heater delete

[Frank K.]

I want to delete my heater for the summer. What is the direction I should go in so I can install it back to heat. 77 non air car.

[Michael W.]

Re: heater delete

Install a shutoff valve in one of the two coolants lines connected to the heater core.

[Frank K.]

Re: heater delete

Before or after the hot water valve? Where do I get this valve?

[Michael W.]

Re: heater delete

If there's already a hot water valve installed and it works, you're all set. Or maybe I don't quite understand your goal (?)

All that's required is something to stop the flow of coolant through the heater core.

[Tom B.]

Re: heater delete

There is no hot water valve on a non a/c car. You can install one in the inlet line to heater core. There are aftermarket manual valves.

[Frank K.]

Re: heater delete

It is a vacuum operated hot water shut off valve for the heater

[Larry M.]

Re: heater delete

The later C3 hot water valves were fail open valves (no vacuum to valve = heat). So first make certain this valve works and will shut-off water flow when the car is started and vacuum is available. You could even bypass the heater controls and simply connect a small vacuum hose directly to the valve directly to always keep it closed when the car is running. Sometimes in these older cars the heater control plastic control block leaks and will not allow a vacuum to be pulled on this valve.

If that works as designed, you should be all set. I guess you could also install one or two manual shut-off valves on the inlet and outlet heater lines if you really want to, but I think this is unnecessary.

You could also replace the valve you have with a C2 type shutoff valve that is closed unless vacuum is applied, and simply not connect the vacuum hose to it. Just plug the vacuum hose.

Larry

[Richard L.]

Re: heater delete

Mike is correct...

You stated that you have a non-A/C car so it won't (or shouldn't) have a vacuum-controlled hot water shut-off valve... Install a manual 2-way ball valve (rated for correct temperature) in the heater hose line that does not go to the radiator expansion tank (if your '77 has one installed)...

This will stop the flow of water through your heater core causing the undesired radiant heat transfer...

Not at all NCRS correct, however, but it will solve your problem...

[Frank K.]

Re: heater delete

I have a valve! I saw the identical car to mine in new Hampshire this week end with the valve. I also see the valve listed in the Mid America assembly manual. I also saw a shut off valve installed to shut the heat off completely I know GM went with a different control system after the 1976 production. I never had a problem with heat in my non air 1975 car. I believe non air 77 corvettes had a heat problem in the summer. Remember the fan runs at low speed all times. There is no motor heat entering the cabin its exiting the lower floor duct with the controls in the off position.