Car is running a little hot

[Jimmyvonviggle]

I noticed my car is running a little hot the last time I took it out. Usually stays around 200 degrees, this time creeped up to 220. When I parked it and opened engine compartment, the engine seemed much hotter than usual, and I could hear coolant bubbling from overflow tank.

The next today I took it out again to specifically see if I could here if the fans were coming on. In the past it seemed like they would come on at around 210 and stay on until temp was brought down. Now I see that the fan comes on at a higher temp and when it does, does not stay on for very long.

Thank you for your help.

[Helirich]

The gauges have not proven to be very accurate. You might want to do the same test with a temp gun handy. Point it at the tube where the otterstat is located.

[Ron]

The gauges have not proven to be very accurate. You might want to do the same test with a temp gun handy. Point it at the tube where the otterstat is located.

+1...but, if there is a problem, it could be flow related. So it's better to point at the end of the heads/next to the sending unit...

[David T]

First things to check are the "O" switch, the cooling fan circuit breaker and check for leaks.

[Andrew]

What radiator are you running? 4194 always ran hot with the brass radiator. It would creep over 220 at highway speeds with the A/C on. I installed the Delorean Go radiator this spring. Now it stays around the 160 mark. :-)

[Jimmyvonviggle]

It’s running a new DMC Midwest radiator.

[cdrusn]

I always wonder why it's so important to let the mechanical and electrical systems determine what the temperature becomes. There are a lot of details that make the system run at a certain temperature. Thermostat opens and closes, fans come on or don't, radiator has no air pockets and is clean inside, a/c on or off, car is at speed or in traffic. Why don't you just avoid all of the worry about everything working as designed and just run a wire and bypass the otterstat and run the fans all the time? It won't damage anything and you won't have to worry about if your fans are on or off? Takes 30 seconds to run the wire and remove all doubt.

[David T]

The electrical system was not designed to handle that much of a continuous load. At least with the OEM fan motors. Today you can get much more efficient fans that consume a lot less energy. But it is still wasteful to run them all the time. Every car has a way to run the fans when hot and shut them off when not needed.

[Ron]

I always wonder why it's so important to let the mechanical and electrical systems determine what the temperature becomes. There are a lot of details that make the system run at a certain temperature. Thermostat opens and closes, fans come on or don't, radiator has no air pockets and is clean inside, a/c on or off, car is at speed or in traffic. Why don't you just avoid all of the worry about everything working as designed and just run a wire and bypass the otterstat and run the fans all the time? It won't damage anything and you won't have to worry about if your fans are on or off? Takes 30 seconds to run the wire and remove all doubt.

It's so the oil will be between 230-260°F (colder, it don't clean/dissipate water; warmer it breaks down, heads warp etc.)

Me thinks the electrical system often handles the fans being on full time in hot climates, especially when the AC is on...

[Helirich]

It's so the oil will be between 230-260°F (colder, it don't clean/dissipate water; warmer it breaks down, heads warp etc.)

Me thinks the electrical system often handles the fans being on full time in hot climates, especially when the AC is on...

The fans don't really effect the oil temp. The thermostat does that. There really is no reason the water can't be cool all the time. If you run the fans all the time, you are loading the alternator all the time. I don't know if that wares it out quicker, but it certainly is drag on the motor, so it would lower mpg'. Also, if the fans have brushes, they will ware. Of course some say starting/stoping creates more ware.

In any case, as you mentioned, my fans are on all the time because of the AC.

On my truck (with after market fans) I have a switch that I can over ride the fan controller. I can turn them on at any time, like when I pull up to a traffic light. That way I get a jump on the cooling before the fan controller kicks in. I can also over ride it and turn it off when driving in deep water. Hmmm, don't know if I need that in the D.