild before it is a good idea to get someone who has to do it with you. There is no substitute for experience. Rebuilding an engine is not for the faint hearted and if in doubt, don’t. Get an experienced person to walk you through it to make sure you don’t make any mistakes.

GT mowog’s suggestion was, if its your first time tackling a rebuild get a running engine (one in ok to reasonable health) and strip it, re assemble as though you were doing a full rebuild and re-gasket it. Its a good chance practice all your measuring, cleaning, and assembly skills, and because it was running fine before hand, (and all the parts) fit you should be able to re assemble and drive without issue.

Another valuable piece of advice is making sure your work space is clean and spotless. Make sure you are clean and spotless. And as Rodney quiet rightly points out, make sure your tools are clean, a lot of people over look cleaning their tools. If you’ve got long hair, tie it up and put it in a hair net or under a cap or something.... you don’t want it falling out into anything (ask me how I know that )




Tools


As well as you’re normal tools (screw drivers, files, taps, pliers etc.) there are a few special tools and pieces of measuring equipment you will need. These include:

Micrometers: ( 0 -1” .... 1-2”....2-3” but at the very least a set of 1-2” micrometers. This is an imperial motor, so buy imperial Micrometers).

Feeler Gauges

Dial Gauge (and stand)

Plastigauge (strongly recomended)

A ground straight edge (decent steel rule might get you by)

Torque Wrench (1/2 drive that will cover a range from 25ft/Ibs to 150ft/Ibs)

Imperial Socket set

Piston Ring Compressor

Valve Spring compressor (or a work shop press)

And if you can afford it, get an engine stand... they make life so much easier

OH and don’t forget the most useful tool of all... a workshop manual appropriate for your motor.




Just A Couple More Points Before We Start



There a few more does and do nots worth pointing out at this stage too.

GASKETS

DO NOT try and reuse old gaskets. Gaskets are a single use item. You can (in some instances) get away re-using head gaskets, but its really only the BK450, Copper and Stainless gaskets (as made by Cometic) that you would even think about re-using. Aluminium head gaskets are well and truely single use only (these are the silver cardboard looking ones.. incidently, as far as sealing goes, these are amoung the best on the market for general use).


FASTENERS

Most of the fasteners in your motor should be reusable (obviously if a nut or bolt is stripped... just replace it... you’ll be thankful you did). GT mowog, and myself both prefer to replace every nut and bolt, just so that the whole thing goes together the way you would expect a new motor to and looks nicer.... this is not mandatory... just a personal thing...

It is adviseable to buy new fastners for items like head studs (and nuts), Main bearing caps, big end caps just because of the nature of their purpose. Normal nuts and bolts have a relitively low range of elasticity,, that is, they stretch easy and do not return to original size.... so in areas of the motor as mentioned above where they have critical torque preloadings placed on them, special nuts, bolts and studs are used to ensure that they don’t just keep stretching.... However, they do still have a limit to the amount of times the can be used, and if they have at any point been tightened beyond their yeild, they loose all elasticity and will not give a correct preloading..... IN SHORT If you don’t know their history, replace them.... ESPECIALLY ROD BOLTS conisder for a second how fast the piston is moving even during normal driving.... now think about the damage that will occure if the rod cap let go.... I’ll let you work it out It pays to pay for new rod nuts and bolts.


COOLING SYSTEM AND OIL

Buy a new oil pump and water pump. They wear out, so don’t mess around cleaning out and fitting old ones only to have them fail a week later.

Another pair of good points that 850man and GT mowog raise, is the improtance of getting your radiator and heater core serviced and hot tanked... Your heater core and radiator are part of the cooling system that run through the engines water pump and water jacket.. so whats the point in getting the scale in your water jacket chemically removed if your just going to fill it back up with muck out of the radiator and heater?

With the gearboxes, they share oil with the motor.... so treat it as part of the motor. PULL IT APPART AND CLEAN IT OUT with the same vigor as your motor. As 850man says, its impossible to get these propperly clean while they are together.

This is also a great chance to inspect your gear box and replace any worn parts (1st / 2 nd selector fork wears out pretty quick... so do the baulk rings.. and layshafts in pre A+ boxes).

The way I like to put it is, would you pour old oil into a new motor and throw a fist full of swarf in there? No. So clean your gearboxes out.

Another thing too, if your engine has an oil cooler, I like to replace these during the rebuild. Its near imposible to make sure they’re clean inside so just replace them rather than run the risk. They cost a littlle over $100 on ebay brand new.


*TIP*
After you rebuild your engine and get it running, run water in cooling system it for the first 500km (or til the first oil change) and then flush it and refill using coolant... most coolants are corrosive, so if you have any cooling leaks you wouldn’t want them ruining your paint



*NOTE THIS QUOTE*

At least one of those two points will have caught someone reading this out at least once... Take it from me... it sucks learning this the hard way.




