Flywheel runout limits?
Thread Starter
Safety Car
Joined: Nov 2004
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From: going faster miles an hour...with the radio on in browns mills new jersey
Flywheel runout limits?
Hi, thought I'd pose this question here in the C3 section as you guys seem to be more into this sort of thing. I have .008 axial runout on a new flywheel. Is this acceptable? Both the crank flange and the flywheel mounting surface were deburred and cleaned. The measurment was taken just inboard of the pressure plate mounting holes. Thank you for your responses.
Melting Slicks
Joined: Apr 2000
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Originally Posted by nassau66427
Hi, thought I'd pose this question here in the C3 section as you guys seem to be more into this sort of thing. I have .008 axial runout on a new flywheel. Is this acceptable? Both the crank flange and the flywheel mounting surface were deburred and cleaned. The measurment was taken just inboard of the pressure plate mounting holes. Thank you for your responses.
.008" is way too much for my taste. *I* wouldn't accept any runout at all, but I'm a machinist and can do whatever needs to be done to get things perfect. Hmmmm....I might be able to talk myself into .001" TIR, but certainly no more than that.
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
Originally Posted by 45ACP
I'll assume you mean that you mean that you put the indicator on the machined surface and hand turned the whole works to get a total indicator reading of .008", as opposed to somehow measuring how much off center the whole thing runs in relation to the crankshaft centerline...
.008" is way too much for my taste. *I* wouldn't accept any runout at all, but I'm a machinist and can do whatever needs to be done to get things perfect. Hmmmm....I might be able to talk myself into .001" TIR, but certainly no more than that.
.008" is way too much for my taste. *I* wouldn't accept any runout at all, but I'm a machinist and can do whatever needs to be done to get things perfect. Hmmmm....I might be able to talk myself into .001" TIR, but certainly no more than that.
I wouldn't accept .008 either. I would start looking to see where that much runout came from. I would indicate the back of the crank and if a few thousands at this point carefully using a file or emery remove the high spot, taking the crank out is too much trouble so I would spend the time and remove the high spot on the crank flange. If that is not the problem then it is lack of parallism of the flywheel itself.Don't accept this much runout.
Le Mans Master
Joined: Jun 2002
Posts: 8,339
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From: I can walk to MA
EDIT: This is probably wrong - based on Norval's reply below.
It could be runout in both the crank flange and the flywheel.
Just like the brake rotors, you could rotate the flywheel in
relation to the crank (6 positions) and at least minimize it.
.008 sounds like a lot, especially if that is inboard of the friction
surface. It will be worse as you move outward.
It could be runout in both the crank flange and the flywheel.
Just like the brake rotors, you could rotate the flywheel in
relation to the crank (6 positions) and at least minimize it.
.008 sounds like a lot, especially if that is inboard of the friction
surface. It will be worse as you move outward.
Last edited by NHvette; Mar 31, 2005 at 02:14 PM.
Thread Starter
Safety Car
Joined: Nov 2004
Posts: 4,182
Likes: 94
From: going faster miles an hour...with the radio on in browns mills new jersey
Guys, thanks for the input. I returned the flywheel to my supplier. Hopefully I'll have better luck with the new, new flywheel. I should be getting it Monday. Thanks again.
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
Originally Posted by NHvette
It could be runout in both the crank flange and the flywheel.
Just like the brake rotors, you could rotate the flywheel in
relation to the crank (6 positions) and at least minimize it.
.008 sounds like a lot, especially if that is inboard of the friction
surface. It will be worse as you move outward.
Just like the brake rotors, you could rotate the flywheel in
relation to the crank (6 positions) and at least minimize it.
.008 sounds like a lot, especially if that is inboard of the friction
surface. It will be worse as you move outward.
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Le Mans Master
Joined: Jun 2002
Posts: 8,339
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From: I can walk to MA
Originally Posted by norvalwilhelm
I thought the flywheel was fixed in it's position. No chance to rotate. It is doweled to a single orientation.
had to mess with them. The only clutch I've done in years was a
Honda a few months back. I don't recall it was keyed in any way.
Did I check for runout ? Yeah - right - on a $100 car !? no.
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
Originally Posted by NHvette
You are probably right. My Chevys are all automatics ... and I haven't
had to mess with them. The only clutch I've done in years was a
Honda a few months back. I don't recall it was keyed in any way.
Did I check for runout ? Yeah - right - on a $100 car !? no.
had to mess with them. The only clutch I've done in years was a
Honda a few months back. I don't recall it was keyed in any way.
Did I check for runout ? Yeah - right - on a $100 car !? no.
