The funniest damper failure that I have seen was at Bathurst when the car in front of me had the outer ring fall off and it broke his back wheel on the way out!

And I bet you saw the shrapnel coming at you and thought SH******T.

I had a very scary one on a big ruston engine. They have the "damper" as part of the flywheel on the rear of the engine. The engine developed a bad vibration and I thought something had gone thru the prop. So reduced revs and plodded on. The vibration got worse so I decided to shut it down and run on the other eng. As the eng came to a stop I was turning on the aux. g/box lube pump and heard a very loud bang. The outer ring [that weighed about 1 ton just fell off and rattled around the intermediate prop shaft. What a mess!!! but I looked at the bright side at least it did not happen at full revs.
I have seen one come off a clatterpillar genset and ricochet around the engine room.

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Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

used Romac twice, no failures and both were perfectly balanced from factory and needed no drilling.

mini7boy,,, the whole first page shows that one person had "Heard" about failures,,, that`s all

the 2nd page consists of you basically telling David R that he is wrong with one of his reasons for balancer failure ,,, you then continue on attempting to teach people the hows & whys dampeners should be fitted to all engines , carrying on as if David has no idea,,, & thern begin to disagree with me , when all i was saying was that david was just simply describing "One" of the possible reasons for failure of said component.... no one else to show any proof of Romac balancer failures on this page either.

The 3rd page is much the same, srtill no proof of balancer failure on it`s own merit.

The 4th page has a lot of "other" related info pertaining to the original topic, Included is a few ver valid questions from other people who are genuinly interested in hearing more,,,, added to the sarcasm thrown in from various people. again, no balancer failure on it`s own merit, seems to me there`s a seperate underlying cause to the balncer failures other than just simply the balncer failing (apart from dirty grotty old std issue balancers failing from old age & oil contamination of course)

all good so far & quite a fair bit of quality information has now been shared

the 5th page has some more events & related stories of balancer failures,,, so far it`s all been pretty well on topic & mostly answered your original question, & yet still no hard eveidence that Romac Balncers just fail on their own accord

i`m pretty sure you have your answer now yeah?

I have another one for you,,, Toyota surf, 4x4, runs for years without problem,,, suddenly it`s got this awful wobble building within engine speed,,, the harmonic balancer is found to be breaking up,,, cops a flogging & needs replacement,,, (at this point i`m suspicious because from my previous experiences, i believe there is usually another problem which has caused this) ,,., but all the people involved have mentioned that we can only fix what we know & see is wrong first , & then carry on,,, so we all agree & life goes on right? well the whole engine is still funny "feeling",,, (sorry no text books or torsional vibration web sites here) something just isn`t right still

well a week or 2 later & the flywheel/clutch assy (a 2 piece "swinging" flywheel assy thing),,, is discovered is faulty,,,, you`d probably need to talk with toyota Surf specialists to gain more info on it`s design if you were interested in finding out more on that topic,,, but it just goes to show the same thing occurs in other cars & not just mini related

HHHmmmm was it the flywheel & clutch assy that caused the balancer failure ???
or the balancer that caused the flywheel/clutch assy failure???

mini7boy,,, you asked,,, i believe you have been answered,,, & not one person has reported a Romac balancer failure , on it`s own accord, based on """fact""",,,

only one person has suggested that he`s "HEARD" of failures, but given no "FACTS" as to why or even "IF" i was purely a balancer failure & not caused by another issue.

if you`re done with it , then good.

Scott (Ballistic) is just as childish as almost everyone around here, (from time to time)sorry if you`re too mature to notice the fun part of this forum

you have been answered with very serious & solid quality information by some very experienced people, yet you chose to (& i quote) --> "Disagree"

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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 said Matt, have you been taking elocution lessons?

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Simon

The adventures of an owner builder in the Tallarook Ranges

Vibrations can do funny things. They can travel along a shaft and cause a problem on the opposite end to where you think the problem is.
A harmonic balancer can cop a flogging from a flywheel problem.
A cam follower can break due to a timing gear problem.
A cam can break from a crank vibration.

I had a truck that went through a period where it kept breaking a hydraulic brake pipe on a rear axle. The problem was on the front tailshaft (it was the three section shaft) the vibration ran right along a tailshaft and into the axle housing.

So back to the initial problem of an engine with a broken crank and a balancer with signs of distress.
Did the balancer break the crank?
Did the crank break the balancer?
Did the clutch cause both of them to fail?
Something else?

The answer is I don't know because I don't have the bits to examine.

OK mini7boy, The "terminology" of a componet is not the issue here. The job it does is what is under dissusion.

