Temp gauge issues

[bridgeman]

Should have done a radiator flush first. Flush all the rust out of the system first. I found some large deposits restricting the coolant flow in engine block. Flush the system 2 times as was amazed at what came out. The temp gauge reads fine now and the truck does not run hot and the heat works way better now.

Bridgeman

 

[Miami-Yukon]

You could have a hot pocket of air in the system thats causing it.... Try starting the truck and then manually reving up the engine a little and pouring in coolant/water mix unitl it wont take any more...

My truck gauge runs at 210 deg all the time while my scangauge II shows the truck at 198 deg all the time. I think GM did it that way as sorta a dummy gauge that way you the motor doesn't get as hot as it shows....

Just some knowledge I've learned growing up on the GM 350's...

Bu t I'm not a mechanic, only general knowledge!