I wanted to start of by saying I got my pictures posted in the General forum under (New to the forum check out my Vette) check them out. Now I can not cut the heater off. I still feel heat inside the Vette. I was thinking it was the heater control valve. It is the original one. Should I go with a new one if so what is the best? Or just put a turn valve in its place. Let me know what you all have done and think.
Thanks

 

Are you sure that it is from the heater and not just heat coming into the cabin from the engine bay?

 

Thats a good question and I'm not sure. It just seems hot in there. How can I find out for sure?

 

I just put a 3/4" PEX ball valve in mine. I never want any heat coming inside anyway unless I am out and it looks like it might rain. Then I'll crack it for the defrost.

 

Do you have a picture of the 3/4" PEX ball valve installed? How does it look? Where did you get it? Just remove the control valve and did it fit in its place?
Thanks

 

I installed my ball valve right back of the A/C compressor. I carry the handle in my storage compartment so that I can open it up if I wish. I still have the original valve there as well.

 

That is a really good idea! Where did you get your valve?

 

I just went to the plumbing dept of a local hardware store and picked up the stainless valve and the two fittings. These valves are readily available.

 

If you still get heat it could be one a number of things.

The lever on your switch "hot to cold" has a bicycle type cable that runs to the heater core box...it is suppose to close a door in the core box that blocks off the heat. It may not be closing the door. You need to remove the passengerside dash pad to see the core box.

Other possibility is the valve on the hose towards the passengerside in the engine compartment...its suppose to stop the flow of hot water to the heater core.

It could also be the switch its self malfunctioning.

Jim

 

If you'd figured out that you have a damaged heater core, replace it immediately. Coolant leaks are one of the symptoms. My dad once had a malfunctioning Mercedes heater core, he thought it wouldn't affect much of his car's performance... but it did!

 

Hey binnie77, Tell me more about that 70 Cuda.I had a 71 with 383/4 speed.It was a dark green with a white interior.When I got it it was built up with a new cam and heads,intake,headers.Had a real nice lope to it.Just the sound of that cam scared off other cars.They wouldn't race me.Come to think of it it had a reputation in the small north east Gerogia town I lived in.

 

I had a similar situation when we first purchased our Vette... here is what I tried and found out about what can cause this...

* you are correct in that the control valve can impact this...mine had a vacume line attached at the top which was controlled by a switch behind the glove box (more about this below)....make sure the vacume line is attached well and is getting good vacume. Mine was not connected well.
* someone noted above that the cold - hot lever is attached to a door lever behind the glove box. In addition, the cable has an in-line adjuster that can be turned to lengthen or shorten the cable caseing...this helps with adjusting the movement at the door lever... In addition my door lever when moved to the fullly Cold position - makes contact with a vacume switch mounted next to the door lever (again, behind the glove box). It was this vacume switch that controls the vacume at my control valve. I found that the door level would not move enough to engage the vacume switch even with the cable fully adjusted....ended up fixing the situation by building up the door level surface so that it would make contact with the switch and operate properly.

All has worked well since...2 years and counting...

Another thought... to verify if the heat is coming from your HVAC system or engine/trans/exhaust... just move your selector to vent...if it's HVAC then warm air will shift to the upper vents.


Good Luck... Ed

 

Here's a picture of the PEX valve I am using. I installed it in place of the stock vacuum valve, but you could put it anywhere you want in the heater core loop. As you can see the ends are already barbed, you you dont need to buy additional fittings or nipples, just clamp it on.