I just installed a Mr Gasket 180˚ High flow thermostat. I checked in a pot of water to make sure it was opening at the right temp. It worked perfectly.

I am finding however that the car runs at a cooler temperature than it did with my 170˚in the same outdoor temperature (170˚ also a high flow) . The engine barely gets up to 1/2 way on the temp gauge. It takes forever for the car to get up the operating temp. Its still cool here in Canada but relative to my 170˚ the car runs way cooler. I thought the 180˚ was to get the car to warm up more quickly and run at 180 minimum.



any thoughts



Thanks

The 180 may not be closing correctly, or the 170 was not opening at the correct temp. Also might check and make sure the 180 is sealed up on the gasket correctly.

Frank/Rebop

Bristol, In ( by Elkhart) 

The new thermostat has been tested and is opening up correctly at 180°. Maybe the old one wasn't opening up at the temp it should have. Do you still have it? In any case if everything else in the system is unchanged, the difference in temp must be with the thermostats, right? My water temp runs in the 170s on most days unless ambient temp gets really hot here in CT. When the weather gets 40° or so hotter in summer, the operating temp will go up some.

If the outlet water temp is really 180° - and being regulated at that - then the gauge value you see doesn't mean much. Is the outlet housing running up to 180°? Infrared thermo tester available? The spec thermostat for a Thunderbird opens at 157° per the manual.

Few of the large poppet thermostats are as good at moving water as the "Robertshaw" type - which the Mr Gasket is - your 170° wasn't quite like it was it? The old thermostat might not be as efficient at moving water as the new one

Have you changed anything else? Larger fan or radiator size - blocked bypass hose (short one under the thermostat) - opened up RH exhaust thermal valve, stuck or wired it open - blocked heat crossover passages in the intake manifold?

One big change I made to my outfit was getting rid of the old "Load-O-Matic" distributor and setting up the idle spark advance. The old system - with the 6° spec initial advance ran so retarded she was hotter than a firecracker. Dropped idle temperature immediately to go to 10° initial and 7° of vacuum advance (at idle). 

 
 Steve Metzger       Tucson, Arizona

The 170˚ thermostat was functioning properly as well. I checked it when I took out and compared to the 180˚. Does the thermostat stay closed until it reaches 180˚? I have noticed the upper rad hose starts to build pressure well before it gets it to 180˚. What is the optimum thermostat to run on a stock 312? I will wait and see what happens once we start getting warmer weather. I may go back to my 170˚ Nothing else was changed on the car except I had to replace Heater valve on the manifold due to it leaking.





Thanks

It is getting to 180. The engine simply will not stay cool unless the thermostat is open and allowing coolant to pass through the radiator. You can verify the temp with an infrared or laser thermometer aimed at the thermostat housing.



The thermostat should not affect the time it takes to warm up. No matter what thermostat is installed, you still have the same volume of coolant to heat with the same fire.

I do notice that my Y appears to take much longer to warm up than the 305 in my Firebird. One significant difference that I notice is that the coolant bypass is in the block on the 305, and I presume all other sbc's. This would keep the coolant in the heads to get the combustion chambers heated up quickly and since the temperature sender is in the intake it registers warm, sooner.



You want at least a 180 degree thermostat. The hotter you can get it without boiling over, the better.


Lawrenceville, GA

Hi Charley.

I am comparing the time it takes to warm up based on my 170˚. My 180˚ takes forever and it does not get up to 180. I did an experiment last summer.

I took off the rad cap, started up the car and let it get up to operating temperature. I put a BBQ meat thermometer in the rad. The coolant would get up to about 175˚and hold there at that temp. The temp gauge needle would be pointing straight up (midway point on the gauge) . I know this is bit primitive but at least it gives me an idea of the coolant temp as it comes out of the upper rad hose. I drove the car today. It was about 50˚ outside and temp gauge barely got to 1/4 of the way. If i drive the car close to an hour or so it will get closer to the 1/2 point (175˚) Again nothing has changed except for the Mr Gasket 180 Hi flow thermostat and the Heater valve. I have read that these Mr Gasket thermostats have had issues.

The radiator is not the best place to check the temperature. The coolant has had a chance to cool some, particularly if you're getting the reading from the core. Since you checked the thermostat, and it is opening, it is at least 180.



"... and the heater valve"



is the valve in the same position as it was before - on or off? The heater core is a second radiator if coolant is now passing through when it was not before, it will take longer to warm up.



Another thing is you're comparing spring (it is still spring, right?) ambient temperatures to summer ambient temperatures. You will not get the same reading. My truck runs about 20 degrees cooler in the winter than it does in the summer, though if I check the temperature at the thermostat housing it's always at least 180 degrees (since I have a 180 degree thermostat installed). In the winter, my guage indicates about 160 and it is pretty accurate. The location of the sender will always result in a lower temp than that at the thermostat housing.



Did you perform the modification to the thermostat where 3 holes are drilled to help bypass more coolant? I'd think that will make it take longer to warm up. I did not do that to mine but I am considering doing like Steve did because I am in a warmer climate.


Lawrenceville, GA

I had a similar result with a Robertshaw style 180 thermostat.  Took forever to warm up to 180, like 15 or more minutes.  Underway temps would not go above 160 unless driving 65 plus mph at 85 plus ambient, or standing still, or idling along in a parade.

The Robertshaw was changed to a Delco Harrison a month ago.  Similar issues, though it does look like the stat runs about 5-10 degrees warmer than the Robertshaw while underway.

Temps have been verified, stats checked for opening closeing temps.  No solutions here .

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

Never had a problem with my T-Bird running too cool. Wish I did.