Low temperature: Thermostat or cold outside

[OldDominionIron]

So I've finally been able to take the deuce out for a drive, to work one day about 50 minutes away. Outside temperature was in the low 40's, and the temperature never got above 165F. Is this due to the cool ambient temperatures, or possibly the thermostat sticking open. I'm going to the beach in NC this weekend, about a 2.5 hour drive and was wondering if I should block part of the radiator to get the temp up closer to 185. Also, what are the affects of running colder. Can I expect a performance boost when I finally fix this temp problem. I've search threads, and the questions I've seen all deal with overheating. Thanks for the help.

 

[Snarky]

I had the same problem, I replaced the thermostat and it still runs cool, even when it's warm outside.

 

[jblack6527]

I've noticed mind does the same thing. Usually if the thermostat is stuck open, they will just take FOREVER to get up to temp. If it's 50 degrees or below, I always just cover the majority of the rad with a piece of cardboard. It you cover it too much, just pull over and move it until it stays where you want it.

 

[ctmustang]

You want really see a performance increase with warmer engine but they are intended to run at 185. Running them cooler causes the engine to really build up alot of carbon inside which is a bad thing.

 

[rockman]

Might need to put a frony cover on it. I put one on my old truck as it always ran cool. Left it on year round and just opened the flap more. The cooling systems are pretty efficient.

 

[antennaclimber]

My Deuce was usually around 180 degrees. Recently I cleaned the cooling system with some radiator flush from NAPA. This removed a considerable amount of brownish fluid from the system. The coolant in the top of the radiator always looked its normal green color prior to flushing. I installed a coolant filter kit and refilled the system with new coolant and distilled water. I also installed a new thermostat and heater hoses.

After the above work was completed I noticed that my engine temperature was now running about 15 degrees cooler. So I put a large piece of cardboard (painted OD green) in front of the radiator and the engine temperature is still running around 165 degrees.

After driving the truck and getting the engine temperature up, the temperature does not decrease more than about 5 degrees during the idle cool down period.

These trucks do indeed seem to have a very efficient cooling system. Perhaps to efficient.

 

[Carl_in_NH]

The stories I've heard all indicate that below 50 F, you need a winter front on the vehicle (or some other method of covering up some of the radiator). Based on a sample of two trucks, I agree; in colder regions, it will never warm up properly without some blockage of airflow over the radiator.

I bought the winter front kit for $35 - that solves the issue nicely.

 

[ENCS_DEI]

It may be your gage. Mine reads about 25 degrees low when checked against an IR temp gun.

Russ

 

[IMA944T]

I had a problem with mine not warming up also. Even when it was 80 degrees out it ran around 160 and now that it's been in the teen and around zero it never wants to warm up ( 120 degree) unless driven on highway. I would think thermostat also. I have covered part of the rad with something and the temp stay around 180 unless driven on highway for a while the I slide it down to keep temp from the 195 area. Runs alot better around the 180 to 190 degree.

 

[treeguy]

Its a bad temp sensor! I had the very same problem, the gauge would never get above 165 no mater what the outside temp. Whole thing was driving me nuts. I replace the thermostat, topped off the coolant, and bled out all the air and still no change. I got a lazer temp. gun, ran the crap out of the truck and checked all over the manifolds. Sure enough everything was at operating temp, it was just a bad sensor.

 

[TexRdnec]

mine has never gotten above 165 either..............and the fuel is never right.................and the oil pressure always reads low

why do these ****ed things even have gauges?

 

[jatonka]

The cooling system is too good, ask Cranetruck, he has anaylized it all the way and the M35A2 runs too cool. Winter front or cardboard, your choice. Some of us run Winter fronts all year around. It ought to run at 180 degrees for proper efficiency. Trucks with heaters shpould have a 195 degree thermostat. As far as low oil pressure readind, put a mechanical gauge in it now, be sure you are OK. Any auto parts will have mech. oil pressure gauges for cheap. If you need the exteral oil pressure regulator, I can get them. JT out

 

[jwaller]

take a piece of cardboard and cover about 5/8 of the radiator front. you can raise the hood about a foot and slip it in from the top.

 

[glcaines]

My Deuce runs about 180 - 185, even in very cold weather, although it takes some time to come up to temperature when it's very cold.