351W bypass hose

[psychoSEAL]

I am in the process of adding on an old style expansion tank to my 351W. The thermostat housing on the tank does not allow me to use the bypass hose that connects to the water pump. Is it necessary to have the bypass hose? Thanks for your replies in advance.

[bobcowan]

The bypass hose keeps water circulating through the block while the thermostat is closed. It allows for a more even warm up without hot spots.

I would drill a hole on the top of the intake manifold , just behind the thermostat. Then connect that hole to the water pump. That will be your bypass hose.

[Jac Mac]

Originally Posted by psychoSEAL

I am in the process of adding on an old style expansion tank to my 351W. The thermostat housing on the tank does not allow me to use the bypass hose that connects to the water pump. Is it necessary to have the bypass hose? Thanks for your replies in advance.

Yes if you are using a Thermostat. No if you replace the thermostat with a restrictor plate with a suitably sized orifice.

Jac Mac

[Bob In Ct]

I added an expansion tank to my Windsor (pics in my gallery) and with a couple of 90 degree joints was able to keep the bypass hose.



Bob

[psychoSEAL]

Thanks again for the ideas. Bob, I didn't see any pics in your gallery that shows your set up. I am kind of slow and good pics would be a great help. I want the easiest way to go here, with the slightest modification .

[Bob In Ct]

There's an old saying, "two wrongs don't make a right, but three rights do make a left" (especially in Cleveland). Basically what I did was to take three 90 degree plastic couplers (joints) and heater hose and plumbed the bypass from the pump to the manifold. It's all buried under the tank.

Bob

[psychoSEAL]

Bob, thanks for the clarification. Did you have to modify your tank thermostat housing?

[psychoSEAL]

Bobcowan, In reply to your solution. I notice that approx. 2" behind the thermostat housing there is a 1/2" stainless bolt. Would this be an alternate sight of hooking the hose to the water pump instead of drilling? When I got this car there was a small piece of heater hose that was capped off at this point. I removed the hose and replaced it with the stainless bolt just to clean up the engine some. If this would work I could avoid drilling. Thanks, Dave

[Bob In Ct]

I put it in a couple of years ago. I think some metal had to be filed away here and there. Tony Aprile, can you add anything here?

Bob

[Sminor]

Dave, on my 428 there is a hole in the manifold about in the area you describe that is suitable for running hose to a cockpit heater/defroster. I don't know if it is the same on a small block, but if so, I don't think it will suit your purpose.
steve

[Ron61]

That location is where the heater hose was on my 351 stroker and would not work as a bypass hose. Best to use some method of connecting to the bypass outlet even if you have to go to a machine shop and have a new angled fitting machined.

Ron

[bobcowan]

Originally Posted by psychoSEAL

Bobcowan, In reply to your solution. I notice that approx. 2" behind the thermostat housing there is a 1/2" stainless bolt. Would this be an alternate sight of hooking the hose to the water pump instead of drilling?

That's normally used for a heater hose port. But you can also use it for a bypass port. Put in a 90* heater hose fitting and run it down to the water pump.

If your water pump has threaded ports, this would be a good place for AN fittings and hose.

[psychoSEAL]

When mounting the expansion tank and thermostat, could I just drill a few holes in the thermostat and just plug the water pump fitting that would lead to the thermostat housing? This would save me from making a lot of modifications.

Bob Cowan, The water pump does have threaded ports.

[bobcowan]

If you're going to be mostly street driving, and year round use, you really should have a functioning thermostat. Makes the car a lot easier to live with.

All you need to do is run a line from two existing ports, not a big deal. Might as well do it now, instead of later. I would use AN lines, but heater hose will work just as well. Probably wouldn't cost you more than $15.

[psychoSEAL]

Thanks for everyones input. Had everything figured out and the expansion tank sits about an inch to high. Can't shut the hood. Any ideas on modifying the expansion tank so it can fit. Or I may make somebody a great deal on a new 351W expansion tank.

[Sminor]

Dave,
I've got the same problem with mine. First, the carbs wouldn't fit under the hood, got a bigger hood scoop. Then the expansion tank wouldn't fit under the hood. I'm planning to have the tank mount shortened by about one inch and place rubber spacers between the frame and body. Hopefully that will cure the hood problems. I'll let you know.
steve

[psychoSEAL]

Steve, who are you going to shorten the tank? I was thinking about taking it to Galloway radiator downtown if they could even do it. I still want to use the tank if I can get it lowered as much as possible for it to fit. Maybe a sharp hack saw would do the job! The tank looked good when I put it on the car, just a little tall.

[Sminor]

Originally Posted by psychoSEAL

Steve, who are you going to shorten the tank? I was thinking about taking it to Galloway radiator downtown if they could even do it. I still want to use the tank if I can get it lowered as much as possible for it to fit. Maybe a sharp hack saw would do the job! The tank looked good when I put it on the car, just a little tall.

I'll send you a PM