I just bought a 97 1500, 318 with 100,000 KMS on it. Under normal driving my temp fluctuates. It never goes into the red, but it gets 3/4 of the way there before the thermostat opens and the temp drops back to normal. I've had a couple of 318s in the past and don't remember them doing this. I had the rad flushed the other day, am I right in suspecting the thermostat should be changed? Is this normal or is there something else I should check?

Thanks in advance!

 

Thermo controls engine temp, so that'd be the problem most likely. Maybe whoever you got it from but a hotter temp thermo in there, but I doubt it.

Change the thermo and see if that solves the problem

 

go with a 180 t-stat and drill a small hole (real small) in the diaphram to allow air to escape during fill up.

 

Not only that, but flush the entire system, including the overflow.

 

I've seen posts about changing the t-stat to a different temp. Whats the benifit of the 180 over stock?

 

My coolant and overflow were rust colored so I flushed it, and 3 days later is was rust colored again. Do I just need to flush it again, or does that indicate a bad water pump or something??

 

How long did you flush it? I'd take it to someplace like Jiffy Lube, where they power flush the system for about 15 minutes, including a reverse flush. Sounds like you have a lot of crud in your system. Change the t-stat, fill with water, and take it in to get flushed. RUnnign straight water for a short period of time won't hurt.