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Old 10-20-2019, 08:01 AM   #1
Gregski
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Water Pump Heater Core Bypass

forgive me for asking, I did do a search but could not see the specific info I need, I have a 5.7L Vortec engine in my '54 (don't ask, came that way, lol) and I want to run a heater core delete so I am not 100% sure how to hook up the two horns on this Vortecian water pump to run the bypass hose

1. Do I just connect the horns together?

2. Currently I am running the passenger side horn (aka nipple outlet/inlet?) to the outlet/inlet port on the intake manifold, and I am just capping the horn on the driver side, is that right?

3. Or do I have that backwards and I need to run the outlet/inlet on the intake manifold to the driver side horn on the water pump and just cap the passenger side water pump horn?

I think I read somewhere that the driver side water pump horn connects to the heater core but I don't know if that's coming or going, ha ha, and I have no idea where the passenger side water pump horn goes to, I guess I should have paid more attention when I had my '97 Tahoe back in the day.

I hope I didn't confuse all you all, help is greatly appreciated.
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Old 10-22-2019, 05:07 PM   #2
speedygonzales
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Re: Water Pump Heater Core Bypass

You're making this way to complicated. If you want to bypass the heater core, then just remove the 2 lines from the heater core and connect them together. https://www.oreillyauto.com/detail/b...onnector&pos=5
Done.

FYI the driver side nipple (on the water pump) goes to the heater core. The one on the passenger side as you mentioned, goes up to the intake manifold.

The heater core returns to the manifold.

My thinking is the since the water pump is circulating to the heater core constantly, it probably should not be blocked off from doing so. With that in mind, simply making a loop could never hurt. Where as not doing so is a question. So if you are in a vehicle that does not have a heater core, Then the nipple on the driver side of the pump will hook up to the passenger side of the intake manifold.
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Old 10-23-2019, 08:06 AM   #3
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Re: Water Pump Heater Core Bypass

Thanks for the reply.

Quote:
Originally Posted by speedygonzales View Post
The one on the passenger side as you mentioned, goes up to the intake manifold.
Ok, yes I got that hooked up already.

Quote:
Originally Posted by speedygonzales View Post
... the nipple on the driver side of the pump will hook up to the passenger side of the intake manifold.
So basically both water pump nipples go to the intake manifold? That sounds counter productive, as one will be pumping in and the other working against it pumping out. Or are you saying block off the passenger side nipple on the water pump and loop the drive side one to the intake? So Option 3.

Please keep in mind I am not running the stock intake manifold but an Edelbrock Performer, for what it's worth.

I don't know how many times I refer to this diagram, not specifically for the 5.7L Vortec but I think it gives us the general idea of which side of the water pump the little BYPASS HOSE goes on.
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Last edited by Gregski; 10-23-2019 at 08:14 AM.
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Old 10-23-2019, 08:49 AM   #4
geezer#99
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Re: Water Pump Heater Core Bypass

The important thing to remember in the coolant flow is that any port on your water pump is an inlet (suction)and not an outlet (pressure).
Your handy diagram shows that.
Since you already have a bypass from the intake to the carb you don’t really need another bypass that is routed thru the heater core.
You only need a small flow to keep circulation going to prevent hot pockets forming in the heads.
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Old 10-23-2019, 09:08 AM   #5
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Re: Water Pump Heater Core Bypass

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Originally Posted by geezer#99 View Post
The important thing to remember in the coolant flow is that any port on your water pump is an inlet (suction)and not an outlet (pressure).
Your handy diagram shows that.
Since you already have a bypass from the intake to the carb you donít really need another bypass that is routed thru the heater core.
You only need a small flow to keep circulation going to prevent hot pockets forming in the heads.
ah snap, great observation, and a lesson learned for me! Wait why call it a pump then, shouldn't it be called a Suck?
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Old 10-23-2019, 09:14 AM   #6
geezer#99
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Re: Water Pump Heater Core Bypass

It pumps coolant thru the motor of course. So it’s a pump.
The only problem I see with that style pump with the hose barbs is you’d need a hose or cap on the unused barb to seal it off. Unless of course the barb unscrews from the pump then a plug could be used.
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Old 10-24-2019, 10:22 AM   #7
Gregski
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Re: Water Pump Heater Core Bypass

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Originally Posted by geezer#99 View Post
It pumps coolant thru the motor of course. So itís a pump.
The only problem I see with that style pump with the hose barbs is youíd need a hose or cap on the unused barb to seal it off. Unless of course the barb unscrews from the pump then a plug could be used.
here's a pic of how I am pulling it off
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Old 10-31-2019, 07:17 PM   #8
hatzie
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Re: Water Pump Heater Core Bypass

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Originally Posted by Gregski View Post
here's a pic of how I am pulling it off
That's the right way to do it.
You still need the flow from the intake to the water pump in both locations so you don't get hot spots.

Is the heater core leaking?
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Old 11-02-2019, 11:52 AM   #9
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Re: Water Pump Heater Core Bypass

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Is the heater core leaking?
Thanks for the reply hatzie, I am not sure if the heater core is ok or not, I had a million things to worry about in building this rig, so I eliminated as many optional components as possible for Phase I, I hope you understand and follow my logic. I am in California so I like to pretend heater cores are optional until I really really need em, ha ha
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