Temp Guage

[Wheezy]

Recently I have noticed the temp guage moving around... . Normally it will sit just under the halfway mark. I have noticed under heavy acceleration that it will jump up to the halfway mark or just a hair above. It goes back to normal pretty quick, but has me a little worried. The other day I was hauling the load below (about 6000 lbs), and it went about 1/4" above the halfway mark, we were in some heavy traffic, and from stoplight to stoplight was about a 1/4 mile. I was giving it more throttle than normal, but nowhere near full throttle. I have checked coolant level, but other than that, I thought I would see what you guys suggested. The guage fluctuates loaded or unloaded, but of course is more apparent when loaded.

Thanks for any and all info



John

 

[rbattelle]

I really don't think you've got anything wrong with your cooling system. I have an OBD-II system that gives me a numerical readout of ECT (among other things) at all times when I'm driving the truck. I have never towed anything (other than random people out of ditches). When the factory needle is AT the center hash mark the coolant temperature is around 196. Running 75 MPH up a LONG hill unloaded I've seen ECT climb as high as 196 (after thermostat opening), and the needle was at the center hash mark.



I ran some quick calculations and assuming a 16 psi radiator cap pure water coolant won't boil until 249 F (I can show the equations if anyone wants verification). You've got a 50/50 mix of glycol and water, so the boiling point will be much higher than that (I didn't run those calculations... maybe I should). Anyway my point is don't worry, you're probably running up in the low 200's (maybe 200 - 210) when you see the needle 1/4 inch past center. As long as it drops when you get moving some air through the radiator then everything's fine.



If I've said anything wrong here, please someone correct me. I'm not an expert in automotive cooling systems...



-Ryan

 

[Wheezy]

Thanks for the info, it is appreciated



John