Heater-Core Bypass... How?
Thread Starter
Pro
Joined: Oct 2006
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From: Peoplez Republik (communist portland) Orygun
Heater-Core Bypass... How?
Hmmmm, so... I have been trying to make sense of the hose routing to bypass my newly discovered, slow leak heater core.
I have read & re-read my Haynes & shop book too. Scoured the Cforum for pictures or simple instructions as to "what hose goes where?"
anyone who has done this with pictures or able to send a step-by-step tutorial for a by-pass noobie would be totally helpful!!!
I just want to simply bypass the heater core until later this winter when I have more time to do the whole enchilada
I have read & re-read my Haynes & shop book too. Scoured the Cforum for pictures or simple instructions as to "what hose goes where?"
anyone who has done this with pictures or able to send a step-by-step tutorial for a by-pass noobie would be totally helpful!!!
I just want to simply bypass the heater core until later this winter when I have more time to do the whole enchilada
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Just install plugs (buy at Advance Auto and others) for the engine and water pump where the hoses are attached and get rid the engine of the hoses. It's that simple. 
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
The simplest (maybe not most elegant) means to reach your goal to bypass HC is this:
See where the small hose connects at water pump and extends to HC? check
See where the small hose connects at intake maifold and also extends to HC? check
simply connect a hose between both those two nipples: one at water pump and one at intake manifold. Yes, one hose has ID about 1/8" bigger than the other ... simply stretch one hose or squash one ... that's how it's done. If you haven't already realized it, please know that when you take the HC out of loop, it's true the heater won't have coolant flowing through it and won't work ... but ... the defroster won't work either.
edit ... jud answered before I saw his ... plugs work fine too ... but looping a hose can be done on roadside.
See where the small hose connects at water pump and extends to HC? check
See where the small hose connects at intake maifold and also extends to HC? check
simply connect a hose between both those two nipples: one at water pump and one at intake manifold. Yes, one hose has ID about 1/8" bigger than the other ... simply stretch one hose or squash one ... that's how it's done. If you haven't already realized it, please know that when you take the HC out of loop, it's true the heater won't have coolant flowing through it and won't work ... but ... the defroster won't work either.
edit ... jud answered before I saw his ... plugs work fine too ... but looping a hose can be done on roadside.
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
*EDIT* SORRY- I re-read original post! I thought the OP wanted to by-pass heater core for the usual heat in cockpit reasons. I didn't see he had a leak issue. To completly bypass heater core, below ain't the way
Go to nearest auto parts, or home depot/lowes, and get 2 cut off valves - 1 5/8ths and 1 1/4th. Also get 4 clamps (they will be at the same location).
Locate the previously identified hoses - one from water pump to heater core, other intake to heater core.
Take a knife, and cut the hoses - I cut mine at thier highest (or highest convient) location to limit the amount of coolant leak.
Insert the valves and clamp them in tightly.
The valves allow you to easily open or close the hot coolant flow - you should open the valves once every month or so to flush out the coolant that is sitting in the heater core.
Go to nearest auto parts, or home depot/lowes, and get 2 cut off valves - 1 5/8ths and 1 1/4th. Also get 4 clamps (they will be at the same location).
Locate the previously identified hoses - one from water pump to heater core, other intake to heater core.
Take a knife, and cut the hoses - I cut mine at thier highest (or highest convient) location to limit the amount of coolant leak.
Insert the valves and clamp them in tightly.
The valves allow you to easily open or close the hot coolant flow - you should open the valves once every month or so to flush out the coolant that is sitting in the heater core.
Last edited by Mashman; Jul 5, 2008 at 06:10 PM.
Thread Starter
Pro
Joined: Oct 2006
Posts: 545
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From: Peoplez Republik (communist portland) Orygun
I did it... I think?
Hey gang, thank you for the tips & ideas for the by-pass.
before I fire it up, did I do these correct?
I think that's right. Just hose the water pump to the intake, right?
Like I said, total noob on this type of repair. Never done it before.
before I fire it up, did I do these correct?
I think that's right. Just hose the water pump to the intake, right?
Like I said, total noob on this type of repair. Never done it before.
Last edited by Vette80regon; Jul 6, 2008 at 12:47 PM.
Race Director
Joined: Sep 2001
Posts: 10,560
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From: Wellington, FL
St. Jude Donor '11 thru '25
That'll work, its just kind of messy. If you are going to have the heater disconnected permanently, I would pick up some plugs, one for the heater and one for the block.