You asked a question about a romac balancer failure. I think that has been answered. No one here knows of a failure of a romac "item"

We have been trying to help with other "ideas" that could cause such a failure, other than a manufacturer's faulty product.

You have also stated that you have run this topic past more knowlegable engineers /people than all those on this forum. Now tell me what have they said that could be the cause of the "componet" failure. I am interested in what conclusions they have come up with.

From my own perspective, a degree in marine engineering and 40+ years working on many types of engines I must not understand the principles of engine design.

_________________
Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

David you are to polite
Love you work

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http://www.youtube.com/watch?v=nDMkVq1jRGU

I have cleaned this thread up and unlocked it at the request of those who actually do want to discuss this topic reasonably and to the benefit of members.

To BOTH old & newer members, I would like to say this -


I see the knowledge and value in this thread continuing and would like to see it remain open so follow the rules and forget the egos.

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Good Thread - Its amazing what I have had to unlearn since being exposed to minis/mokes.

"99 percent of cars' doesnt seem to apply to these little beasties.

The reason they are called Harmonic Balancers is because the vibrations in the engine cause high pitched "noises" and these "noises" can cause fractures in the metal components in the engine especially the crankshaft as it absorbs most of the "vibrations/noises".
Now we already know there is a rather large "noise, vibration" recipient at the back of the engine (clutch end) being the flywheel but at the other end there is the need for a pulley assembly from the crankshaft to drive the water pump, alternator/generator and the only way to stop the "noise" from causing damage (eg: crankshaft to fracture and make a hell of a mess inside an engine) to the crankshaft at the pulley end of the engine is to fit a specific metal mass to absorb, equalize or dissipate the "vibrations/noises".
The "noises" are as we know sound and if there are many sounds at different levels/frequencies (eg: at a concert, opera, etc) and they are not synchronized or in tune they can hurt while listening to them but when they are in synch or at the same frequency they sound great and "Harmonious" or in "Harmony".
So to conclude yes the small round lump of metal attached to the cranksahft pulley end of an engine (not all engines) has a "vibration damper" but it is also a "Harmonic balancer" as it is absorbing etc the various pitched "noises" created in an engine and turning them into the same "noise/sound/frequency" to cause less damage or metal fatigue in the engine, especially in the crankshaft as it is the receiver of most of the "noise/sound/vibration". So between the Flywheel and the Harmonic Damper the "noises/sounds/vibrations" are relativly equalized.
Yes it does the same job but it has 2 different names, Harmonic balancer and Vibration damper.

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http://www.youtube.com/watch?v=nDMkVq1jRGU

This is just another case of if enough people call something by an incorrect name, that name falls into common usage even though it is completely incorrect in describing the function of the component.

the technical paper listed below is available on the website of BHJ Dynamics, a firm that manufactures a variety of crankshaft torsional dampers including one for A-series engines.
Their website is at: http://www.bhjdynamics.com/

the following text excerpt is taken from this technical paper on crankshaft vibration dampers:
http://www.bhjdynamics.com/downloads/pdf/tech/BHJDynamics_Damper_Info.pdf

""
Balance – The damper is no more of a “balancer” than an ordinary belt pulley would be.
Nothing about the resonant motion of the inertia ring /rubber construction does anything for balance. The damper is balanced to a neutral specification for internally balanced cranks and may incorporate a bobweight for externally balanced cranks. BUT, the balance is a completely separate function from the torsion control.
""

mate, it doesnt really matter what it's called, they all relate to the exact same object, that's what it's commonly known as. You might not agree with that fact but thats just the way it is, it's not the only part that's known by 2 or more different names. I personally don't know that much about "harmonic balancers", or "torsional dampners" and i've been looking at this thread with great interest, learning a sh!tload because i'm doing my first engine rebuild at the moment, but it's just one of those things, no matter how much you campaign or feel strongly about, its just not going to change, ya know?

just my $0.02

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'73 clubby s "cryo" - sold
Operation Evil Sesame Street!

These are the people you need to contact with your questions as it is thier product you are questioning.
http://www.romac.com.au/
http://www.romac.com.au/balancers.html
Phone 61+8 8261 7222

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http://www.youtube.com/watch?v=nDMkVq1jRGU

I think we have now got the picture - the round thing on the front of the engine that drives the fan belt plays an important role. It should be checked whenever there is any major engine work done - if old it probably will show signs of deterioration and should be refurbished or replaced. If 'newish' and it fails 'prematurely' then it may not necessary be a manufacture fault in the thing itself and we should look further for other causes along the crank shaft to as far as the flywheel and clutch.

Information noted and stored.

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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!