Data Logging


One thing I do with everyone of my engines is log everything in a spec sheet as I measure it, torque, time it... And yeah I do have Cbsesive Compolsive Disorder but in all seriousness, it comes very handy later down the track if you need to remember what it was when you put it together.




Block Prep

DO NOT UNDER ANY CIRCUMSTANCE PLACE BLOCK ON ANY SURFACE EXCEPT MAYBE CARDBOARD OR A SOFT PILE OF RAGS WITH THE GASKET FACE FACING DOWN.


You might think I go overboard with some of my deburing and block prep... but I have a reasons for it.....

1. A burr kicked up the wrong way can stop two faces mating properly
2. A burr in the cumbustion space can cause pinging
3. Not countersinking a threaded hole “can” create a place for a bolt (or stud) to shear easer AND may stop two faces mating properly

Any thing with a thread in it, I just run the appropriate tap thru it to clean it up just incase. It just give the engine that "brand new" feeling while you're putting it together



1. Before you clean the block inspect it. Starting on the deck, have a look at your stud holes. I counter bore them using a drill just 1-2mm larger in diametre than the hole... if you use a proper counter bore you will end up with the hole at the surface too large. All I seek to do is remore the first 3-4 threads so that when the head is torqued up, its pulling from below the surface. This stops you pulling the gasket surface up around the stud hole and creating a high spot and potential leak point. I then lightly counter sink the stud holes, and deburr all the other holes... don’t go overboard deburring, you’re just taking the sharp edge off... on some engines (other than A series) you’ll have problems if you go crazy with and countersink these holes as some may come past the firing rings.


2. Using an oil stone, I rub down the deck using a figure 8 pattern. Make sure you cover the whole deck evenly, and apply even pressure. Then using a straight edge and feeler gauges, check it for flatness. I do it like this..... run the straight edge along the block, down the center then try and poke a feeler gauge under it ANYWHERE... you're looking for as close to absolute flatness as possible and no more warpage than the allowable amount (again check manual). Repeat this procedure 5mm from either edge, then on a diagonal then the other diagonal

3. At either end of the block, (transfer housing face and water pump end) give it the same treatment, deburr all holes and give it a rub down with the oil stone. Caution with the recess for the oil pump, do not countersink any of these holes as you may affect the way the pump seals... I’m probably parnoid, but I don’t do it and I’ve never had a problem

4. Flip the block over. Same deal, deburr, stone. WITH THE MAIN CAPS AND HOLES FOR THE MAIN CAPS IN THE BLOCK, make sure the dowell holes are countersunk at least 0.5mm (0.020”)... In ANYTHING where dowells are used as a RULE the dowell holes must be counter sunk. This eleminates (or greatly reduces) a shear effect that can take place. Also have a look at the edges of the bearing tunnels and make sure there are no burrs... if there are, just polish out the bur with a needle file being careful not to touch the area where the shell sits. While you’re down here, you may like to deburr the bottom of the edge of the bores.... the reason I do, is so when I’m cleaning I don’t cut my precious hands ... I then run the stone over the gasket face on the sump rail just to clean it more than anything.

*TIP*
While you are deburring, Simon K. Suggests that you debur your timing sprockets and pull apart your oil pump and debur it too... that's deburr not chamfer

*TIP*
A trick GT mowog suggests checking the oil drillings for the main bearings line up at this point. He does this by cleaning the old bearing shells and placing them in the block and seeing if the holes line up with the holes in the shells. If they don’t, he suggests just filing the hole so that the hole will supply oil to bearing (within reason...).



Block Clean Up

While your cleaning, as David Rosenthal and GT mowog correctly point out, check your cam bearings (if they were installed by the machining shop)... and as soon as possible (after cleaning) check your cam shaft for fit with generous oil on the journels. Also check that the oil holes line up.


1. Clean out oil ways and water jacket on block. I use special nylon pipe cleaners for all the drillings. I use Kero in my parts cleaner, other people use Disease-al or even petrol, your choice use what makes you happy. Be thorogh and take your time. If you’ve had your block chemically cleaned do not assume it doesn’t have sediment sitting in places, be just as thorough. Let the “cleaning agent of your choice” drain out as much as posible. Don’t forget to clean out all the threaded holes too.

2. Place in engine stand (or on a clean bench). Using a clean rag whipe of any kero you may have missed. Then, the fun part. Cleaning all the honing residue out of the bores *YAY* so what I do here is using ya mums finest paper towells, I put a bit of clean engine oil on them and scrub the bores.... after about 10 seconds you’ll have a look at the paper towell and see its black as the ace of spades. That black stuff is Carborundum... its what the honing stones are made out of and is incredibly abrassive.... so GET RID OF IT ALL or it will turn your oil into lapping paste and wear your honing out in minutes maybe hours Don’t stop scrubing till the towells are coming out as clean as they went in.. THEN repeat using Thinners instead of oil. You might ask why I don’t do it dry? Well, have a look for yourself, get it as clean as you can dry, then oil one up and rub it again and see how clean they really are... you’ll be suprised....

