Chas,

       If the gage turns out to be OK, try another thermostat. If it's rated at 180, and if it actually closes below that, you ought to see at least 180 in the head. 

Frank/Rebop

Bristol, In ( by Elkhart) 

The gauge should be alright. I've had 2 of them and both read the same. They are made in China so who knows how accurate they really are. Didn't notice the made in china part until I had the installed the 2nd.



I put my hand on the radiator core this morning once I got to work. It felt maybe luke warm, if that. Even at 140 it should burn after a few seconds if water is flowing through. The upper radiator hose was hot, though. Is it possible to sustain a low operating temperature without requiring the radiator if the ambient temperature is low enough? Say 50 ambient.



The radiator is a reproduction heavy duty unit. It's a good sized radiator. Much larger than the ones in pickups I've seen at the junk yards. My old engine, while it ran hotter than this one, still ran colder than I thought it should. It would get around 160 with a 180 stat but that seemed to be all year round.



I will posit that the water is going through the radiator and the radiator is too effective when full airflow is applied. The result is magnified with lower ambient temperatures.

When I put my hand on it, I could barely feel any air being pulled through so it is no wonder why it gets hot if it just sits and idles. Need a shroud.

Still need to get the thermometer.

It's a 50% chance of rain tonight.



Lawrenceville, GA

Well, it rained.  That's Murphy for you.


Lawrenceville, GA

Going back to your temperature gauge reading cooler than you expected:  Having the temperature sending unit at the back of the engine will typically net a lower gauge reading than the thermostat rating due to the water at the rear of the engine not being fully heated by lieu of not having travelled forward yet through the heads.  Moving the sending unit to a position right behind the thermostat will give a higher temperature reading without changing anything else on the engine.

Lorena, Texas (South of Waco)

Your problem might be the heater core. It might be cooling the engine enough to prevent it from allowing the thermostat to open up. You might need to put a restrictor in the heater hose to slow the flow of coolant.



In my 86 Mustang there was a heater hose restrictor. It was a round metal rod with a 1/4" hole through it. My heater still works with this restrictor in it, so that's not a problem.



When I went through my Mustang's cooling system, I put in a cleaned 2 row radiator, a new Ford heater core, a Ford Mustang 'export' water pump, a Robertshaw 180 thermostat, synthetic motor oil, and water wetter with a 2:1 water/coolant mixture. It ran too cold and the engine's computer wouldn't come out of open-loop mode. I put in a jobber 195 thermostat from the local Schlocks/Cracker auto parts store that is pretty flaky, but gets it up to temp.



I need to get a Robertshaw 195 put in there some day.

Best regards,



Paul Menten

Meridian, Idaho

The infrared says its about 190 in the thermostat housing. The gauge, being that it's made in china, is probably crap. The inlet of the water pump was reading about 155. No way it cools once back inside the engine. So, I'm probably good. Need to check it again in the summer. If the gauge reads hotter, I wonder if it actually is hotter.



I still don't think I should be able to touch the radiator core without burning my hand, though.


Lawrenceville, GA

Charlie,

          had a simular problem this spring with my truck. After doing a bunch of different things, it ended up being the constant voltage regulator behind the speedo, replaced it and it was very accurate after that comparing it to a borrowed inferred gun I used.  But in your case I don't think its that if your able to put your hands on it without getting burnt. One thing too Steve we used to do in Wisconsin growing up insted of cardboard, we'd just take the fan off all together, just wouldn't let it idle too long!

                                                         Michael

Michael

Sandy Valley, NV

Charlie:

An added note.  The temp sensors on the end of your arms, for most people, 130 degrees is about the limit you can stand to leave your hands on something hot, it's uncomfortable but not painful at that temp.  Above that it starts getting painful.  Just a rule of thumb (pun intended), differs with some folks.

John

John - "The Hoosier Hurricane"

That's interesting. I would have thought the pain threshold is lower than that. It feels much cooler than that, though. In some spots it feels like it may be slightly above ambient. I'll shoot the infrared on the core to see what it says. I haven't gone around touching radiator cores before. I wonder what the car is like.


Lawrenceville, GA

Charlie:

You are probably not touching the tubes with the hot water in them, you are touching the fins which help dissapate the heat.  The hottest part of the radiator would be the area where the top hose goes into it.

John

John - "The Hoosier Hurricane"