Do the flywheels have to be balanced?
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Do the flywheels have to be balanced? The reason I ask is that C5's need the flywheel to be balanced when they're reinstalled because the engine relies on the flywheel to balance the motor. Now, LS1's are the same whether they're in the F-Body or Y-Body so has this affected anyone? I'm gonna be the first to put the big bad RAM in my C5 <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> and I want to be sure that resurfacing the flywheel won't cause driveline vibration. I will have the flywheel rebalanced but I just want to make sure. Thanks.
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Re: Do the flywheels have to be balanced? Could this by why I am getting a slight vibration?
I got my flywheel re-surfaced, but I dont think they balanced it.
hmm Do they automatically balance it?
I got my flywheel re-surfaced, but I dont think they balanced it.
hmm Do they automatically balance it?
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Re: Do the flywheels have to be balanced? Not likely that a resurfacing shop would rebalance without a charge. The LS1 flywheel is neutral balanced, but if it is not mounted properly for resurfacing it *could* be cut on a slight angle which would cause the clutch to mount with a slight wobble. This is why it is critical for the flywheel to be located off the crank flange for resurfacing.
Re: Do the flywheels have to be balanced? yes dont get the wrong idea of the term 'balanced'
the ls1 itself in either car is internally balanced, then has a harmonic damper up front it does not rely on the flywheel for any sort of 'counter'balance.. heck, auto's dont even have flywheels to balance if it was needed.
it shouldnt need to be 'balanced' like you would balance a tire either.. if they need to add/remove weight that wasn't originally there when the flywheel was brand new, they they f'd it up by cutting into it wrong as said above. a proper resurfacing will cause no vibration.
the ls1 itself in either car is internally balanced, then has a harmonic damper up front it does not rely on the flywheel for any sort of 'counter'balance.. heck, auto's dont even have flywheels to balance if it was needed.
it shouldnt need to be 'balanced' like you would balance a tire either.. if they need to add/remove weight that wasn't originally there when the flywheel was brand new, they they f'd it up by cutting into it wrong as said above. a proper resurfacing will cause no vibration.
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Re: Do the flywheels have to be balanced? If you change flywheels you must transfer the weights from the old one to the new one, at least you do on the C5's (don't see why it'd be any different on any LS1). It's in the Helm's manual and many fellow CorvetteForum members have had shops NOT do this and they get horrible vibrations from not transfering the counter sunk weights in the original flywheel to the new one. I agree however that the resurface should not affect it but I'm having mine measured before resurfacing and after to make sure it's balanced like it was when it was removed.
Re: Do the flywheels have to be balanced? well i have never heard of these weights on any flywheel.. ever but if gm put them on then i would say to leave them on.
just to add.. i like many others on this board have factory gm flywheels and they have, nor have provisions for any weights to be attached to them
there are definitely no balancing weights on the f-body flywheel.
what holds this weight in? what is the assembly like?
you sure you are not talking about the pressure plate guide dowells around the perimiter of the flywheel? these do need to be removed for surfacing then SHOULD be reinstalled unless you are installing a clutch that does not use them. they are spaced evenly around the flywheel so their absence would not change the balance.
i have a picture if you would like to see what one looks like. just email me. dave
just to add.. i like many others on this board have factory gm flywheels and they have, nor have provisions for any weights to be attached to them
there are definitely no balancing weights on the f-body flywheel.
what holds this weight in? what is the assembly like?
you sure you are not talking about the pressure plate guide dowells around the perimiter of the flywheel? these do need to be removed for surfacing then SHOULD be reinstalled unless you are installing a clutch that does not use them. they are spaced evenly around the flywheel so their absence would not change the balance.
i have a picture if you would like to see what one looks like. just email me. dave
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Re: Do the flywheels have to be balanced? Sure, email it to me: lprocter@hotmail.com Maybe that's what I'm referring to <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
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Re: Do the flywheels have to be balanced? Here's the info right from the manual (this applies to those that may put a NEW flywheel on or use another old resurfaced flywheel to put on their LS1 instead of their original one.):
If replacing the manual transmission flywheel, note the location of any existing balance weights (relative to the position of the flywheel locating hole). Install new balance weights into the new flywheel, if applicable. The flywheel balance weights must be installed into the new flywheel in the same location as the old flywheel. A properly installed balance weight will be either flush or below flush with the face of the flywheel. Two different size weights are available - 15.8 mm (0.625 in) and 25.4 mm (1.0 in).