A lot of people prefer to clean out the bores using soapy water, infact, its what Grant Piston Rings suggest (and reading between the lines Matt Read uses this method as well). Nothing wrong with this method, just make sure you IMEDIATELY srpay them down with WD40, Linox, CRC, oil any thing that will stop it rusting.

3. Clean and dry all bearing tunnels. Do not leave any oil or kero on the face of these.




MEASURING TIME, LETS GET STARTED


A couple of things here. When I wrote this originally, I totally forgot that Small bore engines and Cooper S blocks have the side tappet covers. Thankfully, Rodney pulled me up on it (thanks mate ). So while your reading this procedure, I’ll make notes where things are done in a different order for side cover style motors.

Also, if you have had any plugs out of the motor, put them back in before you start. Its just easier this way.
Alright, lets get on with it



Clean crank up with the same vigor you attacked the block with. I use the same nylon pipe cleaners in the crank oilways.. and I made a tap (you might be able to buy one) for cleaning the crap out of the threads on the ends of the crank.

Measure up the journels. Please do this with a micrometer. Please check that it has been zero’d correctly.

1. Measure the journels on at 4 planes (think union jack pattern) and log the sizes so you:
a) know what size it was and
b) can check for obvious ovality.

Be careful around the oil holes our you might end up reading 0.040” ovality make sure its on spec with what ever grind you were up to.

2. Check the crank for any bending. I do this using a Dial gauge and a pair of V blocks. If you don’t have V blocks, you’ll probably get away with loading the main bearing shells into block and sitting the crank with some oil on them. Set your Dial gauge ove the centre main, zero it and slowly turn the crank. The Clock should stay on zero. Refer to the workshop manual to see what the acceptable amount of bend is (there is a tolerance on everything) and if there is a bend, make sure its within spec

3. Check your bearing shells thoroghly. Make sure there is no dags on them and that back and bearing faces are clean and smooth. Matt Read points out that there is a protective film on the bearing shell back, make sure this is cleaned off. Also, careful while handling the bearing shells that your hands are SPOTLESS. Any fine bits of metal or filing that maybe on your skin will easily impregnate itself in the soft White Metal bearing surface and will most likely score or damage the bearing journels in the crank. Matt was saying that he cleans his bearing faces by flushing them with clean oil, nothing else.

4. Have a look at the main shells (big ends are the same), you’ll see they have a tang. If you look at the cap and tunnel, you’ll see that there is also a seat for the tang. IT PUTS THE TANG IN THE TANG HOLE. The shells are a tight fit into the tunnels so don’t be too worried, and just be carefull that you don’t scrape some of the backing off when sliding it into the tunnel or the material scraped off will sit just on the edge of the shell and stop the cap mating properly. Do not put any oil on the back of the bearing shell (for obvious reasons, but I watched a mate of mine do it once). They go in their tunnels clean and dry.

5. With the shells in the block and in the caps, oil the bearing face’s like its going out of fashion, then place the crank in the block and give it a spin. Should spin so freely that when you flick your wrist it spins for half a sec longer under its own inertia. While your here, squirt a couple of drops of oil down the oil drillings in the crank.. why not

6. Drop the thrust bearings into the centre main, again there is one side with a tang, so think about where you are installing what.

7. Oil up the bearing in the caps and put them on. You should have dowells to locate the caps before you run the bolt into them. Don’t forget the thrust bearings for the center cap.... and as to what way around the caps go.. have a look at the tang in the shell, the tang should go on the same side as the tang in the shell in the block. Starting at main number 1, torque up one bolt and spin. It should still spin just as freely. The torque up the other bolt and spin again. It should still spin freelly. Continue this all the way to the 6th bolt on the third cap. If at any point it stops spining freely stop, disassemble and check your crank for journel size and straightness again. If its fine but still wont spin freely check you do infact have the right bearing shells. Where bearing clearance is concerned, the easiest way to measure it is using a product called plastigauge, flow the instructions in the packet and you’ll be able to measure the running clearance. I use it to log all my crank clearances.

*PLEASE NOTE, that the caps are matched to the block, its how they are machined, they are bolted on and bored... you can not use caps of another block without machining them to suit


8. Then after all the caps are tight, check bearing crush. To do this, I back off one of the bolts on each main, and slide a feeler gauge under the cap. Check the manual for correct bearing crush. You measure the crush amount with a feeler gauge.. so if its (for example) 0.004”, you’ll only get a 0.004” strip in there.


*TIP
When Matt finds that he has a tight bearing or they are picking up (and the crank is on spec, and the bearing shells are on spec as per bearing manufactures spec), he’ll strip the crank and bearings out of the block and using emery tape with kero, he’ll give the bearing craddle in the block and it bearing cap a bit of a sanding. He just wraps the tape around his thumb and gently rubs some material off. This is a way of avoiding having to send your block out for horizontal boring (line boring, tunnel boring whatever you like to call it).

