The Stovebolt Site Forums The Shop Area Engine Shop Flywheel Shims???

So I am about to swap my 216 for a 250.

The engine I bought has a flexplate (auto trans), so I am starting to gather parts for the clutch since I'll be using my SM420.

While looking up a new flywheel and a clutch kit, I noticed flywheel shims (not starter shims) in various thicknesses. I will be using a new flywheel. Are these shims needed in stock form or are they just if you had the flywheel turned at some point. I admit I have never seen those before.

Larry W.

I am going to just throw this out there. I have read when you balance a flywheel you do it with a clutch and flywheel together. Maybe that's why the shims are there. I have no experience in this but read it in a few books

Removed my response

Ok,

At first I could not find a description of what they were for, even where they were being sold. I did finally find that description on Summit. Apparently they are intended to correct the thickness lost after surfacing a flywheel. They go between the crank and the flywheel.

http://www.summitracing.com/parts/atp-gs3?seid=srese1&gclid=CLj5kfCuwskCFdEXHwod88cEMw

Quote from site:
"Get proper spacing and engagement with ATP flywheel shims. These steels shims offer you the adjustment that you need after having your flywheel resurfaced. Improper clutch location can be dangerous and uncomfortable. Make it right with ATP flywheels shims."


Larry W.

Looking at the application list unless I am wrong, this shim is for V8's, not 6 cyl.

Here's a thought- - - -the only time it might be necessary to shim a flywheel after surfacing it would probably be when using the non-adjustable hydraulic throwout bearing that surrounds the transmission snout. Any of the stovebolt clutch linkage with the fork-type throwout bearing actuator and screw-adjustable linkage would make the flywheel surface plane pretty much a moot point.
Jerry

Along similar lines to Jerry's reply, here's a quote from the
Hotrodders forum:

"I grind flywheels daily. If more than .020 is removed from
the friction surface on a hydraulic T/O clutch setup. The
clutch pedal height will not be correct and won't release
as the system was designed.
Customer will not be happy. You will get to re-do the
job correctly.
Flywheel shims are available in several thickness:
.020-.035-.050-.085 are a few I have in stock."

I've personally never heard of using one but then again,
I've never wrenched on any newer vehicles.
Denny Graham
Sandwich, Illinois

Hydraulic clutches have been around since the late 1950's, possibly before that. My 58 Austin Healey 3000 had one, also the 57 MGA I owned. Ditto for the 65 Dodge D-100 pickup with the 318 V8 I used as my first Diesel truck road service vehicle. All of those had a slave cylinder mounted outside the bellhousing, and a regular threaded clutch adjustment. The ones that fit inside the bellhousing aren't adjustable, and they rely on the proper spacing between the front of the transmission bearing retainer and the flywheel friction surface to work properly. The explosion-resistant scattershields the drag racers used before they got smart and started running automatic transmissions were some of the first ones I saw with the internal slave cylinders.

Edit: Spacing the flywheel back could create problems with the starter pinion gear engagement- - - -there's no free lunch!
Jerry

I notice you said the engine was hook up to automatic transmission before.
Shims are sometimes use to obtain the right spacing between the torque converter and the flex plate/ flywheel in order to prevent damage to the automatic transmission pump gears.
As the torque converter has to be 1/8" out
As flex plate / converter mounting pads vary in thickness
So shims maybe use whether you have a automatic or standard shift in order to obtain the right clearances between the transmission and engine.

Currently rebuilding a powerglide