Original Thermostat?

[Richard G.]

I know it doesn't really matter but I am curious.
Could this be an original thermostat for a 1963 Corvette or is it just a weird looking replacement?



Thanks
Rick

[Joe L.]

Re: Orignal Thremostat?

Rich------


The thermostat pictured is a GM #1366373. This is a very early GM thermostat and not the one that GM says was originally used for 1963 Corvettes. Is it possible it was originally used for 1963 Corvettes? Yes, I'd say it's possible, if unlikely. Would I continue to use it? No way.

[David M.]

Re: Orignal Thremostat?

File down that dent on the intake gasket surface under the upper stud/bolt asm. If that and the housing surfaces are not flat you will have a leaker/weeper.
Another tip is to use gasket spray adhesive on the housing side of the gasket and a real thin layer of RTV on the intake side. This tip makes removal a breeze down the road.

[David L.]

Re: Orignal Thremostat?

Enclosed are two photos of a NOS thermostat, GM # 3156280 (Gr. 1.246). GM # 3156280 in listed in my 1963 Chevrolet Parts Catalog (Oct. 1962) for 63 Chevrolets and Corvettes (exc. 292). GM # 3156280 also appears in my 1964-1969 Chevrolet parts catalogs for 1963-1968 Corvettes and Chevrolets.


Dave

[John D.]

Re: Orignal Thremostat?

The worlds best gasket to use for the thermostat is readily available from GM Part #10105135. Its black and has a bead of sealant on both side.
Long ago John Hinckley put me/us onto this gasket. It's very forgiving. Although one should resurface the bottom of the top water on a granite surface plate with sand paper. Doing the top of the intake is not easy.
Is the gasket the correct color for judging you ask? Nope but don't worry about it as you won't have any leaks with the GM gasket.
I buy Made in USA thermostats (Stant) from NAPA. Problem is they typically only stock one of 180 degree at a time. I recently asked them why and the answer was that I was the only one buying them.

[Richard M.]

Re: Original Thermostat?

I know it doesn't really matter but I am curious.
Could this be an original thermostat for a 1963 Corvette or is it just a weird looking replacement?
Thanks
Rick

Rick, Do you have a photo of the bottom view? A friend took this one out of his '54. I've never seen one like it before. I'm not sure if it's GM but I think the date is on it. 4 54

The worlds best gasket to use for the thermostat is readily available from GM Part #10105135. Its black and has a bead of sealant on both side.
Long ago John Hinckley put me/us onto this gasket. It's very forgiving. Although one should resurface the bottom of the top water on a granite surface plate with sand paper. Doing the top of the intake is not easy.
Is the gasket the correct color for judging you ask? Nope but don't worry about it as you won't have any leaks with the GM gasket.
I buy Made in USA thermostats (Stant) from NAPA. Problem is they typically only stock one of 180 degree at a time. I recently asked them why and the answer was that I was the only one buying them.

John, Lately my NAPA gets me TWO of everything as one is usually DOA, sometimes both.

[Gary B.]

Re: Orignal Thremostat?

...Is the gasket the correct color for judging you ask? Nope but don't worry about it as you won't have any leaks with the GM gasket.

John,

What was the original color? Brown?

Gary

[Jim L.]

Re: Original Thermostat?

Rick, Do you have a photo of the bottom view? A friend took this one out of his '54. I've never seen one like it before. I'm not sure if it's GM but I think the date is on it. 4 54










John, Lately my NAPA gets me TWO of everything as one is usually DOA, sometimes both.

Rich,

That looks identical to the original thermostat I removed from my unrestored, unmolested '54 a few years ago.



Jim

----------------------------

[Joe L.]

Re: Original Thermostat?

Rich------


What are the numbers stamped on the bottom of this thermostat? I cannot read them well enough in the photo.

[Richard M.]

Re: Original Thermostat?

Rich------


What are the numbers stamped on the bottom of this thermostat? I cannot read them well enough in the photo.

Joe,

H R D

4 - 5 4

[Joe L.]

Re: Original Thermostat?

Joe,

H R D

4 - 5 4

Rich-----

I had hoped there would be an opening temperature but it looks like there is not. There might be an opening temperature embossed on the top of the thermostat, within the "dish".

HRD= Harrison Radiator Division

4-54----this might be a really old Delco part number.

[Richard M.]

Re: Original Thermostat?

Rich-----

I had hoped there would be an opening temperature but it looks like there is not. There might be an opening temperature embossed on the top of the thermostat, within the "dish".

HRD= Harrison Radiator Division

4-54----this might be a really old Delco part number.

Thanks Joe... next time I'm over my friend's house I'll get a closer look and pics if I see any other markings.

[Jim L.]

Re: Original Thermostat?

I had hoped there would be an opening temperature but it looks like there is not. There might be an opening temperature embossed on the top of the thermostat, within the "dish".
.

The top of the thermostat from my '54 is stamped "145T" in three more or less equally spaced locations.

[Richard M.]

Re: Original Thermostat?

The top of the thermostat from my '54 is stamped "145T" in three more or less equally spaced locations.

Interesting. Could that really be a 145*? I wonder if it still works and what it would start to open at in a pot of heated water?

Here's a snapshot I just took of my 1929-1959 P&A Catalog. Lowest available OTC was a 151*. Interesting it was that value, really? 151* ??

[Jim L.]

Re: Original Thermostat?

I believe the 145T is supposed to represent the opening temperature (more or less), Rich. My dim memory is that alcohol-based antifreeze was in common use back then and that its use dictated lower thermostat temperatures.

This thermostat is stuck closed and that was the reason I removed it in 1998. Otherwise, I would have left it in just to see how many more decades of service it would have provided.

I don't know what to make of that temperature of 151 in the P&A book. Very strange. I've got a couple of old books; I'll check them later today.

Jim