If I can suggest however, if you don’t see any improvement after trying this a couple of times do not keep sanding the tunnel, it needs boring. And as Matt points out, its worth getting an A+ timing set, cover and engine plate after you’ve had your block and caps line bored, as it will alter your geometry and the A+ sets have a chain tensioner that will take up any slack.



9. Then check your end float. You can do this by pushing your crank all the way into the thrust washers and sliding a feeler gauge into the gap between the trust and trust face on the crank (the loose side).... or the way I do it, is stand the engine on end, using a dial gauge I take a measurement then slide the crank up (or down) into a trust face and take a reading off the dial gauge.

I know it sounds over the top, but I do it that way because the thrust seats in the block aren’t always square.. you’ll see that if you look at a worn thrust bearing. So you’ll get 30 different measurements with a feeler gauge and none of them will be a true endfloat.



On the topic of endfloat, most of us like to use a little extra endfloat. The workshop manual specifications say "0.002-0.003” " . Many of us believe that this is too tight. I use 0.008” in my engines, Matt Read was saying that he likes to run 0.005-0.006” on his upper thrusts (the ones that go in the block) and 0.010-0.015” for the bottom thrusts. GT mowog has run up to 0.010” on both thrusts in some of his engines but prefers to keep it between 0.005 and 0.008”. The Doc likes to run his at 0.007”......... But, if in doubt stick to what the Manufacturer says.


Just before I move on to ring/piston/rod assembly while still talking about fitting the crank..... a Machining defect that Matt has found sometimes, is having too much radius on the edges of the journels where they meet the webs. It is important that there is a radius here, if there was a sharp edge here instead of a radius, it would create a weak spot in the crank. Briefly, crank grinding is a cylindrical grinding process. Think of a toolpost grinder for a lathe only 10 times better and more accurate (It’s easy to lick less than 0.010mm or 0.0003937”). The grinding wheel needs to be dressed and shaped to an appropriate profile for the job you’re undertaking, so if you need a radius at the edges, you’d shape a radius into the edge of the wheel..... the problem is lazy machinists who don’t redress the wheel and you end up with so much radius that your shells won’t fit. Matt narrow’s his bearings when this happens... if it happened to me, I’d take the crank back and wrap it over the machinist's head.... I’m not at nice as Matt.



10. Clean up your pistons and rods.

11. Assemble pistons onto rods. Depending on what you have, the gudgeon pin might be held in with circlips or they might be pressed into the little end. Once assembled make sure you can rock the piston back and forth freely. It should literally go “clunk cluck” back and forth, if there is any resistance stop and work out why.

*TIP*
If your's are gudgeon pins are the press fit type, get your Machine Shop to fit the Piston to the rod. It's not an easy task for the inexperienced, it's very easy to crush your piston

12. Rings. Place each of your compression rings into a bore, and using a piston (turned upside down) I push them down square into the bore by about 20mm. Then using a feeler gauge I check the gap in the ring. Check the work shop manual for what the tolerance in ring gaping is to make sure its on spec

*TIP*
I like to by the next size ring up from the size of the piston I am using... so If its a 0.020" piston, I buy 0.040" rings. I do this so that I can file the gaps to the right size (or a size that I am after for whatever the application may be) please note, that I do this using a proper ring filer... you can do it by hand but I prefer not to. Most of the time when you buy pistons they come with rings for that piston, by all means use these rings if you like, so long as they aren't too small (ie, the gap is too big)

13. Once all gaps are checked I assemble the rings onto the pistons, starting with the oil control rings. Make sure all the gaps are offest. I try to avoid lining up the gaps with either the left or right side of the motor (front or back in a mini) so that the piston isn’t thrusting on them.. another habit I picked up working with GT mowog... When The Doc does his, He likes to line his up so that the gap in the top compression ring is at 180 degress to the exhaust valve, and then continuely offeset them all the way down to the last oil control ring.

14. I fit the piston in the bore ( before I compress the rings and slide them right in). Place each piston into its bore and measure the piston to bore clearance with a feeler gauge. Make sure its within the piston manufacturers spec as in the guys that made the piston. Different brands of piston expand at different rates and amounts so they will all have their own specifications. It is critical its within spec for warranty and also to make sure you don’t end up with stupid blow by or a seized motor.


At this point I wrap a bit of electrical tape around the Big end bolts so that they don’t damage the bore or the bearing journel. Matt Read has some tiny condoms he uses (I’m not game to ask ) and Morris1100 uses a bit of rubber tube.... Basically anything thats soft that will protect the bore and journel.

