clutch problems

[Kenneth Cole]

Hi
I have a 61 m37 with a Dodge 318 in it mating up to the stock tranny. This is an ugly truckling conversion, It shifted ok for a short time (2 days) and then it started to shift hard and lock up. I noticed that I now had about 6 inches of clutch travel. I got home and adjusted the travel to about an inch tried it again and the travel went back to about 6 inches. I pulled the tranny and it appears that the pressure plate fingers have moved forward and stuck.
I think that in the process of getting the clutch to disengage enough to allow me to shift I have collapsed the pressure plate.
My questions are:
Does this sound right?
Could it be that my problem is not with the clutch but with the tanny not allowing me to shift and I thought it to be the clutch?

Maybe the top cover has some problems?

Is there a way that I can check out the top cover?

Any other advice?

Ken

[Matthew Welcher PWA]

Ken, several parts to both your question and answer. It does sound like the pressure plate collapsed. Was it a new Pressure Plate? On your transmission, had you ever been through it? as far as had any prior issues with it?
The shift tower of your transmission, is the shifter cane really loose in the top? Had you had problems getting it in and out of gear?

I have had some experience with a V8 In an M37 but never with the stock transmission, always with the NP 435. Is this the set up that uses the adapter plate?

And if so was everything lined up really well?

Just a few questions to think on, Hopefully Charles Talbert will see this and possibly have a few more suggestions for you.

Matt

[Kenneth Cole]

Hi Matt
The Tranny is the NP420 and I had an adapter made from the ugly truckling web sit pattern. My guess is that it is pretty true, I have no trouble installing the tranny and the bolts line up well. That's the best I can say.
The shifter does seem to be sloppy but don't know how much is to much .I have trouble with both shifting into gear without grinding and sometimes cannot pull the shifter out of gear. It will also pop out of high gear when I back off the gas.
The pressure plate is brand new and had no issues with the tranny when it was with the stock engine.

Ken

[Charles Talbert]

Ken, you could have issues in several areas based on your explanation. Popping out of any gear is most likely an internal, inside the trans issue. Very possibly in the shift rail mechanism, or problems on the main shaft.

If you have a custom machined adapter plate, this can be a very problematic component. First question, how precise were the drawing dimensions? The best machinist is only as good as his directions. I have seen MANY adapter plates be the cause of major alignment issues, which typically leads directly to clutch problems. A very minor machining error can literally cause a major pain, breaking the center out of the clutch disc, breaking the trans input shaft, etc. I have seen the ends of the pressure plate fingers very slightly contact the surface on the front bearing retainer that the release bearing collar slides on causing jamb ups, etc. Anytime you are changing from an original set up, extreme care must be exercised in all areas, checking, rechecking literally EVERYTHING. There is no such thing as simply doing these changes expecting a simple bolt it up and go ending, UNLESS someone has built the components for you and paid extreme attention to ALL the possible issues. Even then an exactly correct assembly using the best parts is up to the installer.

Loose motion in the shift tower is not good, we have rebuilt many with a good result. If it is loose enough, it can very well be the cause of shifting and popping out of gear issues. Hard for an untrained eye to check out these issues. Goes back to an old saying from when I was a kid, if one is unaware of exactly how a component is supposed to work when all is correct, it will be extremely hard for one to repair any problem with the component, simply because he does not recognize a problem although he may be looking right at it. Long story short, if you don't understand how it works, you can't fix it.

This is all I know to offer without more detail of the issue.

[Matthew Welcher PWA]

Thanks Charles, great advice!