flywheel pressure plate question
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flywheel pressure plate question
Did what I think is a ignorant/dumb thing. I mixed up some 2 liter flywheels and pressure plates. Am I right that they are "waited/balanced" with each other so they cancel each other out so they are balanced with each other. Did I get this right?
Do I need to take a flywheel and pressure plate to a machinist for some kind of balancing? I know that I should mark them when I take them off the crank but this was so long ago and before I "knew" better. How much does this matter?
Thanks
Joseph
Do I need to take a flywheel and pressure plate to a machinist for some kind of balancing? I know that I should mark them when I take them off the crank but this was so long ago and before I "knew" better. How much does this matter?
Thanks
Joseph
- fasty67
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Re: flywheel pressure plate question
These can be balanced as a complete rotating mass with everything from the rear pulley to the pressure plate. They can also be individually balanced which it's obviously less effective. You need to decode if you are putting together a performance or stock engine and consider how long you would like it to last.
If it ain't broke, don't fix it! If it is, upgrade it!
- Marc
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Re: flywheel pressure plate question
As a rule, when a flywheel and clutch cover are balanced together some sort of marking is provided to ensure that the cover gets bolted up in the same relative location where it was when they were balanced. Look closely for punch marks, number stamps, or paint markings that match up. Really anal types will drill & pin the cover to the 'wheel to make it impossible to bolt them together "wrong".
IMO the only "right" way to balance a rotating assembly is to spin the crank alone* first and get it spot-on, then spin the crank+flywheel and rebalance at the flywheel only, then crank+flywheel+pulley (rebalance only at the pulley if needed), then the entire assembly including clutch cover. This way, the most likely component to ever need replacement (the cover) will have the least effect on the overall balance, followed by the 2nd- and 3rd-most likely components (the pulley and the flywheel, respectively). A flywheel or pulley isn't too difficult to balance solo, but a cover needs to be bolted to a flywheel (perhaps a surrogate that's been balanced already).
*Ideally, with a woodruff key and timing gear installed - but pragmatically, at that small of a radius there's very little difference between that and a "bare" crank or one with a woodruff key in place and no gear...it's not critical IMO unless the engine's going to be twisted to outrageous (7500+) RPM.
IMO the only "right" way to balance a rotating assembly is to spin the crank alone* first and get it spot-on, then spin the crank+flywheel and rebalance at the flywheel only, then crank+flywheel+pulley (rebalance only at the pulley if needed), then the entire assembly including clutch cover. This way, the most likely component to ever need replacement (the cover) will have the least effect on the overall balance, followed by the 2nd- and 3rd-most likely components (the pulley and the flywheel, respectively). A flywheel or pulley isn't too difficult to balance solo, but a cover needs to be bolted to a flywheel (perhaps a surrogate that's been balanced already).
*Ideally, with a woodruff key and timing gear installed - but pragmatically, at that small of a radius there's very little difference between that and a "bare" crank or one with a woodruff key in place and no gear...it's not critical IMO unless the engine's going to be twisted to outrageous (7500+) RPM.
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Re: flywheel pressure plate question
Thanks. My problem/question is that I have an engine and without thinking removed the flywheel and pressure plate and mixed them up with others. So short of taking the engine apart all I can do is have the pressure plate balanced to the flywheel and them just hope it fits the engine to some degree. It is a worn stock 2 liter that I just want to keep running and drive the bus.
Joseph
Joseph
- Piledriver
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Re: flywheel pressure plate question
Put any balance holes on the FW ~180 out (if possible) from any on the PP, and torque it properly.
Drive.
If it's far enough out to matter, you will notice it.
Drive.
If it's far enough out to matter, you will notice it.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Re: flywheel pressure plate question
Piledriver. Thanks. That helps alot.
Now the question of endplay. I've got it down to .006", or just almost within tolerance. Just how critical is a single thousandth of an inch? I have a shim on order from Germansupply that will probably get me to maybe .004".
Shim cost: $11.00
Shipping : $19.39
Now the question of endplay. I've got it down to .006", or just almost within tolerance. Just how critical is a single thousandth of an inch? I have a shim on order from Germansupply that will probably get me to maybe .004".
Shim cost: $11.00
Shipping : $19.39
- Piledriver
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Re: flywheel pressure plate question
Try a few different FW if they are all in good shape.
Take the measurement with full tq.
.006 is fine IMHO.
Generally with any clearance, to anything, I'd rather have a touch too much vs. too little anytime.
You DO have the distributor drive OUT, right?
Always pull it if the FW is coming off, otherwise you risk damage to the brass crank worm gear.
Metal does not self heal.
Take the measurement with full tq.
.006 is fine IMHO.
Generally with any clearance, to anything, I'd rather have a touch too much vs. too little anytime.
You DO have the distributor drive OUT, right?
Always pull it if the FW is coming off, otherwise you risk damage to the brass crank worm gear.
Metal does not self heal.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Re: flywheel pressure plate question
Oooops! Don't think I've ever heard that. I've been afraid to do more than pull the distributor for fear of screwing up something down there. Afraid of dropping ? down the case(horror stories heard). The distributor is still in because I saw it start rising up as I rotated the flywheel. So I fastened it down again.
Did I mess up major?
Thanks
Joseph
Did I mess up major?
Thanks
Joseph
- Marc
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Re: flywheel pressure plate question
So long as you've got a distributor in the hole to keep the pinion gear from climbing out of place all is well. Where you get into trouble is if the pinion gear climbs up out of its meshed location and you keep rotating the crank - that'll tear up the brass gear on the crank in a hurry. Personally I prefer to set the crankshaft endplay before installing either the distributor drive pinion or the pulley, but under normal circumstances neither should affect the endplay measurement. Minimum factory spec for endplay is .0027" which is too tight IMO. I shoot for .004-.0045" on a fresh motor; up to .006" is acceptable but .0035" is the bare mimimum for me.
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Re: flywheel pressure plate question
Then I'm going to go with .006". This is a somewhat tired engine. I'm going to try to get the rest of the fuel injection on and get the engine back in the bus. (and hope!).
Thanks
Joseph
Thanks
Joseph