15. Put the piston in the ring compressor (and oil the inside of the compressor). Make sure you don’t spin the rings accidently while tightening it up. Get it firm in your hands, then slide the rod and piston down the bore till the compressor is touching the deck, then gently tap the edge of the compressor all the way around the edge to make sure it is sitting flat THEN tighten the compressor right up. Push the piston into the bore using the butt of a mallet handle. If it stops, don’t force it, you could snap the rings , so you’ll need to, just pull it out and start again. If you have a lot of trouble, after you tap down the compressor, just lift the whole lot out of the bore by a couple of mm and squirt a load of oil around the edge of the piston. Sometimes the chamfer at the top of the bore will catch the rings, so the oil helps “fill the gap”

**Note** The conrods in these engines are off set, if you look down the bore at the crank, you will see that the journel sits to one side. Make sure you put the right piston in the right bore. Also, make sure that the journel for the piston you are pushing in, is at BOTTOM DEAD CENTER. If it isn’t you may hit it and damage it during piston installation

16. Get one piston in at a time and put the cap on it with oil, exactly the same as with the mains, (as in how to put the shell in, and oiling and check bearing crush etc) You may also want to check your running clearance with plastigauge as you did with the mains.

17. Bolt on engine plate with gasket

18. Bolt oil pump on with gasket. Before fitting it’s worth filling the pump with oil and spinning it with your fingers so that its primed and ready to go. I normally only use normal oil because I know that most of the time, when I’m at this stage I’ll be fitting it into a car the next morning and starting it.... Matt points out that this isn’t going to be the case for everyone, so he uses STP instead. By pre priming the oil pump, it just means you’ll get oil pressure up sooner when you’re ready to kick the motor over.

*Tip*
Rodney found that the bolts that come with some of the oil pumps are the wrong length, be aware that if bolts are supplied, they may need changing... just check your pump and block to see what you need.

19. Insert cam followers with a slather of oil **NOTE** THIS ONLY APPLIES TO 1275 ENGINES WITHOUT SIDE COVERS. I WILL POINT OUT LATER ON WHEN YOU PUT FOLLOWERS INTO SIDE COVER STYLE MOTORS (Thanks Rodney )

20. Insert cam with oil on the journels... make sure it spins easily.... Cam end float is something that gets asked about at bit... Cam lobes (at least in these engines) are ground with a slight angle on them (as in the faces are not parralell to the core) and this spins the followers... due to the spining action, it thrusts the cam against the thrust plate on the engine plate,,, so while the engine is running, the cam will never thrust the other way... so don’t worry about cam endfloat...

21. If new cam followers are being used or a new cam (in which case get new followers anyway), get some “cam run in lube” on the lobes... if you can’t find any, I know people that have used CV grease for the same job and gotten away with it nooooo worries Matt Read likes to use a 50/50 mix of moly grease and STP for cam run in lube. Moly grease is Molybdenum Grease (CV grease is a molybdenum grease too).

A big thing with most steels is that after they are ground, they do not readily except oil, and with fresh followers and cams they need lube... but the splash from the crank doesn't cut it until they are run in... there are processes for making steels except oil after they're ground (like acid etching for one) but most new cams (or re grinds) won't have this... so having lube on there helps them out while they run in.

22. Bolt cam thrust plate to engine plate

23. Push timing sprockets onto the cam and crank (little one on crank, big one on cam)... push them all the way down. Now, push the cam back and forth into the thrust plate making sure its not stuck, it should still slide either way. Now push cam into thrust plate, put a straight edge across both sprokets and make sure that they are on the same plane... if there are any gaps under the straight edge, measure with feeler gauges and shim the low sprocket accordingly.

Matt Read will face his sprockets in a lathe instead of shimming because of problems he’s found with shims breaking down. I do too for some motors, I haven’t seen the problem that Matt mentions with shims breaking down, but the reason I do it is because it seems that you can only get sprocket shims in 0.005 increments...

But for the average Joe who doesn't have a lathe... shimming will most of the time be fine.... (No Matt!! Don't beat me!!)

24. Remove sprokets. Place chain over sprockets and line up the two dots on the sprokets.... GUYS I KNOW THIS ISN’T A GARENTEED 110 DEGRESS (As per timing for most std cams) but I’m not going into dialing up cams, that’s a 1500 word how to on its own ... for most std road applications lining up the dots is fine... and then push back onto crank and cam

25. Put timing chaing cover on with gasket... make sure the lower bolts down’t poke thru the engine plate far enough to stop the gear box going on...

*TIP*

A trick that Matt Read, GT mowog and myself all use... is inserting the crank seal in the cover, greasing it up, sliding the harmonic balancer into the cover... then... using it to centre the case around the crank while the bolts are loose... then tightening them up once its on centre. Otherwise you may end up installing the cover with the seal off to one side and wearing it out (or you may cop an oil leak is the other thing)




Head Prep


I don’t want to start a fight about whether or not you should lap valves.... so I’ll skip that part.... I do it, I think Matt does too... but I know it’s one of those “taboo” topics in some automotive circles so I’ll leave that one alone.

DO NOT UNDER ANY CIRCUMSTANCE PLACE HEAD ON ANY SURFACE EXCEPT MAYBE CARDBOARD OR A SOFT PILE OF RAGS WITH THE GASKET FACE FACING DOWN OR YOU WILL MOST LIKELY DAMAGE IT.

