TR2/3/3A TR3A Vacuum Advance Suction Tube Tool Needed

[Tinkerman]

This is really an add on to an older thread I had started. In working with Dave at TRF I found that the suction tube I needed was one with a female fitting at the distributor end and a male fitting at the carb end. I had one but was having troubles with it, so I bought a new one from TRF, so far so good. I took the carbs off and could see that the treads were messed up at the at the start of the opening. I thought I might be able to clear them with a new fitting. WRONG! My buddy at ace and I determined that the male fitting is a 9/32 X 24 TPI fitting. Easily cleared with the proper hand tap, if I had one!

question 1. is are we correct on the 9/32 X 24 size?

Question 2. Does anyone have a tap 9/32 X 24 tap that I can buy or borrow? Or where can I go to get one.

I have not had much luck on the net. Fastenal nor Grainger could help me out. Local auto parts stores can't help either.
I will keep trolling the net but if any one can help me out here I would appreciate it.

Thanks, Tinkerman

 

[TR4nut]

Dick-

Enco has them at least: 9/32-24 tap

But let me check first on some taps I have - I inherited a small collection with various weird sizes - I just might have that one.

Randy

 

[Tinkerman]

Thanks Randy, Let me know. I am just a tad frustrated over this one!

Cheers, Dick

 

[TR4nut]

Sorry Dick-

Just checked, that's a weird size, I don't have it in my stash.

Randy

 

[MGTF1250Dave]

Aloha Dick,

I recently fabricated a vacuum line for my TR3. I used 1/8 inch compression nuts and olives and 1/8 inch copper tubing. The thread size for the compression nut is 5/16 - 24 UNF. The nuts went on the carburetor and vacuum advance without a problem.

My car has a union that is threads into the front carb, so I have a used compression nuts on both ends of the tube.

 

[Tinkerman]

On mine Dave, the fitting goes directly into the carb. I could get a union from TRF, but I still have to clean up the threads on the carb.

Thanks for the info.

Tinkerman

 

[MGTF1250Dave]

Aloha Dick,

I don't know how the vacuum line was originally set up on my car, but some where during it's long life the attachment hole on the carb was butchered. Probably trying to insert something that didn't fit or cross threaded. The threads in the carb are almost nonexistent. When I had the carbs rebuilt recently, it was suggested that I just use epoxy the union in place. Cleaning the carb body freed the union and it had been held in place some stick substance. I used epoxy and the lash up is working fine and now I can use 1/8 compression fitting on the line.

Perhaps mine originally had a male fitting on the line also.

 

[Tinkerman]

I imagine JB Weld would do the job. Thanks for the tip Dave. I have the correct tap on it's way here from ENCO. Nice to know that there is an option though in case the tap doesn't do the job.

Dick

 

[Tinkerman]

Final closure on this thread. The hand tap came in yesterday, so I tried it out today. Worked like a champ, no more problem with the thread in the SU body. Thanks to all who helped!

Cheers, Tinkerman