My temp gage is running hot. I have 1300 miles on my rebuilt 98.5 Cummins 24 valve.
First trip, temp gage stayed under 1/2 the whole time. Highest egt's. I seen was 1140 or so..
2nd trip the temp gage stayed under 5/8 or so. The highest egt's I seen was right at 1200..
3rd trip the temp gage went up to 3/4 or so. The egt's went up to 1240 before I let off to not see 1250 (the melting point of aluminum)...
Each trip was around 400 miles, early in the morning so road Temps were about the same, and roughly the same road grades...
What could cause this??
I am wondering if I can put a lower tempature thermostat in it??
Any and all advice will be greatly appreciated!