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Tips
Tips

trf clutch replacement

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Soup,

You want a bolt with as little thread as possible
touching the metal sides of hole. Take the fork and
shaft with you to a specialty fastener shop. Play
around with different lengths.

You might have to grind a little thread off but try
to avoid that. I think heat effects the strength of
the bolt.

good luck

d
 
The smooth shaft of the bolt between the thread and the bottom of the bolt head is referred to as the grip length of the bolt. You can buy AN bolts (aircraft bolts) with grip lengths in 1/8" increments. So you can measure what the length of the smooth part of the bolt should be and get just about the right length. You can then use a washer if the grip is a little longer than you need. That way the part of the bolt that is in shear is the full bolt diameter and not the smaller diameter of the thread (just repeating what Tinster already said).

You can get AN bolts at any of the usual aircraft or auto racing supply houses. I generally buy mine from Aircraft Spruce and Specialty (you can Google them and order on-line). I think a 5/16" bolt is going to be in the $0.75 range. If you're buying a lot of bolts, it can get expensive but for one or two it's not too bad. On my racing cars, I try not to use anything but AN bolts in stressed applications.

Bryan

Edit: You can also get them pre-drilled for safety wire if you're worried about that one working loose too. That adds about $0.20 to the price.
 
Bryan,

That's real interesting stuff. I wondered what the bolt
guy was doing in the back when we were trying to get the
grip length just right.

I used a nylok and Loctite blue. That was before I knew
about metal lock nuts.

d
 
I've always used 1/4" roll pins (sometimes refered to as spring pins) to reinforce the fork on the shaft. Drill a 1/4" hole and hammer it in. I've never seen one loosen or come out.
 
Thanks guys!! Once again great input. The roll pins sound like the easiest way to go. I'll have to look into this option further. I'm off to try and find both types at an auto shop store. I'll keep you posted on my progress and thanks again.
 
I just drilled my fork & shaft with a 1/4" hole. A 2" length bolt from home depot had sufficient shank (non-thread) area to fit the entire length. Sliding on a lock washer followed by nut tightened up nicely. This leaves about a 1/4" length of thread protruding which is easily sawed away. A 1/2" length roll-pin fits almost perfectly.
 
I'm ready to this but a little confused, should I be tapping just the shaft or just the fork?
 
Remove the shaft and fork from the tranny bell housing. Fasten the fork back onto the shaft and tighten it down with the original pin. Now, the drilling is best done with a drill press to get a nice straight hole but I did mine with a hand drill. Use a center punch to set your starting point on the flat surface side of the fork then drill away. You drill through both the fork and the shaft.
 
71tr, thank you and I have the fork and shaft ready for the drill press and understand that I need to drill through both the fork and shaft. What I'm not sure about is do I thread both the fork and shaft? It seems that I would only want to thread the shaft. In that way the bolt wll pull the shaft against the fork to prevent the two from rocking/moving and in turn limit force on the original pin.

How has everyone else been doing this??
 
No, there is no threading involved. You simply drill a hole through both items and stick a snug fitting bolt or roll pin in there. The goal is to provide a secondary securing location to take the load off the original fork pin.
 
No threading at all, that is interesting. I guess I'll be using locktight or something similiar on the bolt as well.

Thanks again
 
As I was sitting here completing an online defensive driving course, it dawned on me that I had not updated and thanked y'all for helping me with the transmission conversion/clutch replacement. Everything went fairly smoothly and I'm very pleased with both the clutch and the new a o/d tranny.
 
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