This is a pic of the weights that must be transferred to the NEW Flywheel from the old one if you change to a different flywheel.
<img src="http://home.insightbb.com/~ominousvette/flywheel.gif" alt=" - " />
Also, here's some info regarding the A4's:
DO NOT remove the propshaft hub or flexplate from the automatic transmission engine flywheel. The flywheel, propshaft hub, and flexplate are balanced as an assembly. If service is required, the entire flywheel assembly should be replaced.
If you have your original flywheel resurfaced make sure its location relative to the crank is scribed or market and reinstalled at this location and you'll be fine.
<small>[ May 20, 2002, 11:04 AM: Message edited by: NastyC5 ]</small>
If replacing the manual transmission flywheel, note the location of any existing balance weights (relative to the position of the flywheel locating hole). Install new balance weights into the new flywheel, if applicable. The flywheel balance weights must be installed into the new flywheel in the same location as the old flywheel. A properly installed balance weight will be either flush or below flush with the face of the flywheel. Two different size weights are available - 15.8 mm (0.625 in) and 25.4 mm (1.0 in).
This is a pic of the weights that must be transferred to the NEW Flywheel from the old one if you change to a different flywheel.
<img src="http://home.insightbb.com/~ominousvette/flywheel.gif" alt=" - " />
Also, here's some info regarding the A4's:
DO NOT remove the propshaft hub or flexplate from the automatic transmission engine flywheel. The flywheel, propshaft hub, and flexplate are balanced as an assembly. If service is required, the entire flywheel assembly should be replaced.
If you have your original flywheel resurfaced make sure its location relative to the crank is scribed or market and reinstalled at this location and you'll be fine.
<small>[ May 20, 2002, 11:04 AM: Message edited by: NastyC5 ]</small>
Re: Do the flywheels have to be balanced? well i was wrong, thats definitely a balance weight.
"note the location of any existing balance weights (relative to the position of the flywheel locating hole). Install new balance weights into the new flywheel, if applicable."
i think this explains it, i dont have any weights in mine nor have seen any in the other clutches i've done. so i havent had to remove or replace weights.. because not all of them have em'
solution 'if you have weights, then put em where u got em from, if you dont, ur good'
"note the location of any existing balance weights (relative to the position of the flywheel locating hole). Install new balance weights into the new flywheel, if applicable."
i think this explains it, i dont have any weights in mine nor have seen any in the other clutches i've done. so i havent had to remove or replace weights.. because not all of them have em'
solution 'if you have weights, then put em where u got em from, if you dont, ur good'
Re: Do the flywheels have to be balanced? On a street car(regular), Turn flywheel and go. On a high perf motor, Balance is a must in my book. An enginer explained it to me this way. Have you looked at a fan and it looked like it was turning slowly in the opposite direction of the way it was realy turning? That's the way harmonics works. He said it's 'reverse whirl mode'. The vibrations are fighting each other untill failure is the result. This was discovered on prop (airplanes) failures way back when. Low RPMs won't matter. But when you start winding it, your more apt to feel a vibe. I've resurfaced a many a flywheel. Yes, you can mount it right and 99% no problems. But wrong, and you feel a viberation on engaugement. In other words, Low dollar mods, cut and go. High dallar mods, Insurance. Just my $.02. Yes I've even balanced my flexplates when balancing an assembly. <img border="0" alt="[chug]" title="" src="graemlins/gr_chug.gif" />
