Hi all,

Does anyone know what thread for the hose adapter is used on a crossflow water pump. It's the smaller hose that runs to the heater matrix, or in my case straight to the inlet manifold.

I assume its 5/8 NPT as it's near 17mm but it doesn't poke through my 5/8 bolt size checker thing and other sites suggest its 3/8 which is way too small.

My current adapter is too small on the hose side, which I'm trying to match with the inlet manifold (about 13mm).

Thanks!
Jon

I may have a straight fitting , can check tomorrow i

Imperial pipe thread sizes refer to the internal bore of the pipe it is intended to be cut on, not the outer threaded diameter, 3/8 npt sounds about right for 17mm od.
You may find some brass hose tails that will work from plumbing suppliers, the angled ones are dear from burtons and not available new anywhere else.

Dave

Ah that makes sense and explains the confusion on my part.

Anyone know if I can just blank both these off as I don't have a heater, or does water need to flow through the inlet manifold?

They should be connected as you need bypass flow to help the coolant warm up evenly and prevent hot spots.

Dave

Cool, thanks.

Jon

The top of the Water pump vertical, and the inlet manifold are joined together, with 16/17 o/d mm hose, both of the threads should be the same,
and are the same as gas/plumbing fittings,
i cant remember which,

If you dont connect them up, with a downdraft carb, you will get carb icing, as the fuel will be to cold

steve

it will be a bsp size.

Not sure now, thinking about it. Apologies for adding confusion.

honey,you have u2u

Big thanks to Rusty Nuts (Mel) for sending me out the right size part and being too kind to accept anything for it!

Thanks!
Jon