WHY? WATER HEATER SHUT OFF VALVE 33 DODGE

[Sactownog]

JUST CURIOUS, why would they put a Water Heater Shut Off Valve on the engine to stop water going to the heater core? my only thought is for summer to stop the heat from the water going into the vehicle and warming up the cab during hot days. 

 

??

[Matt Harwood]

You are 100% correct. That water circulating through the core adds heat to the interior which is already pretty warm, even if the fan isn't on.

[Rusty_OToole]

You have to look at the style of heater they had back then. A box bolted to the firewall, it could radiate quite a bit of heat on a hot day even if the fan was off. Today the heater core is buried up behind the dash.

[John348]

Later on the heaters had a heater control valve that was inside the heater box and prevented the water from flowing through the heater core if the heater was not on. Some of the GM ones are pretty hard to find and if or when you do they. are very pricey

Edited September 11, 2019 by John348 (see edit history)

[Buick35]

My 35 Buick has one also.Funny I came across this thread,I just got mine freed up today with wd-40 and vice grips. I removed my heater hoses to better show my motor. Greg.

[John_Mereness]

I have seen a lot of shut-offs on the pressure side by the water pump, but also seen some cars with dual shut off's and my thought is cabin heat and/or just dependability of the heater in days of pioneering with cars.

[Sactownog]

yeah, originally I was going to leave it off which is what made me want to ask others the question. it makes sense. mine has always been on (hot water flowing through heater core) but I will replace this valve so I can cut it off. no real need for it in San Diego, CA so the heater is more for looks than function. 

[zeke01]

Have you considered removing the heater from the car? Space is at a premium for feet in those cars. In addition, there would be fewer places to lose coolant and two fewer hoses in the engine compartment would mean less clutter under the hood. Zeke

[Rusty_OToole]

Chrysler used a neat shutoff valve that was spliced into the heater hose on millions of cars and trucks in the seventies and eighties. It was controlled by a cable like a choke cable. It would be a cinch to install one on any car, and control it with a choke knob on the dash. They cost less than $20 bucks. This would replace the valve on the engine, that you have to lift the hood to open or close. So, more convenient especially in spring and fall when the weather is changeable.

 

Four seasons heater valve from Summit Racing $14.99

 

[Buick35]

13 minutes ago, zeke01 said:

Have you considered removing the heater from the car? Space is at a premium for feet in those cars. In addition, there would be fewer places to lose coolant and two fewer hoses in the engine compartment would mean less clutter under the hood. Zeke

 

[Buick35]

I kinda like the looks of an old heater,especially if it's original to the car.

[Graham Man]

Not sure if any car had a "standard heater" before 1940?  Graham offered heaters as an option around 1932 but most were dealer installed aftermarket parts form Tropic Aire and others.  Most cars were parked for the winter, mostly for lack of decent antifreeze, that got better after WW2.  My Grandfather used a alcohol mix for antifreeze into the 1950s in his/my 1933 Graham.

 

1935 ad says they sold 200,000,000

 

[Marty Roth]

On 9/10/2019 at 8:06 PM, Rusty_OToole said:

You have to look at the style of heater they had back then. A box bolted to the firewall, it could radiate quite a bit of heat on a hot day even if the fan was off. Today the heater core is buried up behind the dash.

 

I've also installed manual shut-offs on cars which did not come with them.

Our black 1937 Buick absorbs heat from the outside, and the firewall-mounted factory heater was providing more than we desired, even when the fan was not turned on.

 

A non-functioning factory valve was supplemented by a manual cutoff in the Corvette, as well.

I'm perfectly capable of opening/closing the valve when necessary to keep BOTH of os happier and touring.

[John_Mereness]

Try a couple hours of driving  in a 1930's car - you can fry an egg on just about any part of the car - nice to have the heater shut off.

[JACK M]

On some of my older junkers I found that valve to be of some convenience to extra cooling of the engine.

I would rather put up with the heat in the cab than to experience  boilover.

[chistech]

The biggest mistake is everyone puts the shut off on the feed side and it should be on the return side close to the pump. 5he reason being if it’s on the feed side, the hose could be collapsed by the suction. I have a copy of the 1932 Olds technical service bulletin for installing the Harrison Senior heater which was a GM heater, dealer installed. The bulletin says to mount the valve as I described for the reason I gave.  I believe Chevrolet had the first private labeled heater in late 1931’, again made by Harrison 

[Guest]

 

7 hours ago, chistech said:

The biggest mistake is everyone puts the shut off on the feed side and it should be on the return side close to the pump. 

This makes total sense.  If the return side is stopped the inlet side cannot conduct hot water to the heater.  For once we see correct data, not some made up reason.

Thanks for sharing chistech.