TR6 J Type Overdrive High Pressure Filter Cap-Major Problem

[M_Pied_Lourd]

Hi Guys,

I have what I think might be a major problem.

As part of my Spring maintenance, I decided to clean the filters in my J Type Overdrive. Everything went fine taking the high pressure filter out. Today, after cleaning the filter, I tried to reinstall and the cap that holds the filter in will not thread back into the aluminum transmission case cleanly. I've tried cleaning with a tooth brush and carb cleaner and everything is impeccably clean. The cap only goes back in about 1/2 way before it stops dead...so, I believe I have damaged the threads on the aluminum case.

In order to fix this, I think I'm going to need to find a tap to chase the threads in the case.

The steel cap looks to be coarse thread. Does anyone happen to know the tap size that I would use to chase the treads in the transmission case?

Any help would be appreciated.

Cheers
Tush

 

[TR3driver]

If the threads are that badly damaged, the damage should be very obvious. Usually bunged threads just gradually bind rather than stopping suddenly.
I'd be looking for something else that is stopping the plug from going in.

 

[M_Pied_Lourd]

It's got me baffled that's for sure. I cannot physically see anything wrong with the threads on the steel cap...it is a little more difficult to inspect the inside of the casing while lying under the car.... Perhaps I will try and take a better look this morning with a small inspection mirror up in the od cavity where the plug goes.

Cheers
Tush

 

[TR3driver]

So, what did you find?

 

[TR3TR6]

You might take the filter out and try installing the cap without the filter and see what happens. The cap might not be the problem. Good luck.

 

[M_Pied_Lourd]

Pretty bummed still.

Done pretty much everything I can and still can't get the cap back in. Yes, I did try it without the filter. I must have cross threaded it somehow.

I tried to straighten the threads out with a pick but to no avail. I can't physically see anything wrong with the threads with an inspection mirror.

I think the only recourse is to find a tap. I have given the cap to a friend of mind to take it around to some tool and die makers to confirm the size and thread type. Failing that, John at quantum has a used case but of course that will involve pulling the tranny and swapping over internals etc.

Cheers
Tush

 

[TuffTR250]

Since you most likely cannot drive the car, I recommend that you try to put the car up on real tall jack stands, or something similar, so you can get directly under the overdrive drain hole so you can get as good a look as possible at the threads in the case. When I use a mirror to look into a hard to see place it gets so distorted and backwards that I have a hard time determining what the problem may be. I'd sure try several things to determine the problem before I would replace the case. I'd probably even resort to hiring a roll back truck to take it to a place that has a lift.
Regards, Bob