Steve_bigD

1938 Buick heater shutoff valve

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I am installing a water shutoff valve in my 1938 Buick 40-41 so the heat to the core can be shut off in summer and was wondering if it it makes any difference if it installed in the input line from the thermostat housing or in the return line to the water pump? 

 

Thanks,


Steve D

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I guess I probably chose the inlet, but it really doesn't make much difference.

 

Jeff

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Adding a valve will stop the fluid flow and then all you will have is heat conduction thru the closed valve which is minimal.  Normally a valve is installed on the pump side of a heater core.  If you have a leak in the heater core, the valve would minimize the pressure on the heater core.  

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Thanks for the responses. I think it is easier to rout the hoses if I put the valve on the inlet side so I'll probably do that.  I also found the drawing below showing the heater hose routing.  Note the top hose goes to the bottom core inlet.

 

Steve D

heater hose routing.jpg

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21 hours ago, Steve_bigD said:

I am installing a water shutoff valve in my 1938 Buick 40-41 so the heat to the core can be shut off in summer and was wondering if it it makes any difference if it installed in the input line from the thermostat housing or in the return line to the water pump? 

 

Thanks,


Steve D

 

Hi Steve,

Thanks for the installation details, that is priceless! Any chance you could post some photos of the valve and your installation. I need to do the same on my ‘38 and need to locate a suitable period valve and fittings.

Rodney 😀😀😀😀😀😀

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For what it's worth, my '41 has a shut off valve and it's at the thermostat housing end.  I don't know if this was installed at the factory or not.  It was on the car when I bought it.

 

Thermostat_housing4.thumb.jpg.1f12e515b873a409c87be8791ce4e7d8.jpg

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We installed my manual shutoff on the inlet side for our 1937 80C

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If I can add my two pennies worth, I have just installed my shutoff valve on the lower connection thinking this is the inlet. However the top hose is much hotter on warm up, so thinking the top connection must be the inlet. 

 

Looks like I might have to refit the connections so the shut off valve is to the top. ☹️☹️☹️☹️☹️

 

Just have to reclaim some of the coolant which may not be so bad as I can use the shutoff valve as a drain.

 

One step forward, two steps back, tis all a big learning curve..

 

Rodney 😀😀😀😀😀😀😀

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Ok so that’s done and heater performance is now terrible.

 

Reversed position of the shutoff valve so now it sits on the top outlet on the thermostat housing, and the heater does not warm up at all. Put a blanket over the front to promote a quick warm up but still no heat. Ran it on idle for about 30minutes, temp gauge showing about 170 so you would think things would be warm.

 

Wonder if I have caused an air lock in the heater system when changing the fittings. Heater hoses feel warm near the motor but colder as you get closer to the heater.

 

As an aside, I did modify the bypass valve spring  as recommended.

 

BTW this is all just in the garage as I haven’t Road tested it yet. ( but it should still get warm )

 

 

Rodney 🥶🥶🥶🥶🥶🥶🥶🥶🥶🥶🥶🥶

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You may want to road test it.  Adding some rpm to the pump may make the difference.  I cannot say whether or not this is true on my '38, but I distinctly remember my 1970 AMC Hornet - perfectly good heater output, unless you were idling on a very cold day... heater temperature dropped off to nothing, warming up again as I drove off.

 

Jeff

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Have you flow tested the heater coree to be sure it isn plugged?

It should work fine the way it is plumbed

The heater will drive you out of my "38's

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On 6/18/2019 at 11:16 AM, neil morse said:

For what it's worth, my '41 has a shut off valve and it's at the thermostat housing end.  I don't know if this was installed at the factory or not.  It was on the car when I bought it.

 

Thermostat_housing4.thumb.jpg.1f12e515b873a409c87be8791ce4e7d8.jpg

 

I literally thought this was a photo of my engine. I gotta change those hose clamps!

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2 hours ago, Matt Harwood said:

 

I literally thought this was a photo of my engine. I gotta change those hose clamps!

 

Something wrong with my hose clamps? 

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2 hours ago, neil morse said:

 

Something wrong with my hose clamps

Wrong clamps for any type of judging.

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6 hours ago, DonMicheletti said:

Have you flow tested the heater coree to be sure it isn plugged?

It should work fine the way it is plumbed

The heater will drive you out of my "38's

 

Hi Don, yes I had the unit checked by my radiator shop before installation, so all is good.

 

8 hours ago, Steve_bigD said:

Here is a photo of the heater shutoff valve I just installed on the top hose:

 

 Steve D

20190712_144640.jpg

 

Hi Steve, Many thanks, that it how mine is now!

 

Did a road trip this morning and heater is getting hot as it should. So looks like all is fine. I had the core tested prior to installation so I knew there were no issues there.

 

Just gotta wire the fan to a proper switch so I can have that running as I was only testing by connecting to the lighter connection. And make up the bracket to hold the hoses.

 

many thanks to all that contributed,

Rodney 😀😀😀😀😀😀😀😀

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1 hour ago, 61polara said:

Wrong clamps for any type of judging.

 

Are you judging me? 😉 My car is a driver -- I'm not concerned about judging.

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As far as originality goes, I dont think I have seen an original hose clamp on a Buick that actually had the "BUICK" logo on it or was stainless steel. They all were just plain steel .

 

Can someone enlighten me where it is shown where the stainless clamps were original?

 

If I am right hose BUICK logo stainless clamps are "overrestoring"

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I didn't mean anything by it, Neil, and wasn't making fun or anything like that. Modern hose clamps are just one of my pet peeves, although as I said, that photo looks IDENTICAL to my car, hose clamps and all. I have a set of correct ones that I plan to install when I replace the radiator and water pump, but at the moment, the thing runs ice cold and I don't want to risk messing that up!

 

Hose clamps and fasteners are little things that I notice that bug me on old cars, although I realize I'm in the minority and most folks don't care. They jump out at me, but that's probably because of my profession more than anything else. I certainly wasn't implying that I don't love your car or that the hose clamps are unacceptable or anything like that. Sorry!

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No need to apologize, Matt!  I figured that's what you were reacting to, but I just wanted to make sure there wasn't some problem I wasn't aware of.

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On 7/13/2019 at 12:19 AM, neil morse said:

 

Are you judging me? 😉 My car is a driver -- I'm not concerned about judging. 

Neil,

Not judging you, just responded to someone's question about what is wrong with the clamps.  I have the aircraft style clamps on most of my drivers as well.  Better than what the factory put on.  Enjoy your car!

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