Some progress and a question

[John Nickell]

Got a chance to get home and help my dad out with the engine/transmission install on his ’48 Dodge. After too much time getting a re-wire job and a coat of paint in the engine bay it was finally time for the engine to go back in. The engine and transmission went back in without too much trouble. I have a couple of before and after pictures.

The question I have is about the internal/external bypass aspect of the cooling system. I believe the new engine is setup for internal bypass. The block has a hole in the correct place as well as the water pump and the head has a small hump in it that appears to go over the hole on the block. Is the only thing we need to change the piece circled in the 5th picture, that was used for the external bypass?

[greg g]

the water pump is set up for external bypass however your engine and hose outlet are set up for internal bypass. The plate on the back of the pump needs to have the hole put in it to match up to the one on the front of the block. The outlet that faces toward the firewall will need to be plugged of but it will work. If you want to run it with an external bypass you need to source the different thermostat housing and outlet.

The pic is one I have savd of a cut out engine that shows the external bypass set up. You can see where the short piece of hose complets the flow path between the stat housing and the pump.

[Normspeed]

Hi John, I think you got it. If that water pump is like the last one I bought, you can just close off that area with a pipe plug, unless you want to run a heater.

[John Nickell]

Thanks for the help guys.

Greg I think the water pump has the hole you are referring to. I re-posted the picture with the hole I think you are talking about circled.

[greg g]

I may be way off base as it has been a long time since I had mine off, but I think you need to open up the backing plate to match the large hole in the block. Wish I could be sure but, I know the manual shows a gasket with that hole punched out.

[John Nickell]

I see what you're talking about. I believe the gasket did have a hole in it for the large hole but no hole in the backing plate. Maybe someone else will chime in with a definitive answer. Thanks again for your help.

[Merle Coggins]

You do have a hole in the pump plate that will match up the the large hole in the block. It's just a bit smaller. That's all you need. You have an internal bypass water pump. You can remove you other neck assembly and plug it as shown in one of the posts, or put a different nipple in there for your heater.

Merle