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Engine Rebuild no oil pressure
https://ausmini.com/forums/viewtopic.php?f=2&t=100055		 Page 1 of 2
Author:  Ramon Maurice [ Mon Jun 01, 2020 1:47 pm ]
Post subject:  Engine Rebuild no oil pressure
Afternoon,

Please excuse the non technical terms as I'm not a mechanic.

I a have an A series 1275 motor which was rebuilt by Wilkins Performance Engines (Sydney) in 1993 to +060. with a Kent 288SP cam with spider drive oil pump. The motor sat in the car without being turned over for 25 years an unfinished project. I took on the car in 2019.

The motor was pulled out and disassembled. motor set to a engine performance centre. A rebore, new pistons, rings, bearings, lifters were installed. The original cam was kept due to the spider drive and a plate (spacer) that seemed to be homemade between the oil pump and the motor.

Now i have the motor back in the car and at start up stage. No oil pressure coming up on turning it over with the starter only. I primed the oil pump prior to turning over through the front of the motor I've checked the bottom end of the motor and there is no blockage.

My questions are as follows;

1. With the cam being 25+ years old could it have been a cam from another model and adapted to fit using the home made spacer, or is this normal ? I may be losing pressure through the spacer.

2. It may be possible that in the 25 years something has gotten up in the oil gallery and created a blockage ie: mud wasp etc. Can an engine shop flush these out ?

Are there any other common steps that I may have overlooked as a notice in relation to motor preparation for oil pressure.

I'm reading oil pressure from an aftermarket Smith gauge so should be accurate.

Any thoughts would be appreciated before I pull the motor and dismantle for a second time.

Cheers
Author:  drmini in aust [ Mon Jun 01, 2020 2:28 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
That's a 1275 automatic block. There is no oilway for the pump outlet.
It has to be drilled through from the relief valve hole after removing the relief valve seat.
See my blog in the how to forum. With pics.
Bottom of p5.

Edit
You will have to strip block to do this. Including the main oilway plugs.

Edit 2
Pull spacer out and check, but I doubt block is drilled and the spacer not.
Author:  winabbey [ Mon Jun 01, 2020 3:09 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
This is the How To mentioned above - viewtopic.php?f=25&t=90470
Author:  Ramon Maurice [ Mon Jun 01, 2020 3:25 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
Thanks Dr Mini / winabbey,

The block is stamped 12YEAH4355 Would this confirm it is a 1275 Auto Block ?
Author:  drmini in aust [ Mon Jun 01, 2020 3:30 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
Yes it is a Morris 1300 auto block, 1275cc.
Like mine...
Author:  Ramon Maurice [ Mon Jun 01, 2020 3:45 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
Great, I think.

Looks like this is a job for the engine shop.
On the up side I'm becoming efficient at pulling the motor !
Author:  Ramon Maurice [ Sat Jun 06, 2020 2:18 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
I think I found the issue. Block had been drilled through, but when I pulled the cotton reel out I had the two holes which I assume would not allow for oil pressure to build.
Author:  drmini in aust [ Sat Jun 06, 2020 3:16 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
I was wrong.
Looking at that pic again which isn't right way up, yes the outlet is drilled but the inlet is blocked with silastic?
That's where the oil comes up from the sump.
Why is it blocked??
Edit:
If that's just a temporary plug put there to keep dirt out, I suspect you may have a leak behind the plate.
As I said in my blog it must be a tight fit and have a trimmed gasket behind it.
And, the plate must have a chamfer on its corner to clear the radius in the block recess. If not the inner gasket will leak.
Use Loctite 515 all around the recess corner before fitting the plate.

Re the cotton reel, if the 2 holes aren't brazed up you will still get oil pressure but it will bypass the oil filter.
You can still buy the manual valve seat which hasn't got the holes.
Edit:
I've built 3 motors using these modified auto blocks.
Author:  TK [ Sun Jun 07, 2020 11:41 am ]
Post subject:  Re: Engine Rebuild no oil pressure
I agree Kev, leak behind the oil pump adaptor plate.
Author:  Ramon Maurice [ Sun Jun 07, 2020 12:38 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
Thanks gents,

I've replaced the cotton reel with a manual one (no holes)

cleaned the oil pump plate and sealed it well. Motor going back in Monday/Tuesday will let you know the outcome.
Author:  Neilwillo [ Sun Jun 07, 2020 12:53 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
Have you thought about running it on the bench before you go to all the effort of reinstalling. It’s all self contained with the radiator so its not hard to get it running.
Neil
Author:  TK [ Sun Jun 07, 2020 5:06 pm ]
Post subject:  Re: Engine Rebuild no oil pressure
Ramon, my adapter plate was secured to the block by a screw. Does yours have this? It is vital not to leave this out.
Author:  Bill B [ Mon Jun 08, 2020 10:30 am ]
Post subject:  Re: Engine Rebuild no oil pressure
TK wrote:
Ramon, my adapter plate was secured to the block by a screw. Does yours have this? It is vital not to leave this out.


Can TK explain why it is vital the adaptor plate has to be screwed to the block?
I have an auto block modified as per Drmini's "How To" but have never assembled or run it. Wouldn't the gasket and compound be enough to seal the plate to the block?
And if the screw is necessary, does it have to be either countersunk or counterbored to leave a flat surface for the pump to mount to?
Author:  TK [ Mon Jun 08, 2020 10:41 am ]
Post subject:  Re: Engine Rebuild no oil pressure
Bill B, Fred Sayers did my auto to manual conversion. There was a screw that held the plate. I thought that I knew better and left it out. The result was very little oil pressure. Ripped the engine out put the screw back in and got great oil pressure.

I can't remember but I'm sure that it was countersunk.
Author:  Bill B [ Mon Jun 08, 2020 10:48 am ]
Post subject:  Re: Engine Rebuild no oil pressure
Thanks TK. Interesting....
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