shift shaft conical set screws, how tight? Options

[malcolm2]

Ok to avoid the "screw won't come out" issue again, let me ask.....What is the object here? I am installing the long under the engine, curved shift shaft on my 75, side shift tranny. The coupling by the fire wall gives me no issues. However the one at the shift console does.

I assume you want to screw in the set screw until the shaft has NO PLAY, correct?

It ended up pretty tight, but I have no play. I guess it could it have wiggled around over the years and increased the size of the hole in the shaft.

Thoughts??

[malcolm2]

All good points. But I am asking about the play (free twist) in the shaft after the set screw has been set. Or as a way to tell if it is, let's say, DEEP enough.

I too had a VERY tight experience and ended up cutting the cast coupler off.

[Bartlett 914]

All good points. But I am asking about the play (free twist) in the shaft after the set screw has been set. Or as a way to tell if it is, let's say, DEEP enough.

I too had a VERY tight experience and ended up cutting the cast coupler off.

Must be none! Sometimes these get loctite in place. If you don't heat them on removal, you can have problems. Any wiggle of the shaft in the coupling WILL lead to a failure. It may be the tapered hole in your shaft may be ovaled. it this is the case, it must be either repaired or replaced.

I did recently have one where the welds were cracked. This caused some movement but it was not in the coupling itself. I think these welds breaking is a common problem. It was not real apparent. The shaft was somewhat stuck in position. Only under some load could you see movement.