The Stovebolt Site Forums The Shop Area Engine Shop T-5 in a 41 Clutch Not Releasing?

I just installed a T-5 in my '41 using the adapter from Buffalo and an 11" clutch disc (RCF4212). It's acting like the clutch is not fully releasing. With the clutch in I can not shift into gear. If I start the engine with it in gear it creeps forward even with the clutch disengaged. When the clutch is fully depressed I measure about 90 thousandths clearance between the disc and flywheel. How much should it be? I also replaced the pilot bushing. Is it possible it needs to be driven in further? I did check for clutch disc movement by installing it and the transmission without the pressure plate and throwout bearing and it seemed to have plenty of movement. What did I miss? I'd like to have a few hints before I tear it down again. Thanks.

Having walked that same path during my T5 install on a 56 235 (6 volt flywheel) I found that even though you have clearance at the outer edge of the disc it is flexing and binding up in the center....that's where your drag is coming from. I've documented the process that I used in extending the splines and verifying that the disc will actually slide far enough back to completely release in my webshots Shoebox album. (page 5 or 6) I used the rcf-4201 disc and haven't had any release issues since I made the modifications and have switched it to a 60-235 with a 12 volt flywheel. Hope this helps.

Dave

I hear this is a common problem with t-5 conversions if not measured and checked before installation.

What happens is the internal splines in the clutch disc run out of external splines on the input shaft to slide on, so it forces the clutch in to the flywheel and drags.

I have heard of people putting washers between the trans and bell housing to solve this. I would not do it that way.

I also hear that there is a clutch disc out there that works without modification to anything. I forget what applicaion it is intended for.

Personally I would consider milling a portion of the clutch disc hub off before I extended the splines on the input shaft.

I have not installed a t-5 in anything.....
Grigg

Harold,
How thick is your adapter plate? 'Cause mine is about 3/4" thick. I've just reuploaded all my pictures and you can see my whole process in these pictures. Click

I think my adapter plate is 3/4" thick. I'll measure later today to see. I installed the transmission with the disc but without the pressrue plate first and thought I had plenty of clutch disc movement.
John, I see you also used the 11" clutch disc? The 11" disc I have is about 1/8" or less wider than the pressure plate. I'm wondering if there is a chance the back edge of the disc is hitting the pressure plate cover? But I also notice you cut the input bearing retainer about 1/4", I didn't because I thought it had plenty of movement. Maybe I'll cut it anyway.

Well, my adapter plate is 1/2" not 3/4". It's sounding like the bearing retainer is where I should focus in addition to taking some better measurements.

It was the throw-out bearing. I took it out and re-measured everything today and all the measurements said it was OK and I couldn't see anyplace that was rubbing. I had bought a new T/O bearing by cross-referencing the old ones number. The new one is about the same overall length but the length from the fork groove to the face of the bearing was 140 thousandths shorter than the old one. I put the old one back in and it works fine. I thought I had too much free-play anyway.

The T-5 sure makes it more driveable but I miss the nostalgic whine of those old non-synchronized gears.

Thanks to everyone who responded.