chiliphil1

I Have a 94 ls, stock B18B. The first problem I noticed was that the cooling fan was not working. Through this site I found how to test the radiator fan switch, and by jumping the connector found that the fan works when the jumper is in place. From running that test I also tried to bleed the cooling system by filling the radiator until coolant comes out of the nipple where the hose attatches, and then letting the vehicle run for about 20 minutes with the cap off, and the heat on full blast. During the bleeding process the fan did not come on once. The second issue I have noticed is that the lower radiator hose does not seem to get warm, it stays pretty well cold, and the upper gets so hot you can't touch it. The temp gauge reads perfect, just to the left of center, and does not fluctuate, it even starts out cold and rises at a normal rate. The testing I have done based on info from this site leads me to believe that the fan is not working due to the switch which will be replaced asap. My question is, with the lower radiator hose not getting hot while the engine is running, and also the veh does not overheat, even at idle on a 100* day, is there also some other issue? shouldn't the lower hose be warm like the upper? any more testing I need to do? Any help would be greatly appreciated. Thank you.

ethos0518

The lower hose didn't get hot and/or the fan wouldn't normally come on if you had the heat on full blast.

Turn the heat dial to cold. Drive around. Then your lower hose will be hot.
My fan fuse was blown for who knows how long...months or a year. My car drove the whole time normally and NEVER overheated or "got hot" until a worn out heater hose developed a leak at a clamp. Only then did I see the fan fuse was blown.

If you want to test again. Cap the radiator, run the car, heat OFF, and rev the motor up to 3000rpm off and on in 5-10 second intervals with your eye on the temp gauge....either the temp will rise past halfway (shut the car down) or the fan will kick on.