Heater Core Bypass?

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Skyman
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Heater Core Bypass?

Post by Skyman »

As some may know from a previous post, my heater core has gone south and has leaked all over my passenger flooring. While I take this out, and figure out if I can repair this one, or get another, is there a quick heater core bypass that anyone has done? I was just thinking of getting a length of tubing, and make a loop.

This is now the second heater core I have tried. Is there a good aftermarket one I could modify? I really don't want to go down this path again.

Thanks!
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EScanlon

Re: Heater Core Bypass?

Post by EScanlon »

The car's plumbing has one built in. What I'm not completely sure is if the heater core is then completely capped off when you use the valve that is on the car.

Look aft of the rear carburator and you should see a long teardrop shaped (somewhat) handle connected to the tubing that's attached both to the Carb Heat Shield and the Intake Manifold. If it's pointing straight up, it allows coolant to flow to the heater core, if it's pointing to the carbs, it recirculates it.

Hope someone else can chime in if the return from the heater core is then plugged or if it needs to be capped.

E
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Re: Heater Core Bypass?

Post by jamesw »

Just disconnect the long heater hose and loop it back on itself and connect it to either the water pump or the water tube on the manifold - I can't remember which at the moment. Works like a charm. Don't trust the heater valve not to leak...
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Re: Heater Core Bypass?

Post by SLOroadster »

The easy way is to plug the hole in the waterpump, and the one off the back of the intake. Ziptie the hoses to something so they don't rub something hot and melt. The intake and the waterpump are both NPT as far as I know.

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Re: Heater Core Bypass?

Post by K1200 GT »

When you take the core out you could run a hose through the compartment. Back out and connect them in there rightful places. Depends if you want heat that you cant control. You would then have some heat for winter driving inside. Until you get your core repaired.

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Re: Heater Core Bypass?

Post by Linda »

What is it costing for a heater recore these days?
TIA

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Re: Heater Core Bypass?

Post by K1200 GT »

They can be repaired like a radiator if the tanks are metal. And Im sure they are cause of the age of the cars. The cores can be replaced just like a radiator. made to look and function like new. I would say $ 100-200. its an art these days. :D

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Re: Heater Core Bypass?

Post by Linda »

They can be repaired like a radiator if the tanks are metal. And Im sure they are cause of the age of the cars. The cores can be replaced just like a radiator. made to look and function like new. I would say $ 100-200. its an art these days.
Rich

If I need one I'll be looking for a less artistic plastic one. Anyone found a swap?

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Re: Heater Core Bypass?

Post by K1200 GT »

Linda,

I have never seen a plastic heater core. Thats not to say they dont make one. Why plastic?
You could take the measurements of your old one with the in let and out lets to. Go to Napa use there books or internet and pick one out that is real close. If you have to you can take to a radiator shop to have different angles of pipping sweated on to make the angles you need. I know thats a lot of work.
But can be done.

Rich
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Re: Heater Core Bypass?

Post by spyder »

Mine sprung a leak so I took it to a highly regarded radiator shop here in San Antonio and they charged $175. I thought price was outrageous but since it is a non standard item I suspect it was a labor issue.
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Re: Heater Core Bypass?

Post by Linda »

The current Rock Auto newsletter has a blurb about plastic radiators:
http://www.rockauto.com/Newsletter/index.html" onclick="window.open(this.href);return false;

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Re: Heater Core Bypass?

Post by K1200 GT »

Plastics of sorts have come a long way over the past 20-30 yrs. I see they only use the plastics on the tanks...they havent figured out how to get the fins and tubing to keep things kool with plastic yet. i bought a plastic type radiator for my 86 Toyota Cressida. Looked for an original but was about $100 more. They are using plastic tubing in houses around here now... under the houses...say it will not burst like brass tubing and can expand some. Car manufactures are always finding ways to cut down on weight. There will be a plastic engine with pistons some day. I wont be around to see it....maybe. :roll:

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2000 Miata Special Edition 6 spd/LSD
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1999 Dodge 3/4 4x4
1986 Toyota Cressida
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1992 BMW R100RT (1000cc)
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Re: Heater Core Bypass?

Post by notoptoy »

Except for the Pistons, it's been done!
http://en.wikipedia.org/wiki/Plastic_automotive_engine" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

http://books.google.com/books?id=FzCnbu ... ne&f=false" onclick="window.open(this.href);return false;
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

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K1200 GT
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Re: Heater Core Bypass?

Post by K1200 GT »

Thanks Tom,
I didnt know...who wouldathunk. Just didnt last long...in production.

Rich
Life is good...but I want more
If I cant fix it, It aint broke
Rich

2000 Miata Special Edition 6 spd/LSD
1970 SPL 311
1999 Dodge 3/4 4x4
1986 Toyota Cressida
2003 BMW K1200GT (1200 cc)
1992 BMW R100RT (1000cc)
1969 BMW R69S (600cc)
1997 BMW 328I
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Skyman
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Re: Heater Core Bypass?

Post by Skyman »

I spent a couple of hours removing the heater core today. What a PITA that was. It was sure a lot easier putting it in when the dash and everything wasn't there. I guess now I need to take it in and see if it can be fixed. I'm still concerned about putting another one back in and having this happen a third time. Has anyone found a aftermarket core?
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