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Burning Brakes
Joined: Aug 2007
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From: Liberty Missouri
No need to loop the system
Race Director
Joined: Sep 2001
Posts: 10,560
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From: Wellington, FL
St. Jude Donor '11 thru '25
Drifting
Joined: Mar 2008
Posts: 1,900
Likes: 2
From: Nixa Missouri
I noticed in your picture of your engine, (nice looking engine) that you have a rubber hose spliced on to your discharge fuel pump fuel line.
It looks like it could be clamped on there as a protecter for the fuel line or it's a splice in the line.
If it's a rubber hose splice on the pressure line you might want to replace the steel discharge line from the fuel pump to the carb.
I can assure you you dont want to find out what happens when fuel starts to leak out underpressure and setting on a hot engine.
I am in no way trying to tell you what to do but I try to look at the safety side of thigs first. I just bought a new line for my SB & it was 24.00$ and now I can sleep at night.
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Hey there Vette8Oregon
I noticed in your picture of your engine, (nice looking engine) that you have a rubber hose spliced on to your discharge fuel pump fuel line.
It looks like it could be clamped on there as a protecter for the fuel line or it's a splice in the line.
If it's a rubber hose splice on the pressure line you might want to replace the steel discharge line from the fuel pump to the carb.
I can assure you you dont want to find out what happens when fuel starts to leak out underpressure and setting on a hot engine. I am in no way trying to tell you what to do but I try to look at the safety side of thigs first. I just bought a new line for my SB & it was 24.00$ and now I can sleep at night.
I noticed in your picture of your engine, (nice looking engine) that you have a rubber hose spliced on to your discharge fuel pump fuel line.
It looks like it could be clamped on there as a protecter for the fuel line or it's a splice in the line.
If it's a rubber hose splice on the pressure line you might want to replace the steel discharge line from the fuel pump to the carb.
I can assure you you dont want to find out what happens when fuel starts to leak out underpressure and setting on a hot engine.
I am in no way trying to tell you what to do but I try to look at the safety side of thigs first. I just bought a new line for my SB & it was 24.00$ and now I can sleep at night.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Your loop will supply lots of hot water from the manifold right back into the pump. Bypassing the radiator!
If motor temp is not a problem....................... go for it!
I was gone on a 8 day vacation and when I came back the boss decided to not send me along with the GT-40 and Bizzarini for the 11-13th races at PIR. I'm a little bumbed because the new guy gets to go.
If motor temp is not a problem....................... go for it!
I was gone on a 8 day vacation and when I came back the boss decided to not send me along with the GT-40 and Bizzarini for the 11-13th races at PIR. I'm a little bumbed because the new guy gets to go.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 98
From: Ontario
That's what I did but my A/C compressor blocks the view in the pic above. Believe me it works as an inexpensive band-aid solution until the new heater core goes in.
Thread Starter
Pro
Joined: Oct 2006
Posts: 545
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From: Peoplez Republik (communist portland) Orygun
Thanks gang!
I'll be picking up plugs from the auto store tonight!
Oh... The fuel line.
I never even thought of that before.
Is there a metal, one-piece line from the fuel pump to the carb?
Geshhh... I've never even heard of that before.
I'll be inquiring on that too.
Thanks again
I'll be picking up plugs from the auto store tonight!
Oh... The fuel line.
I never even thought of that before.Is there a metal, one-piece line from the fuel pump to the carb?
Geshhh... I've never even heard of that before.
I'll be inquiring on that too.Thanks again
Racer
Joined: Mar 2008
Posts: 428
Likes: 0
Thanks gang!
I'll be picking up plugs from the auto store tonight!
Oh... The fuel line. I never even thought of that before.
Is there a metal, one-piece line from the fuel pump to the carb?
Geshhh... I've never even heard of that before. I'll be inquiring on that too.
Thanks again
I'll be picking up plugs from the auto store tonight!
Oh... The fuel line.
I never even thought of that before.Is there a metal, one-piece line from the fuel pump to the carb?
Geshhh... I've never even heard of that before.
I'll be inquiring on that too.Thanks again
Race Director
Joined: Apr 2003
Posts: 19,348
Likes: 654
From: Tampa, Florida
It looks like you have something other than a Quadrajet? If so, any preformed fuel line you buy will need to be modified.
Regardless, what you have needs to be changed. Put some insulating material around the line where it touched the coolant hose.
Regardless, what you have needs to be changed. Put some insulating material around the line where it touched the coolant hose.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 98
From: Ontario
