Flywheel bolts different?
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
Flywheel bolts different?
Can someone tell me the difference in automatic transmission (flexplate) bolts and manual transmission (flywheel) bolts? I seem to have some interference on my clutch plate springs with the bolt heads on the flywheel... 
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
anyone? Are the automatic flexplate bolts taller in the head of the bolt than Manual flywheel bolts? Seems to be the only possability of the springs on the new clutch disc touching them...
Melting Slicks
Joined: Dec 2000
Posts: 2,198
Likes: 2
From: Eastern Connecticut
Flywheel bolts and flexplate bolts both have thin heads. The difference is only the length. You shouldn't use the wrong ones - too long and they hit the back of the block, too short and they won't hold the flywheel. They should protrude just a tiny amount through the crankshaft flange.
If you are using the correct thin head bolts, the reason your clutch disk is hitting the bolts is it's on backwards. The springs go out towards the cover.
Hope this helps.
Joe
If you are using the correct thin head bolts, the reason your clutch disk is hitting the bolts is it's on backwards. The springs go out towards the cover.
Hope this helps.
Joe
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
Joe...I have the thin head bolts on it...the clutch disc is marked and says "this side towards flywheel". The springs proturde out from the disc much lees on the flywheel side than on the pressure plate side but that small protrusion in the front seems to be just catching the heads of the bolts. The disc is on correctly and the flywheel is a brand new aluminum flywheel. Any other ideas? Thanks
Melting Slicks
Joined: Dec 2000
Posts: 2,198
Likes: 2
From: Eastern Connecticut
Hmm, you ruled out my other idea, the flywheel has been surfaced too many times. If nobody else has any ideas you might have to go to the manufacturers for advice. Perhaps you should list the names here in case someone else has the same stuff. Sorry I can;t help. Joe
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
the clutch is a 10.5" Zoom and this is the flywheel
http://cgi.ebay.com/ebaymotors/ws/eB...964741965&rd=1
http://cgi.ebay.com/ebaymotors/ws/eB...964741965&rd=1
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
HI
When I changed the clutch and resurfaced the flywheel, I used new bolts ( ARP ). Those are different from the ones that where installed.
The old once where 6 point heads, the ARP are 12 point bigger diameter heads. The old bolts used washers, the ARP bolts had a danger note with them to not use any washers with them ?
This of course brings them further away from the clutch ( springs ).
Would that help ? I think I ordered from SUMMIT.
Günther
When I changed the clutch and resurfaced the flywheel, I used new bolts ( ARP ). Those are different from the ones that where installed.
The old once where 6 point heads, the ARP are 12 point bigger diameter heads. The old bolts used washers, the ARP bolts had a danger note with them to not use any washers with them ?
This of course brings them further away from the clutch ( springs ).
Would that help ? I think I ordered from SUMMIT.
Günther
Instructor
Joined: Jun 2004
Posts: 235
Likes: 0
From: NE
I bought some arp bolts for a new flywheel a couple weeks ago. The ones I bought were part number ARP-200-2802
There is something about two different head sizes that summit mentioned to me when I ordered these and that the larger ones could be too large in some applications. The ones I ordered are the larger head size (they take a larger socket). I didn't quite understand what these larger ones would interfere with since they go into a recessed area on the flywheel.
I'm not sure if this info is any help to the problem you are having.
There is something about two different head sizes that summit mentioned to me when I ordered these and that the larger ones could be too large in some applications. The ones I ordered are the larger head size (they take a larger socket). I didn't quite understand what these larger ones would interfere with since they go into a recessed area on the flywheel.
I'm not sure if this info is any help to the problem you are having.
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Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
Did you install washers with the ARP bolts ?
Without washers , as they mention to do , this bolts are very long and nearly touching the block casting.
I actually ground about 2 threads away of each bolt to assure clearance.
The ARP bolts have the exact same lenght as the old 6 point bolts had , but the old bolts had locking washers installed, so rather thick washers.
Günther
Did you install washers with the ARP bolts ?
Without washers , as they mention to do , this bolts are very long and nearly touching the block casting.
I actually ground about 2 threads away of each bolt to assure clearance.
The ARP bolts have the exact same lenght as the old 6 point bolts had , but the old bolts had locking washers installed, so rather thick washers.
Günther
Instructor
Joined: Jun 2004
Posts: 235
Likes: 0
From: NE
I didn't use washers... a small sheet that came with the arp bolts said not to. I did take a look at how far they were coming through. They were sticking out a little, but it appeared like a safe distance from the block.
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Originally Posted by Jclgodale3
could I have a machine shop machine just the bolt suface down about 3/16" for the clearance I need? Would this compromise the flywheel strength?
You may want to contact Zoom and order a flywheel from them (if they sell them), or ask for some options that will work with their disk.
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
but the springs aren't touching the flywheel...only catching the heads of the bolts. Thats why I thought a small machining then going without the washers on the bolts would create the clearance I need. Bad idea?
2nd Gear
Joined: Sep 2022
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They are not real clear about this on Summit. Please beware!
2nd Gear
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Is my vette stock?? HAHA
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what is the clutch disc part number. They offer them with reversed springs so they would be on the wrong side in your application...its the only thing I can see causing your issues.Or you have a the wrong disc for your flywheel.
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