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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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Posted: Thu Nov 03, 2005 12:14 am Post subject: End-play shims |
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I HAVE searched and read all the old posts so don't nail me for that, BUT NO ONE SEEMS TO AGREE!
with .010" and .013" shims my endplay is .004" but thats only with two shims.
To get the right amount of endplay, with three shims, i would need two .008" shims and a .007" shim, but the pack of shims sold for setting end-play are no less than .095", which i'm guessing is because they would not be strong enough.
Adaze1 wrote: |
Did everyone forget about the steel and paper shim that comes in the gasket kit? I had to use the paper shim to get the correct endplay I was after. |
I have an 8 dowel crank so I would have to cut the paper gasket or drill the metal gasket and both ways would be sloppy at best. But if it worked it would put me in the ball park.
but...
danimal wrote: |
you should never use those shims with an o-ringed flywheel. |
turboblue wrote: |
The proper way to resolve this problem is to have the shim surface of the flywheel machined slightly to allow three shims. |
I really don't want to do that, but if I must then i have no choice but to dish out the cash.
or i could stay with two
[email protected] wrote: |
No problem with two. I have to do that sometimes with brand new flywheels and brand new cranks. |
but there are those that disagree..
mharney wrote: |
Three is to keep the net friction on each shim surface down. If they're working right, they share the rotation fractions. Two have to rotate more per revolution and theoretically will wear out sooner |
bugnut68 wrote: |
I had an engine once that was built by a local shop using only two shims for the end play and it ended up spinning the thrust bearing. |
stay with two shims or have it machined?
and why don't they make thinner shims?
who else has had a problem from using 2 shims? |
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Muffler Mike Samba Member
Joined: October 10, 2002 Posts: 1054 Location: Lawndale Ca.
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Posted: Thu Nov 03, 2005 8:03 am Post subject: |
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its all about friction and speed of the shims passing each other.
An example of no shims. Flanged crank that we use for racing. No shims, BUT we need to have .010" of end play to keep the expanding bearing from grabbing the crank because we have developed heat on it when whe stepped on the clutch pedal.
I think if you want to run 2 shims, you need to add in extra end play.
If you want to do it right and want a small end play, you need to get that flywheel surface cut down a little.
My old race/street motor was cut down quite a bit and i ran 4 shims. but i could also get away with .003" end play on a heavily abused configuration with out developing too much heat in the bearing.
thats how you can look at it.
why they are not thinner? imagine trying to put in aluminim foil for a shim... just to thin to suppport it self after a while. _________________ Muffler Mike
http://MufflerMike.com |
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gears Samba Member
Joined: October 28, 2002 Posts: 4391 Location: Tamarack, Bend, Kailua
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Posted: Thu Nov 03, 2005 8:09 am Post subject: |
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This illustrates the reason for figuring the shim selection on the work bench, before even installing the crank in the case. That way you can clearly see the #1 bearing/flywheel clearance from every possible angle. |
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Glenn Mr. 010
Joined: December 25, 2001 Posts: 76760 Location: Sneaking up behind you
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Posted: Thu Nov 03, 2005 9:01 am Post subject: |
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gears wrote: |
This illustrates the reason for figuring the shim selection on the work bench, before even installing the crank in the case. That way you can clearly see the #1 bearing/flywheel clearance from every possible angle. |
Agreed...
I like doing it before so I can use a low tech feeler gauge. _________________ Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"
Member #1009
#BlueSquare |
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keifernet Samba Search & Rescue
Joined: May 11, 2002 Posts: 19395 Location: Samba Center for Behavioral Science
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Posted: Thu Nov 03, 2005 12:33 pm Post subject: |
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You don't state if your crank is counterweighted aftermarket or just a stock VW that is 8 dowelled.
I have found that the aftermarket cranks need some minor clearancing as the cheeks can rub against the main bearing webbing in the case just a bit and when you assemble ( even if you checked the end play on the bench with the crank, rear main and flywheel) the crank does not have the lateral movement and your calculations are off.
Another reason to always assemble just the crank and mains and rotate and check for signs of the crank rubbing inside the case. |
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turboblue Samba Member
Joined: October 09, 2003 Posts: 4216 Location: Central Indiana
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Posted: Thu Nov 03, 2005 2:11 pm Post subject: |
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Along the lines that keifernet pointed about about crankshafts, Scat cast cranks are notorious for the large radius at the thrust bearing.
I've had to machine the thrust bearing at the inside radius to clear that huge radius.
If the bearing hits the radius before all the endplay is pulled out your readings will be off too. _________________ Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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Posted: Thu Nov 03, 2005 3:30 pm Post subject: |
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12.5 lbs lightened from brazil.
they sell 8 dowel flywheel gaskets for setting endplay. why shouldn't these shims be used with an o-ring flywheel? |
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turboblue Samba Member
Joined: October 09, 2003 Posts: 4216 Location: Central Indiana
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Posted: Thu Nov 03, 2005 3:34 pm Post subject: |
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mitcharvey wrote: |
12.5 lbs lightened from brazil. |
I'd bet that's a cast steel flywheel.
Notorious for being out of spec.
Got a good way to measure it?
Check it from the surface the crankshaft bottoms out on to the surface the shims ride on. _________________ Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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Posted: Thu Nov 03, 2005 3:55 pm Post subject: |
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.325 all the way around |
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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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Posted: Thu Nov 03, 2005 6:46 pm Post subject: |
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anyone know why the flywheel gaskets shouldn't be used? |
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turboblue Samba Member
Joined: October 09, 2003 Posts: 4216 Location: Central Indiana
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Posted: Fri Nov 04, 2005 7:59 am Post subject: |
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mitcharvey wrote: |
.325 all the way around |
Well I just measured 3 and got .322, .323 and .325.
The first two were OEM German and the last one was a chromoly aftermarket.
You never did say what your crank type was. _________________ Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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turboblue Samba Member
Joined: October 09, 2003 Posts: 4216 Location: Central Indiana
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Posted: Fri Nov 04, 2005 12:19 pm Post subject: |
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Not a problem mitch.
Are you checking the endplay without the piston/cylinders installed?
Can you take your engine back apart?
Got something I want you to check. _________________ Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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Posted: Fri Nov 04, 2005 12:23 pm Post subject: |
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i've got everything assembled... its only waiting for pushrods and what ever will set the endplay correctly until it goes in. how important is it? |
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turboblue Samba Member
Joined: October 09, 2003 Posts: 4216 Location: Central Indiana
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Posted: Fri Nov 04, 2005 1:12 pm Post subject: |
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I'm worried the thrust bearing is not seating against the crank properly.
I've got an engine torn down that I can send you a picture of where my concerns are.
Endplay should always be set without the pistons and cylinders installed.
Maybe that is causing the problem. _________________ Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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mitcharvey Samba Member
Joined: October 24, 2004 Posts: 87 Location: lompoc, cali
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Posted: Fri Nov 04, 2005 1:23 pm Post subject: |
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turboblue wrote: |
Endplay should always be set without the pistons and cylinders installed.
Maybe that is causing the problem. |
I assembled top end after measuring endplay...
could you send that pic? i would really like to see it
Its a new crank and flywheel, do you really think it is the thrust bearing?
like [email protected] said:
Quote: |
No problem with two. I have to do that sometimes with brand new flywheels and brand new cranks. |
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turboblue Samba Member
Joined: October 09, 2003 Posts: 4216 Location: Central Indiana
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Posted: Fri Nov 04, 2005 1:34 pm Post subject: |
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You have a PM _________________ Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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