Water Pump Question
Thread Starter
Racer
Joined: Jan 2005
Posts: 364
Likes: 0
From: Winder GA.
Water Pump Question
I recently replaced the water pump on my '65 327 with a polished aluminum one. It has an outlet on the top of the main housing that my cast iron one did not have. I see also that there is a plug on the driver's side in the front of the intake manifold. I have seen reference to this being a "bypass"? Bypass what if they are plumbed together? Is there any advantage to hooking them up? Everthing seemed fine before when there was no extra outlet in the previous water pump. Any info will be much appreciated.
Melting Slicks
Joined: Aug 2004
Posts: 3,078
Likes: 101
From: Riverhead New York
I recently replaced the water pump on my '65 327 with a polished aluminum one. It has an outlet on the top of the main housing that my cast iron one did not have. I see also that there is a plug on the driver's side in the front of the intake manifold. I have seen reference to this being a "bypass"? Bypass what if they are plumbed together? Is there any advantage to hooking them up? Everthing seemed fine before when there was no extra outlet in the previous water pump. Any info will be much appreciated.
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
The 327/350 and 327/365 used the same aluminum intake manifold, which had a bypass fitting at the front, with a hose to the bypass fitting on top of the water pump. The 250hp and 300hp used an iron intake manifold with no bypass fitting, and a different water pump that also had no bypass fitting. 
Thread Starter
Racer
Joined: Jan 2005
Posts: 364
Likes: 0
From: Winder GA.
Thanks guys. The intake is an original aluminum one which the numbers say was for a 365 hp engine. It has an outlet plugged as I said. But, part of the question is about whether there is an advantage or even a useful purpose in hooking that outlet to the one on the new polished aluminum hi-output water pump? What was that about anyhow?
Any thoughts? Opinions? 
Any thoughts? Opinions?
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
The purpose for it is to prevent the water pump from cavitating the coolant at high rpm by allowing water to flow through the "by-pass" instead of simply cavitating because of blockage by the thermostat.
Now, go lay down.
Thread Starter
Racer
Joined: Jan 2005
Posts: 364
Likes: 0
From: Winder GA.
MikeM
Thank you sir. I had thought perhaps it bypassed warmer (hot) water into the intake mainfold for soome odd reason that I did not understand. Since I only use the car for mild street driving, I suspect hooking the bypass up is of no consequence either way.
And laying down is always something I can excell at!
Thank you sir. I had thought perhaps it bypassed warmer (hot) water into the intake mainfold for soome odd reason that I did not understand. Since I only use the car for mild street driving, I suspect hooking the bypass up is of no consequence either way.
And laying down is always something I can excell at!
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From: Washington Michigan