TR2/3/3A Fuel Shutoff Valve

[ckeithjordan]

John and Others,

I still haven't fitted your machined part to the shutoff valve on my car, which is original (it's at the body shop for metal work and a repaint). I did try, however, to fit your part on a valve from Moss. Here's what I found:

Moss part
Shaft measures .447 inch
Cork measures .449 inch
Chamber measures .493 (I guess this allows for swelling of the cork piece?)

Your machined part
Piston .508 inch
Over O rings .532

As you can see, your part as machined won't fit the chamber of a Moss part. Just FYI.

 

[CJD]

Cork measures .449 inch
Chamber measures .493 (I guess this allows for swelling of the cork piece?)

More the .044" is allowance for ample leakage LOL. Whereas the cork swells when new, after a year it begins to shrink again. Your knowing you have a repro valve may explain the difference in cylinder sizes. I have been told by 2 they fit as I sent, 2 that they needed only some minor opening with a file, and 2, like you, where they aren't even close. I am thinking the repros are the difference.

 

[ckeithjordan]

Let me revise some of the numbers on the Moss repro version:

Cylinder (plunger) .448
Cork .492-.493
Inside chamber .491

Much closer tolerances than I described earlier, but still smaller than machined piece. As I mentioned earlier, I have not measured, nor tried to install in my original-with-car valve, as it is at the body shop. Once I get the car back, I'll take it apart and see.

I think you're probably right, the repros are different measurements compare to the originals.

 

[James A Martin]

I must have a repro piece also.
I think my address is in your message file but PM me if you need it.

1962 Triumph TR3B
TCF2326L