1. As was the case with the block, lightly deburr all holes, and touch up all threads with a tap. With the combustion chambers I run a file over the edge of them to get rid of any burr and ever so slightly round the edge off to remove any potential "Glow plugs" (I just mean hot spots that can cause pinging). Then oil stone the gasket face in a figure 8, even pressure and cover the whole face.

2. I wash it just like the block, every nook and crany, don’t forget threaded holes

3. Let it drain off. Then using a straight edge and feeler gauges, check it for flatness. I run the straight edge along the deck, down the center then try and poke a feeler gauge under it ANYWHERE... you're looking for as close to absolute flatness as possible and no more warpage than the allowable amount (again check manual). Repeat this procedure 5mm from either edge, then on a diagonal then the other diagonal

4. Get your valves and place into guides with a smear of oil over the stems. Flick them open and closed a few times to make sure they are free in the guides.

5. Place the valve stem seal over the valve stem and hard into the guide,, then place bottom retainer over valve guide, then spring(s), then top retainer.. Then using a valve spring compressor (or press) push the valve springs down and place the tappered locking keepers into the top of the top retainer and slowly release. They will lock themselves into the goove in the valve stem and the tapper in the top retainer


And that is your head assembled.



Putting The Head On The Block

1. Run head studs into the block with a bit of oil on the threads finger tight... some like to use loctite down here... I don’t personally, just my choice, I just do them up finger tight.

2. Have a final look at the deck and make sure its clean

3. Place WHAT EVER BLOODY HEAD GASKET MAKES YOU HAPPY over the studs correct way up etc I would suggest applying it dry, but there are sealers specially designed for head gaskets if you prefer.... JUST DON'T USE SILASTIC OR SOMETHING like one of my mates Dads was trying to do with his truck the other day

4. Drop the head on it.... not literally ..... "Place" the head on

5. Run your rocker post studs into the head

***NOTE*** if you are doing a side cover style motor, install the cam followers at this point with a slather of oil and then put the side covers on. The reason I don’t do it any sooner is so that while I’m turning the motor over in the engine stand, the followers don’t just fall out into the tappet chest.... very annoying when that happens

6. Drop push rods into their holes

7. Place rocker gear on head (after its pulled apart and washed)

8. Tighten up the rocker studs that are not also head studs

9. Start torquing down the head.... NOW.... ..... there are a million different opinions on how to do this... this is how I do it and my logic.. you do it how ever makes you happy ...... oil the threads.... run the nuts on and before they hit the head, squirt a bit of oil under them.... starting with the stud in the middle on the distributor side, torque it down to 10ft/Ibs... then the one on the back just left of center down to 10ft/Ibs... the one in the back row just right of center 10ft/Ibs.. now the one in the front row right of center... the one front row left of center... basically in a spiral patteren all the way out to the either end of the head. Once they’re all at 10ft/Ibs repeat the same pattern down to 20ft/Ibs... then 30ft/Ibs... then 35ft/Ibs then to whatever the specified torque is for the studs you’re using.... then back them off half a turn and do them back up to the final loading.

I picked this method up from a good friend of mine who is a Motorcylce Mechanic. I find it easier than trying to remember what number stud to do next

Whatever pattern you tighten it in, start from the centre and work outwards. And I personally wouldn't recommend reefing it down to full tension in one hit.


10. Set tappet clearance, and put rocker cover on with new gasket (don't be tempted to over tighten or it will leak)



Home Straight



1. bolt on your water pump,,

2. Bolt on Gearbox with new gaskets and half moon seal

3. turn engine on end with transfer housing end facing up. Instal idler gear (check for endfloat using feeler gauges, make sure its on spec) place the primary gear thrust washer on the tail of the crank (camfered side in) with the primary gear and retaining clips and check endfloat in thrust washer... then remove clips and primary gear, load primary gear into a new seal in the transfer housing... Then apply new transfer housing gasket .... place transfer housing and primary gear over the studs making sure primary gear doesn't fall through the seal, then bolt transfer housing down.

14. Place clutch backing plate over crank tail, then NEW friction plate, then flywheel with the straps attached (get your flywheel machined if need be... as 850man mentioned) then bolt straps to clutch backing plate. Then place the flywheel retaining washer/key in the end of the crank (the right way around, the tabs are off set) then bolt it all in.

15. bolt clutch cover on with the arm in place

16. bolt harmonic balancer on






A Few Handy Tips For The Road

These are a few handy tips that some of the guys dropped along the way... I won’t give you anymore of mine, I think I’ve given away enough of my witch magic for one sitting I kid, I kid...

Rodney says don’t rush. And he’s not wrong. Take your time. If you skip anything of make any mistakes along the way because you rushed you’ll be most displeased with yourself. Take it slow and triple check everything. He also points out something that I totally over looked and forgot to mention... make sure you are clean, make sure if you’re a long haired hippy like me, that your hair is in a net or under a cap or something, make sure that your tools are clean, and of course make sure your work area is clean.... CAN’T STRESS CLEAN ENOUGH

AEG163job, points out too that you should really make sure no one interrupts you and that you’re not distracted. You need full consintration to make sure you’re doing the best job you can.

