Isolate heater core in summer
 

Anyone use valves in their heater hoses to manually isolate the heater core in summer? Curious if it makes a worthwhile difference. 65 GTO, non-ac car.

I was wondering that myself as the 64 Corvette I am working on they used them on both lines -as well as made a spaghetti bowl of heater and A/C hoses that is butt ugly!

Why for summertime do you not just use a union to jump it out instead of spending far more money on a control valve?

And yes it makes a difference as that’s why ac cars have control valves, a ton of difference , no.

i meant something like this:

https://www.amazon.com/Joywayus-Auto...Y2hfYXRm&psc=1

Nope never done that and we drive the cars in 100+ temps. Plus it's butt ugly. I'd gasp if I opened my hood to that and then quickly close it before anyone else saw that mess :D

the day that valve is the ugliest thing under my hood, i will kneel down and thank the heavens.

At 20 bucks this is a far cheaper and far less unsightly solution.

If you jack up the ass end of the car 8” when installing these you will not even spill any coolant.

I think one gets more heat through the floor boards from the headers than hot water circulating through the heater core. Plus running the heater on high can help cool the engine down if you get caught in a traffic jam and the temperature starts creeping up.... That's what summer time cruising is all about. Sweeting like crazy with the heat on high, windows down and showing off the Burger King drive thru rough idle camshaft.

I pinch my heater core line in summer. And notice it helps the engine cool a little better. Not recirculating hot coolant from head back to water pump.

Prior owner of my 66 made this contraption - a 3/4 to 5/8 reducer would have been so much easier…

I haven't used this yet 5/8 barbed 1/4 turn ball valve from Lowes or Homie'D

LOL I knew I could count on you to find the humor in that :thumbup:

I've used stuff like that. You can buy smallish valves like that with 1/2" female pipe threads. I buy the barb fittings from a parts store.

Yes, it does work.

I work on school buses. They all have heater valves, and all are common hardware ball valves. Older models had gate valves.

Some of the older buses only used one valve. It did its job. I just didn't trust one valve on my car...

is it better to bypass or block it entirely?

.. or you could just set your heater control valve to the coolest setting limiting coolant flowing through the heater core, but I guess that would be too easy.

Didn't GM-Pontiac have 1 vacuum-pot controlled heater valve, like in 69-70 cars?

Yes my 1970 Van Nuys Formula had a vacuum operated heater control valve, pretty sure only time it was open was when heat was selected they liked to freeze up as in not operate and they would leak coolant as well, i took mine off for the leak when i got the car in the 90's

does a non-AC car even have one?

Just put the valves inline, in the heater hoses. Circulate the coolant to bleed the air out, with the valves open. Then just turn them off in the summer.