ST 46 Wrist Pin Access Plug Thread Size

[Dick Pacini]

Does anyone know the thread size of the tapped hole in the rear of the cylinder casting on a ST 46?

[Bootlegger]

 Dick, I sent ya' a P M  good luck...

[EddyR]

I have seen many that the bolt is missing and they seem to run normal.Must be that they don't leak with it missing.
Ed

[Andrew Tinsley]

I don't have an ST46, but I thought thethreaded hole had something to do with pushing out the wrist pin. I may well be wrong on this and goodness knows where the pin would go.
  perhaps someone would tell me if I am right or not!

Regards,

Andrew.

[Bill Little]

I don't have an ST46, but I thought thethreaded hole had something to do with pushing out the wrist pin. I may well be wrong on this and goodness knows where the pin would go.
  perhaps someone would tell me if I am right or not!

Regards,

Andrew.

Hi Andrew,

The hole is for the wrist pin removal, but you do not "push" it out, you PULL it out.  I have used a needle from the ST NVA to thread in the hole in the wrist pin.

Bill

[Andrew Tinsley]

Thanks Bill!
It all makes sense now. Amazing how you can go for years with the wrong idea!

Regards,

Andrew.

[EddyR]

If you see a ST/40-46 with a hole in the front directly opposite the rear hole then some one has drilled it to push the pin out. If the pin is frozen to the piston this method will work. A 1/8" hole will work so a drift punch will fin in. Be careful to not pull the sleeve out all the way as it is needed to support the piston. If they leak,tap it and put in a bolt and grind it flat inside or just JBWeld it.
Ed