Thread size

Can anybody tell me the thread size/type for the two holes beneath the thermostat housing. The ones for the heater valve and the temp’ gauge sender.

I want to run a tap down them to clean the threads

Thanks Mike :smiley:

Not off the top of my head - but they are taper BSP thread so don’t go running a tap right through. Come to think of it, I’m not sure that they are both the same thread, either.

That wasn’t much use, was it? :blush:

Cheers,
Pete.

The forwardmost hole for the temperature bulb fitting is a 3/8-19 BSPP (parallel).

The rearmost hole for the heater valve is 3/8-19 BSPT (taper).

Thanks Scott and Pete,

I have a parallel and am sure the father-in-law will have the taper (Retired Plumber).

Mike

:smiley: