Thread size inquiry

[Fairlady5150]

Hello all. Wondering if anybody knows the thread size for the block drain valve on an early / 3-main 1600 block? Also looking for thread sizes to plug the coolant line inlet and outlet on the intake manifold.

[keith0alan]

I don't remember the exact sizes but they are BSPT and not common hardware store pipe threads. Check with your local hydraulic shop rather than plumbing store.

[Solex68]

1/8 X 28 BSPT

[david premo]

I think it’s 1/4 BSPT actually. The 1/8 BSPT are the ones along the oil gallery at the front of the 1600 and 2000. BSPT not only has a different thread count, the shape of the thread is different as well. As it’s a 1500 I’m not 100% sure, it could even be 3/8 BSPT.
Dave

[Fairlady5150]

Thanks all!