Matt points out a very important fact here too.... DO NOT TRUST MACHINE SHOPS. Check everything yourself. If you find their mistake before you assemble, it’s their problem... if you check later it’s your problem... the amount of people who over look this and end up red faced is worrying.

A tip leant to us by Kevin (drmini) is that if you are using ARP rod bolts, buy Ford FE ones instead of mini one because they are cheaper, though it does require a bit of machining to get them to fit correctly

An idea that David Rosenthal throws up, is that on motors that he knows he want be starting for a few days or weeks, he smears a bit of copper grease on the face of every moving part/face... I haven’t tried this, it’s the first time I’ve heard it... But if I was going to have blind faith in the word of anyone on this forum where mechanical engineering is concerned, it would be David, so I’m happy to believe that he has had success with this



Another thing that Matt and David both point out, is that so do make sure that everything moves freely and is within spec.






Other How To Links

These are some useful how to links that others have put together that may help with other parts of your rebuild or further modification.

The first one I’ll put up is an important one, and one you’ll need to finish your assembly.. its Gafmo’s how to on setting tappet clearance. Obviously much easier in the engine stand, because you can turn the motor over by hand
http://www.ausmini.com/forums/viewtopic.php?t=10528


This is the Doc’s how to on doing a ball valve conversion for your oil relief, I would suggest this conversion for sure when you’re up to it...

http://www.ausmini.com/forums/viewtopic.php?t=58088

If ever you get up to a stage of more serious engine modification, this is a link to Graham In Aus’s how to on cc’ing cylinder heads. It’s a pretty good method he shows and very similar to the way I do it.

http://www.ausmini.com/forums/viewtopic.php?t=53856

This is Doogie’s guide to removing the engine (hey you gotta get it out first )

http://www.ausmini.com/forums/viewtopic.php?t=45377

This is the Doc’s guide to making a flywheel puller.... if you can weld, this will save you some cash during disassembly...

http://www.ausmini.com/forums/viewtopic.php?t=12888

Just a few things I would add to that epic voyage....

Micrometers. Get 3 if the cash will stretch;-
0 - 1"
1"- 2"
2"- 3"
If your really tight for cash though, a 1"- 2" will get you out of gaol, but only just.
These engines are imperial, so buy imperial, don't try to convert from metric.

Torque Wrench - 1/2" Drive with a range from 25 to 150 ft/lbs. If you've the extra $$$ get a 3/8" Drive with a range from 8 to 50 ft/lbs.

I wouldn't consider Plastigauge Optional - it's mandatory.

I would check the Cam Bearings at the stage of the first clean, usually not actually try the cam a this point, but ensure the oil holes line up. At the point of final clean, I'd actually be checking with the cam at a very early stage.

Also, after the first clean, use the old main bearing shells (cleaned of course) to check the oil holes line up. Often they do not. They are more difficult to correct than first meets the eye, but not at all hard. Probably best way is to file them. Don't drill them unless you have a mill or the like and take extreme care not to damage the bearing tunnel in the block.

Rod Bolts & Nuts (if your engine uses Nuts). Don't even think of re-using the old ones. Inspect them as they will tell a 'story' but don't reuse them. Bolts are cheap, especially when compared to the consequences of failure. For most applications including mild tuned engines), factory parts are just fine (just make sure they are in a sealed Austin Rover bag ) Although on the small bore stuff, I use Unbrako brand cap head bolts, these are better and cheaper.

Get a good Workshop Manual to suit the particular Block & Head that you are working on (NOTE: The Leyland Black Book does NOT cover the A+), however keep in mind that these are usually written for Qualified and Experience Motor Mechanics, so while it might say, the end float is 0.002 to 0.003", it won't say how to check it, but at least you have all that kind of info.

Pistons & Rings. I think PK has mentioned it, however, I'll just throw it in that the Piston Manufacturer's advice should be followed regarding these, not the factory info.

Be sure to have your radiator cleaned and tested (maybe re-cored?). What about your heater? Does it have half the Dead Sea in it? Don't skimp on a water pump, put a new one on.

How's the distributor bushes and the springs for the advance mechanism? Have them checked and overhauled as needed. It can damage your new engine.

Check ALL and EVERY new part. A disappointing number come out of the box that are less than satisfactory in quality and / or finish.

Be sure to oil all fastener threads before torquing. Google it. There is more to torquing up fasteners than just throw the torque wrench on the fastener and reefing on the handle.

It has been mentioned, however, I'll say it too. If you start your engine build project on Friday Night and say 'I'll have it finished by Sunday' then save yourself some heartache and don't even start the job. It takes and long as it takes. Be prepared to stop for a few days at some point(s) during the build to have items sorted.

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This is an amazingly useful topic!
Thank you all!

One point mentioned by Matt Read in the initial topic was to check for drag/grab marks on the crank/rod bearings ,

if that's the case how can we rectify this ? Does it means mains/big end bores need to be checked and line bored by a machine shop ? or there is something we can do ourselves ?


Cheers
Luis

yes very very often the case & even more often left untouched by the average Joe/Jane Doe,,, but i whip it all apart & emery the caps/tunnels & then clean it all again & re-fit new bearing shells,,, yes i use a lot of bearings & i just fit the marked-up ones into cheapo 2nd hand engine re-builds

"Usually" it`s just a matter of emery-ing the bearing cradles ...wrap some emery tape (soaked in mix of oil & kero) & gently rub (Your Thumb is good) where the bearings sit --> 'Normally" the problem is mainly on the sides, at the seam or join of the cap to rod , or cap to block,, if in doubt have the rod/block checked with micrometer & machine to suit,,, you can have the rods "Re-sized" (if new bolts are used then this process is mandatory) & you can also have your block "Tunnel-bored",,, now as much as i hate doing this, "some-times" you just have to & then maybe an A+ type tentioned timing gear set would be worth fitting (with the cam timing set properly with either vernier gears or off-set key) as the crank is now slightly higher sitting in the b lock so the cam chain/belt will now be that tiny bit slacker,,, so will the mesh between the primary & idler gears,,, don`t be worried , it`s "Usually" barely a bees-dick

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Thanks a lot Matt , will be aware and check this for sure.

cheers
Luis

Rebuild the gearbox as well. Theres no use bolting a buggered gearbox onto a good engine. You can never get an assembled gearbox properly clean so take the time to pull it apart and clean it properly, replace any worn out parts, bearings etc, check balk ring clearence, idler gear, primary gear etc. Fit a new clutch plate/diaphragm/thrust bearing & have the flywheel/backplate machined if required.

Theres nothing worse than a mini with a buggered gearbox & a shuddering clutch, combined with a new engine will no doubt result in a early demise of your engine.

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Have a Nice Day.
If already having a nice day please disregard.

Oh & Phat,,, i use 5-6 thou on crank end float,,, on the upper thrusts

however--> on the lower thrusts i set them to 10-or-15 thou

sorry i might not have made it that clear before

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Well done Kat, a really useful information source for all of us.

We owe you a beer (maybe even a case!)

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1967 Cooper S - new front bearings to do.
1965 Cooper S shell - all painted up, ready for fit out.
1969 Cooper S Mk2 - claimed by 2nd. born
1966 Deluxe- next rustoration!
Mk 2 & XJ6 Jags. Less said the better.

The books might say .003" end float is fine on a 1275 crank, but if it's going to rev it is nowhere near enough.
These cranks flex at high rpm, too little endfloat will result in spalling of the bronze thrust washers and overheating of the centre main, probably followed by a spun bearing. I have the evidence..
Now .007" works for me.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Very true

At the very least I pull down my gear boxes and scrub them up before fitting... At the very least.

I know not every body does it... but I too would strongly recommend it....

Just my way of looking at it... and it might sound dramatic, but you wouldn't pour old oil into a new motor and then throw a fist fulll of swarf in there.... The gearbox is part of the motor on these engines so clean it out just like you would everyother part of the motor.





Now you're starting to let some more of that missing 90% slip


Cam bearings, I agree... check them as soon as you can. I should have put that in the clean up, I forgot to mention them in the original draft how to (can't think of everything when I'm not sitting in front of a motor ) so I just squeezed it in after matt reminded me. I'll fix that.

I'll also include mic sizes, good point.

Rod fastners, very true, don't want your caps detaching at 6000rpm because you were stingdy... they're cheap.... a hell of a lot cheaper than a new motor.

The bit on servicing the dizzy, I'll squeeze that in too.

Also the part on the heater matrix and radiator.... just like your gearbox is a part of your oil system, your radiator and heater are part of your cooling..... on this topic I might also mention oil coolers... if your motor has one, they are near impossible to clean, so I just replace them on rebuild....

Pretty sure I covered all the other points you mentioned too

Thanks for your input





All gold.... all going in as advice





My bad, I should have asked you what you meant.




Thanks Kev, I'll include your findings as well. A lot of people on here are often intrested to "hear what the doc has to say," so thanks.




If you guys all want to keep adding stuff thats fine, go for it.... I'll put it all in tonight.... hopefully at a more sane hour than 2:30am

And this should be a 'Sticky'

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

hee hee,,, Now i really don`t have the longest post title

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

haha, tell me about it. I wrote this in Word before I posted it..... you want to know how many words it was and how many pages? ..... ....... I'll tell you anyway ...... 5,624 words and 14 pages....... By the time I re-do it again tonight with everyones helpful words of wisdom, it will probably stretch out to 20 pages I'm guess ....... what were you saying yesterday about writing a book?

PK , I assume that putting in all the pipe work and fitting the radiator is a separate thread
.

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