Barefooter6

I have a 1983 300sd. I have replaced the radiator, thermostat, waterpump and bled the air out of the system. The car still wants to run at a temp just below overheating. Any answers?

waybomb

Did you verify the gauge is accurate?

Does the electric fan work? When the radiator gets hot, does the fan clutch engage?

Do you loose any coolant? If so, may have a bad head gasket.

Barefooter6

Thanks, The guage is accurate, the elec. fan works, clutch fan is new and I'm not losing any water.

morris374

try a higher concentrate of coolant like 70% coolant 30 %water rather than 50-50

oldsinner111

As these fine diesels age,it is important to flush and clean block good.I use one gal vinegar added to water with thermostat out.Run car really good a hour or more driving.Then drain,when block is cold run water thru engine backwards.You will see chunks of rust.Run her in summer with plain water till all rust is gone,then fill her with antifreeze and distilled water.

Barefooter6

Thanks, I will try that this week.

waybomb

50/50. Everything I've read on the websites of antifreeze manufacturers says 50/50.

If you can show me some proof that 70/30 is better, I'll accept and change my opinion. But when a marketer of a product says less is better, I gotta believe them.