Bypass Heater Core
Thread Starter
Racer
Joined: Jul 2013
Posts: 423
Likes: 6
Bypass Heater Core
I am wanting to bypass the heater core in my 78. would it be ok to connect the 2 hoses that go to the water shut off valve ? and what size connector would I need ?? Thanks for your help..
Le Mans Master
Joined: Apr 2008
Posts: 9,425
Likes: 239
From: Powassan ON
IMO if you connect them hot water will still circulate through the core.
Put a brass or stainless steel 1/4 turn ball valve inline.
Your hoses may have been changed at some point. Mine is 5/8"id if i recall.
If its an A/C car, for some reason I think the hoses are different sizes. Somebody with vastly more knowledge will chime in I'm sure.
Serach "heater shut off" here. LOTS of threads already.
dodosmike
Put a brass or stainless steel 1/4 turn ball valve inline.
Your hoses may have been changed at some point. Mine is 5/8"id if i recall.
If its an A/C car, for some reason I think the hoses are different sizes. Somebody with vastly more knowledge will chime in I'm sure.
Serach "heater shut off" here. LOTS of threads already.
dodosmike
Racer
Joined: Dec 2009
Posts: 415
Likes: 10
From: Richmond Va
While I was breaking in my engine and doing general mach up, I just ran a loop from the water pump to the intake. The two inlets are different sizes, but I had zero leaks just using regular hose clamps on the smaller port.
5/8 and 3/4 is correct. Just bought new ones last week.
5/8 and 3/4 is correct. Just bought new ones last week.
Last edited by MalibuVLX; Aug 23, 2013 at 09:27 PM. Reason: more info
Le Mans Master
Joined: Nov 2006
Posts: 7,215
Likes: 1
From: Orlando FL
that worksor loop from pump to intake
or just pipe plug pump and intake
any of these work
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Drifting
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From: Central NJ
Melting Slicks
Joined: Sep 2011
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From: Peoria Arizona
Pro
Joined: Oct 2009
Posts: 523
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From: Calgary Alberta
It looks much better and don't have the extra hoses in the engine compartment that are not doing anything.
Plus it ensures there is no unwanted heat coming in from the heater core
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
My heater core was leaking so I disconnected the hoses from the engine and core and put plugs in the intake and water pump.
It looks much better and don't have the extra hoses in the engine compartment that are not doing anything.
Plus it ensures there is no unwanted heat coming in from the heater core
It looks much better and don't have the extra hoses in the engine compartment that are not doing anything.
Plus it ensures there is no unwanted heat coming in from the heater core
Like others have said, use plugs at the intake and water pump. Eliminate the hoses completely and certainly don't add a goofy looking bypass hose.
Burning Brakes
Joined: Aug 2002
Posts: 1,190
Likes: 56
From: Milan Indiana
bypass heater core
I see how the bypass works on your later C3's. Where do you find the plugs for the intake and water pump and in my 68,there is a small tank on the fender where hoses go. The tank hoses have been 'looped' as the hoses are off the heater core ends. Little help Please Thanks
Le Mans Master
Joined: Oct 2006
Posts: 8,940
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From: El Cajon California
Melting Slicks
Joined: Sep 2011
Posts: 3,372
Likes: 215
From: Peoria Arizona
The fittings in the water water pump and intake are standard pipe thread. Depending on what type of plug you want, you can pick them up at a hardware store, or if you want something nicer, try a local parts place or Summit.
In my aluminum intake, I used the brass version. The plugs in the water pump are steel. All of them came from a local hardware store. You can see most of them in this photo...
Adam
In my aluminum intake, I used the brass version. The plugs in the water pump are steel. All of them came from a local hardware store. You can see most of them in this photo...
Adam
Last edited by AdamMeh; Apr 21, 2014 at 01:07 PM.
Drifting
Joined: Jul 2008
Posts: 1,873
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From: Sonora CA
Might work ok if you live in Alaska, but otherwise............Don't do it.
Le Mans Master
Joined: May 2002
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From: Lebanon Township New Jersey
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Wrong
Aahhhh...sorry, that is not correct. The heater core is not a radiator.