ryantlq

At what temp should my electric fan come on? I have a stock '89 L98 automatic and it seems to be running hot. The fan will come on if the a/c is on but will go off when I turn off the a/c.

rodj

http://forums.corvetteforum.com/c4-t...oling-fan.html

ryantlq

Thanks guys. It looks like I may have bailed out early. When the engine got to 225 and no fan, I decided to shut it down. Today I'll try and get it up to 235.

SunCr

Except the '89 specs (non a/c) are 226 for the Main; 228 for the Aux. Main is driven by the ECM with input from the Coolant Temp Sensor; so if you want to see what that is, you'll need a Scanner. The Dash Gage gets it's input from a Thermistor screwed into the right head and can show a temp differential of a couple degrees. Aux is from a switch in the left head. Aux should rarely if ever come on. Check it by blocking air flow - or if it is coming on, that's a good indication of a cooling problem. With a/c, Main is driven by the ECM (regardless of Coolant Temp) when a switch on the High Side opens at around 220 psi. You'll need a Manifold Gage Set to check it.