'86 302 Balance question

Nov 14, 2004 4 Replies

I realize this FSB balance issues have been asked and answered here before but I have an additional couple questions.



I recently bought a vehicle which has a '86 5.0L Mustang engine which vibrated when it ran. I noticed the ring on the harmonic damper was cocked and thinking that was the problem, I bought a new 50 oz. damper to replace it with. When I pulled the bad damper off, I noticed it was a 28 oz model - no wonder the engine vibrated!



In checking with the guy who put together this engine he admitted to putting on a 1965 damper - a '65 flywheel too! I checked the flywheel he put on and its an old 160-tooth model. (slap - slap!)



Now for my question - I now have a good damper on the engine now but as for the flywheel, should it be a neutral balance or a 50 oz. imbalance? The engine runs pretty vibration free now, so I'm guessing that I need a neutral balance 'wheel. Is that correct? Does the '65



160-tooth flywheel have neutral balance? Do I need to get that old flywheel off of there or should it be OK?

Thanks!


Depends on what year the engine (crankshaft) is. The '65 flywheel is a 28oz imbalance so it too would need to be changed, that is, if it's actually a later model engine. I would be suspicious because a 28oz flywheel on a 50 oz crank would still vibrate like hell. As far as I know there is no "neutral balance" flywheel/flex plate from the factory. It's either 28oz or 50oz imbalance unless you're running a custom crank. Be sure you figure out what you're engine is because an out of balance condition would ruin the engine very quickly. I wouldn't drive it until everything got worked out.

Mark

Going on the assumption that its an '86 302 with a 50 oz imbalance, it now has a 50 oz. imbalanced damper. So is the engine now balanced or does it also need a 50 oz. imbalanced flywheel for a total of 100 oz. of external balance? Does just the damper need the 50 oz. imbalance weight or does the flywheel need one too?

Thanks, Dave

Get the 50oz flywheel or flexpate (A/T). You must have this. No other balance will work.

DC

Early engine use a 28oz imbalance damper and flywheel. later use a 50oz imbalance damper and flywheel. There's no mixing and matching.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required