Hello everybody i recently just bought me a 1997 Chevy K2500 6.5td F engine the problem is it seems to run a little hot out here in arizona due to the 115 degrees outside. I ran this truck in Wisconsin were i purchased it and never jumped over 1/4 of tempature but its alot cooler down there, My truck now runs between 2/4 and 3/4 of tempature and seems to lack on power when hotter im running 15w40 now in summer just did thermostats and flush no change should i run a heavier oil due to the heat outside put some kinda additives or any ideas???

Help anyone !!!

 

Did you use a/c delco thermostats?

 

Remove and clean the rad with scrubbing bubbles and blow out all other coolers with low pressure compressed air and/or low pressure water.

Also straight water with water wetter cools better than an antifreeze mix,the less amount of antifreeze you run the better as long as you provide enough protection for the conditions the truck will see.

AC Delco ONLY for thermostats,Robert Shaw are supposed to be ok as well but all others do not work properly in these trucks.

Also inspect the fan clutch,if the spring in the center is damp or has fur on it-it needs replaced,I have had great success with the Kennedy Diesel special calibration clutch as it was designed from the get go to engage earlier-all other clutches engage too late for these trucks including stock GM ones.

A google search for 6.5 fan clutch mod will teach you how to modify a stock clutch for earlier engagement if it is still in good condition.

Fan clutches are a maintenance item that seldom gets replaced or even looked at,the dealership I worked at had a replacement policy every 3 years on vehicles that came in-don't know if that was local or a GM directive?

 

Racer55 thanks very much for the reply i appreciate it very much i used the duralst 195s i couldnt find any auto zone that had the 185s wer can i find the ac delco? im gonna go step by step cleaning the radiator and moving on to the fan clutch. And question abou the water wetter is that a better source to move to then antifreeze ? i hardly tow anything with my truck so its never really under any load.

 

You will probably need to google AC Delco distributors in your area or get autozone to special order Dual thermostat: AC Delco:# 131103 or GM #12559336 times 2.

the water wetter is a lubricant for the waterpump and I think it conditions the water some as well-if you see temps below freezing then some antifreeze to protect things is still needed.