1988 Jeep Cherokee 4.0. I have changed everything in the Jeeps cooling system except heater core. I also changed it to in open system, and got all the air out. But I am still running hot, the gauge is hovering in between the two white marks one for 210, the other the white mark before red, sometimes closer to red. I shot the thermo housing with IR and it was showing 228 while the sending unit for the gauge is showing 225. The electric fan is wired to constant run. My question is has any one tried the product Water Wetter by Red Line, does it work is it safe, or could the jeep be running lean and how would I test.

 

I have, on more than one occassion, gotten bad t-stats from the parts store. If you are buying the cheap ones, pony up for a good one. I personally like Fail Safe brand t-stats. I have installed 3 of them, and have not had a bad one yet. I got 2 bad Stants, and will not buy those anymore...just sayin.

When you said "everything", did that include the rad?

 

To check for lean running, pull a couple of the spark plugs and check the color. If they are white, you are lean. If they are between light tan and tan, you should be good. Brown to black = rich.

 

Thanks for the info, I will check the plugs. For the Thermo Fail safe is the only brand I use.

 

Yes new Rad, Water Pump, Thermo, Hoses (All), Changed the pressure bottle to an overflow to accommodate the new rad.