Out of balance pressure plate???????

Can that happen? Would that cause a big vibration? Am wondering if that is my issue that I am trying to get rid of. Has anyone encountered that problem?

 

If you have a 50oz balance crank(post '81) and the earlier 28 oz flex/flywheel it's going to vibrate... Same deal if you have the 28oz crank(pre '81) and a late flywheel...

 

did the vibration start all of a sudden?

 

The engine/trans combo was traded for and was not rebuilt. I was told it ran fine, and upon removing the valve covers and intake, found the insides to be extremely clean, so it was resealed and put back together then installed in my maverick. The vibration has been present since the day I started the motor. All accessories have been eliminated by way of removing the serp belt, changing harmonic balancers and flywheels, and running the motor without the trans. All the motor mounts are new. The motor runs strong and does not miss and is timed correctly. So before I pull the motor for rebuild, I thought just maybe, the only thing I have not changed out....the pressure plate and disc.....might be the cause for the vibration and if I changed those items out that might save me a big dollar amount. SOOO, this week I plan on removing the trans one more time and removing the clutch stuff, but leave the flywheel on then run the motor. If it still vibrates, then it will get torn down, but if that vibration goes away, well then I will get a different disc/plate.

 

Best of luck with that. I hope it's something simple.

 

I have seen one pressure plate out of balance, they are balanced different ways by each manufacturer..... In the link below you will see the big silver washers on the Hays pressure plate, that is how they balance there's.....

The Centerforce in the pic below has round weights attached in the outer bolt circle area..... Also the weight ring in the center usually makes noise and I have seen it shift on the fingers and cause out of balance issues that come and go(we determined that after the weight ring was cut off and the issue went away).....

Odds are that's not it, it is very rare..... I would bet on something being out of balance with the motor and or flywheel/balancer combo.....


http://www.jegs.com/i/Hays/490/85-1...5&cadevice=c&gclid=COWrtcLj68UCFUERHwodoUQAPA

 

Instead of full speed ahead, damn the torpedos, take a little time to find out what you have... My guess is if you get the correct flywheel & harmonic balancer it will be fine...

28oz balance cranks have 2M or 2MA stamped into front counterweight

50oz balance are marked 2MAE



Also it's easy to find when the block was cast(no this doesn't help if someone swapped cranks)...

2E11 on my original Comet block is May 11, 1972, the D2OE-6015-AB engineering number places it as 1972.... Note the casting date repeats every decade, IF engineering number had been E2xxxxx, it would have been a 1982 block(and a 50oz vs 28 of 1972)... F2xxx, 1992 which would be a roller block...

BTW if engine is a factory roller block, it's probably 50oz as 28oz had been discontinued four years prior to the rollers...

 

Yes it is a roller engine from a 89 mustang, so the Hb and flywheel are also 50oz

 

Well if that's the case you'll need to verify what crank is installed... If it's rebuilt, probably has been swapped or has wrong weight pistons...

Did you notice if crank has been cut or welded?? Possibly has a botched balance job?

 

Am pretty sure this motor has never been apart before me getting it, it had probably a half inch of filth, oil and such, all over it. I took it down as far as I could without taking the heads off it and it looked all original, however, I didnt check the piston skirts or the crank #, so cant be certain there.

 

Assuming it's never been apart, I'd say chances it won't balance with correct balancer & flywheel are slim to all but none...

 

do you know any history of the motor, as for why they were selling it and what condition the car/truck was in that it came from?

 

I chased a vibration/shutter in my Duster back in the 70's that I was never able to find - it only occurred while releasing the clutch then would go away - had flywheel cut - changed the rear main seal & thrust bearing in the engine because of some oil getting on the flywheel - replaced the clutch & pressure plate, rebuilt the clutch z bar - nothing would get rid of it so I know your frustrations - could be the main shaft or bearings in the trans - spins even while in neutral

 

so nobody thinks it could be the pressure plate? I ran it without the trans, so am certain it isnt in the transmission, whats the odds of having 2 flywheels with a problem? Both were 50oz. And 2 different HB's that didnt solve the problem.