The Stovebolt Site Forums The Shop Area The HiPo Shop CenterForce Pressure Plate and Clutch in a Task Force

I have a 1965 348 rebuilt engine in a 1957 Chevy 3/4 to truck (NAPCO). I installed a CenterForce Clutch and pressure plate appropriate for the engine. I also have the long throwout bearing. The clutch fork is the cast type. The problem is that the transmission will not go into gear (engine running). It appears the clutch is not engaging all the way. All the measurements and fork angle seem correct according to the CenterForce spec. sheet. When I try to compensate the fork linkage to get increase throw-out bearing travel, I either break or lose the pivot pin holding the fork to the pivot ball.
Measuring, the Centerforce assembly is about an inch shorter that the stock one that is on my 283 which was originally in the truck and worked fine. I'm wondering if the Centerforce pressure plate/clutch assembly is just wrong for the truck application (bell-housing and forged fork). Any opinions before I do another un-install would be much appreciated.
Thanks,
don

It may be the throught out bearing. You may need the short depending on which pressure plate you have. Some have taller finger on the pressure plate which translates to needing short bearing.Larry

I agree about the TO brg. Generally the newer style clutches use the short brg. Can you contact Center force & get there thoughts on it. If it has the "Beehive" type pressure plate were the fingers protrude out to the outer edge of the pressure plate, you need the short brg.

If it won't go into to gear while the engine is running, sounds like the clutch is not releasing from the flywheel/pressure plate.

One problem may be the disc is in backwards.

Do the gears grind when you try to put it into gear with the engine running? If so, then the clutch is not being released.

What you guys are saying is the opposite of where I was going. But upon reflection it makes absolute sense. The gears do grind with the engine running. I think I need to try the shorter throw-out bearing as suggested. Thanks for the insight. I'll let you know how it works out.
don

Sounds like the clutch is simply out of adjustment. Remove the free play in the clutch by adjusting the 2 1/2 inch nuts on the d- shaped rod.

Generally the clutches come with the proper throwout bearing when they are sold as a kit.

I am unfamiliar with center force clutches. Are they a "borg and beck" type, or a diaphragm type. I have a 12 inch diaphragm clutch in my 59 jimmy.

I am not an expert on CenterForce clutches (or any). I have tried adjusting and even making different length "D" rods. Two things:
- I did not get the throw-out bearing as part of the clutch
kit, however they do offer a short and long one.
- The install is in a 1957 truck with a 1965 348 using the
same bell-housing as the 283 I removed.

The CenterForce tech support wasn't much help, apparently the bell housing is too old to be on their "supported list."

I didn't mention that when I try to start the engine, select a gear, clutch pedal depressed, it is still in gear. That leads me to the logic of the prior posts suggesting too the need for the shorter throw-out bearing.
Thanks,
don

Don, are you using a Centerforce type I pressure plate or are you using a II or III? What year bellhousing are you using? If I remember your earlier posts you added side motor mounts when doing your engine install. I have included a link for an information sheet that Centerforce put out regarding GM clutch forks and through out bearings.

http://www.centerforce.com/images/store/midway-industries-inc/CTF-CF165473-I93GM001.pdf

Don:
Thanks for the PDF. Since mine is a cast fork, I need the N1430 release bearing (as per the spec. sheet). I found the same release bearing at NAPA for less money.

Yes, the 348 is in (my progression has been 235, 261, and 283 engines installed). Needless to say, I get a lot of feedback about making up my mind. (Now I'm wondering about a 409)

I will see what happens this weekend.
don

Once you get the 348 working good it will be a piece of cake to upgrade to the 409, minor differences such as dipstick location.

Thanks for all the replies, as usual all good advice for determining what the problem could be. You all put me on the right track for looking at the problem logically. Ends up it was the throw-out bearing. The stock one was too long, I got the short one and I am back in business. Although I feel a bit dumb not diagnosing this problem properly myself, I did make some improvements (e.g., re-curved the Hurst shifter), during the multiple removals and installs of the transmission. Also, I am a lot better at transmission installs now. Thanks again,
don