Block manifold and water pump after heater delete?

[abohler1]

Been looking through tons of threads and getting different opinions and trying to fill in the blanks. Can I just plug the manifold and the water pump where each of the heater hoses used to be respectively? Or do I need to keep them connected with a short hose?
Second, I pulled the hose off the manifold and it started spewing coolant. Can I quickly plug that hole, or should I drain the radiator? Will the same happen when I pull the hose for the water pump? Thanks.

[Wrenchbender Ret]

You can plug them with pipe plugs. Its better & much less messy to drain the coolant down. You can use a sealer on the threads like RTV or Teflon tape.

[garyd1961]

If you have vortec heads or aftermarket heads you need to run a bypass. I would probably just run a short bypass hose anyway, it will help the water flow through the heads.

[hjewell2]

on a SBC gen 1 you can just plug the manifold and wtr pump the water pump has a bypass already installed in a factory piece. if you look on the bottom of the pump left hand side standing in front you will see the port where the two bolts go in .
https://www.bing.com/images/search?v...lectedIndex=66


See that extra hole on the mounting surface that's the bypass

[davepl]

Originally Posted by garyd1961

If you have vortec heads or aftermarket heads you need to run a bypass. I would probably just run a short bypass hose anyway, it will help the water flow through the heads.

Can you explain that? I've never heard that before, and can't picture why the heads would care about the heater outlet and return. On a Pontiac where one comes off the back of the head I could see it, but why would a Chevy care?

Similarly the bypass for a small block is internal to the water pump, so it's not needed for that either.

So what changed with Vortec heads (or other aftermarket heads) that makes them dependent on the heater circuit?

[garyd1961]

There is no water pump bypass on a vortec motor or motor with vortec heads or a lot of after market heads either. There is a place on the block for the bypass but it doesn't go any where , it dead ends.
Even with the water pump bypass it is still a good idea to run a bypass hose to help water flow through the heads.

[ratty69]

Originally Posted by garyd1961

There is no water pump bypass on a vortec motor or motor with vortec heads or a lot of after market heads either. There is a place on the block for the bypass but it doesn't go any where , it dead ends.

So if I understand this, the bypass hole exists in all blocks but only in pre-vortec heads. How about laying a pre-vortec gasket on a vortec head and drilling the missing hole?

Thinking about upgrading to vortecs in the future so this is good to know...

[garyd1961]

Originally Posted by ratty69

So if I understand this, the bypass hole exists in all blocks but only in pre-vortec heads. How about laying a pre-vortec gasket on a vortec head and drilling the missing hole?

Thinking about upgrading to vortecs in the future so this is good to know...

I know the hole exist in the water pump and the block but I'm not sure if it goes all the way to the head on a vortec block or not. I do know if you run a wire up in it, it bottoms out. I wouldn't just drill the hole in the heads until I found out why it was deleted in the first place. You may drill into the wrong thing or cause the head to crack. Factory vortecs are pretty thin.
Some say you can just drill a hole in your thermostat but it didn't work for me. I could drive for a little while and then my gauge would jump all over the place. I installed a bypass hose and haven't had a problem since. I even switched from a 180 thermostat with a hole drilled in it to a 195 with no hole and the gauge is still steady as a rock.