Thermostat orientation

1930artdeco

1930artdeco

Well-known member
Hello,

Quick question, Which way does the thermostat go? Spring away from the radiator or towards? I had it way from the radiator in manifold and the top tank got to 10 but the core was 70:eek::confused:. I am affraid to run her again until I get her to cool down. The timing will need to be adjusted again as well.

Thanks,

Mike
 
1930artdeco said:
Hello,

Quick question, Which way does the thermostat go? Spring away from the radiator or towards? I had it way from the radiator in manifold and the top tank got to 10 but the core was 70:eek::confused:. I am affraid to run her again until I get her to cool down. The timing will need to be adjusted again as well.
Thanks,
Mike
Click to expand...
Celsius or Fahrenheit or ???
You've got me confused with those numbers.
The coil spring side points into the engine, so the thermostat can sense the temperature of the coolant in the engine.
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I’m going to a$$ume you’re using centigrade readings. 70C is only 158 F, so even a 160 stat won’t be opening. So the radiator tank won’t see any heat.

Did you drill a small bypass hole in the stat? Sometimes they trap air up there, and don’t see the heat until expansion gets water into contact with the stat. You’ll see a reading with an infrared based on the metal heat transfer, higher than what the stat sees.

Did I say that so it makes sense?
 
1930artdeco said:
Ok, I had it correct then. Now to figure out why the engine got hot but the core never warmed up.
Click to expand...
When was the last time you looked at the inside of the water pump or radiator? I've seem photos of water pumps with the vanes rusted off... and the radiator could be clogged.


.
 
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The pump is a new Napa one and rad has been rodded out. With the IR gun the top tank is about 170 and when I shoot the core (about three or so inches down it is 70-both F degrees. That is what is throwing me. I am used to the model A where the core is 160ish, so a pressurized system is new to me so to speak. Also, the gauge pegs on H and the manifolds are in the 3-400* range with a new engine. So I am willing to be called paranoid-just so long as I don’t do something stupid and break the engine.
 
Ok, I get your readings now. What’s the thermometer housing read when the top tank is 170? And the temp sender location at the rear of the driver’s side head?

170 to 70 sounds like too big a drop, especially given our ambient temperature up here right now.

300-400 degrees at idle on the exhaust manifolds might be a bit high, I’d be looking at the timing at whatever rpm you’re running. Total timing, don’t disconnect the vacuum advance if you’ve got one. Hard pulls on the dyno with my Yblock runs the headers red hot, 1200 or more. But that’s extreme conditions.

Are the square corners both forward and inboard on the head gaskets? Reversing them causes water flow problems in the heads.
 
I popped the thermo out to make sure it was installed correctly and it was (spring in the manifold). So maybe this weekend I can reassemble her and fire her back up. I will have to retime her with the vacuum plugged according to the manual first-I kinda forgot to do that before. Then I will post readings.
 
Mike. On my yblock I believe it's got the 180 stat on it. While driving here and there is goes up to 200 and when I get back to idle in some spots it goes back to 180.
FYI I went to the steel six blade fan from the southwest Thunderbirds. But also have not had a chance to add a good fan shroud.

The test above a great way to check if it's opening.
 
When testing the thermostat by placing it in a pot of water, it should only begin to open at its rated temperature. It should be fully open by an additional 20 degrees or so.
 
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