1989 C4 Heater Control Valve ?

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Dec 16, 2017 | 11:20 PM

1982Stingray

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1989 C4 Heater Control Valve ?

On a 1989 Corvette,
1) is there a heater control valve?
or
does coolant pass through it constantly when running?

2) If constant, has anyone in warmer climates installed a Heater Control Valve? or some mean to bypass the heater core for summer months.

3) Can heater hose be removed and holes plugged or is circulation between the 2 ports necessary?

Thanks

Dec 17, 2017 | 10:18 AM

belairbrian

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From: Central Alabama

89 has a constant flow.

You can bypass the core. Do it by removing the hoses at the core and connecting them to each other. That will maintain the circulation path which includes the engine coolant bypass path.

Dec 17, 2017 | 10:25 AM

WVZR-1

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Quote:

Originally Posted by belairbrian

This procedure creates one potential possible issue. If you have difficulties removing the hoses from the heater core tubes you can very likely break the tubes from the core. You won't know until you go to redo the original plumbing and now you've got a heater core replacement looking you in the face. Even if you remove with no damage when you redo it you can create the same heater core tube issues.

OP - Leave as is and do a proper repair. Do you actually have an issue or just curious? Cut hoses forward of the core but behind the vent to intake maybe. I've no idea if there's room to accomplish that or not. A valve would require talent.

Last edited by WVZR-1; Dec 17, 2017 at 10:32 AM.

Dec 17, 2017 | 10:38 AM

s carter

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From: New Port Richey FL

Living in FL with a 93 Six Speed I have not really had a problem with a heater core giving unwanted Heat, Coming thru Floors yes? Up the Center Console thru Shiftier YES.

To add a Valve possible "Yes" In fact in the past few weeks someone put a Forum in on the Success they had putting a other vehicle style valve in their car. the one thing that I can think of is how to control the valve other than having a Plugged Vac. Hose that you put on when needed, or running a "T" from the Heater Bend Door if the door Command would work for the Valve Function
https://www.corvetteforum.com/forums...ter-valve.html

Last edited by s carter; Dec 17, 2017 at 10:54 AM.

Dec 17, 2017 | 12:29 PM

1982Stingray

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Car has 49k miles and cooling system in good shape, but since I have interior out to put added insulation and stereo upgrade, i replaced old heater core since most of that labor was already done, old core looked fine and was Brass the only new ones i could find are Aluminum, and i replaced all cooling system hoses.

I noticed there was no heater control valve (but saw one on a c4 before, maybe 1984), and thought this must be why it feels warmer than it should in summer.

Yes a lot of heat comes out from console, i take it that is normal, but is it from the transmission and not heater?

I know from my other cars, even those designed with constant heat circulation that the AC blows cooler where the heater core is not being heated.

Dec 20, 2017 | 03:08 PM

Hot Rod Roy

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From: Mission Viejo CA

Quote:

Originally Posted by s carter

To add a Valve possible "Yes" In fact in the past few weeks someone put a Forum in on the Success they had putting a other vehicle style valve in their car. the one thing that I can think of is how to control the valve.
https://www.corvetteforum.com/forums...ter-valve.html

If you don't have a "switched" vacuum source to control the heater valve (like my '84 does), you could create one by using a vacuum solenoid, like the one for your EGR valve, which could be controlled by a toggle switch in the cockpit. Connect the vacuum solenoid between a manifold vacuum source and the heater valve.