Inliners International Forums General Discussion Engines 292 Crank end play = flywheel wobble?

Hi guys-

Found a rather odd issue with my 292. However, let me discuss the motor itself really quick. It was purchased as a "fleet rebuild" and a leftover from a contract which ended early; I picked it up off Craigslist for a song. It has stock internals, but I'm running an HEI, Offy manifold, 500CFM Edelbrock carb, and Langdon cast headers. It's got a remachined and balanced 158-tooth flywheel off the 230 that was originally in the car, along with a 3-speed Saginaw manual trans. The car is a 63 Biscayne, and this engine has been in the car for ~10K miles, which were trouble free until this summer. On to the issue at hand:
The flywheel came loose this summer, despite using 6 1/2" retaining bolts and a dowel pin! During the diagnosis, we discovered that the crank endplay is at .015" - way beyond factory spec. We thought not much more of it, put things back together, and drove it. The same thing happened less than 1000 miles later! We then used Loctite bearing adhesive all around the crank flange, the dowel, and the bolts to prevent loosening. I have driven only a few hundred miles since then, and things "seem" OK...but the car is put away for the winter so I can't test further until Spring.

I'm wondering, specifically, if:

- the crank endplay might be creating a vibration bad enough that things are just loosening up over time?
- there is a crankshaft thrust bearing or washer on this motor, and if so, where?

I'd appreciate any help or other thoughts you guys might have. Many thanks in advance!

How much do you rev the engine?
Did you balance the flywheel, pressure plate?

Another Question Are useing the Star washers Under the bolts?
If so Trash Can them. They are not helpping your issue in anyway.IF anything they also helping the issue.
Xs2 with Tom's question.

Another question what dampener do you have on it? New Used Or other wise?

Max RPM the motor ever sees is 4500; it might be worth stating that at freeway speed ~70MPH, RPM sits right at 3000.

Pressure plate and flywheel were both balanced prior to install.

No star washers in use.

Dampener is a used stock unit. Maybe it's giving up?

Shaking the bolts loose in a 292 is really pretty common. Its a harmonic problem relative to its design. I would be concerned about the excessive thrust movement, but don't think its contributing to your problem. If caught early enough, it might not require the crank to be removed to fix the thrust surface on the crank, left unattended, it can manifest into a larger problem.

Are you a 100% sure it was/or is installed the same as it was balanced? And not a bolt hole off from the set-up the balance was done at.

It could also be not surfaced square I.E. thicker on one side than the other hence the wobble. this is very rare but with todays inexperienced and who will work the cheapest it will become more and more. you can find the run out very easy with a dial indicator also you can get crank thrust spec's.

From what I have seen don't run an inline at 3000 RPM constant, the problem is harmonics, when I drove my car on the street you could not see out the rear view mirror at 3000, it would vibrate so bad, above and below was fine.

If you keep the flywheel on the next thing to come off is the pin in the flywheel then the harmonic balancer in that order. Besure that the bolt is in the balancer.

I use a strap as a lock to hold the flywheel bolts and the pin from moving, Two bolts go through the tab and hold the pins the ears on the end of the tab bend over the flats of the bolts.

Harry

The lock tabs were standard GM in the early years. Are they not used on later inline 6's?

I have found Stage8 flywheel bolts work well for keeping the flywheel on. They sell the 1/2" set for Hemis and other big block Mopars.

STOCK GM BOLTS DO FINE ON FLYWHEELS IN ALL BUT RACE APPLICATIONS