FREAKINHEAT

So my car started overheating on my way back from Philly. No coolant anywhere could be seen. I ordered a new thermostat from Dog, and installed. Car still gets hot. Take note the right side fan doesn't kick on, at all. And the left fan starts running as soon as the car starts, then continues to run off and on. What would be the next step in figuring out the temp gauge from rising so quickly?

Now can you guess the which is the no name thermostat?

redpathtribe

It sounds like you found your issue. If one of the fans is inoperative, the car will run too hot and can overheat depending on conditions. In my case in my GT, sitting in summer traffic in Phoenix with only one fan will cause an overheating condition.

If one of your fans is not working, the other may not be too far behind. You should check it as well.

Charley B

Your left fan is also not doing it's job.

mark kibort

right is no name

mark kibort

hot wire both fans and see if that fixes the problem.... plus, if you are overheating, running 60mph would cool it down on the hyway pretty quickly (with fans off) if you have no issues. needle should go to below level at 60mph even with a 90 degree day.

Mrmerlin

I would suggest that you replace following components if your having cooling issues.
Coolant cap,
heater control valve and the short hose,
thermostat and the O ring,
and the rear seal for the thermostat.

To fill the system ,

Put the heater on hot,
fill the bottle till just over half,

run the engine till the fans come on then put on the cap.
make sure the level stays at half while initial running.

Monitor the temp gauge the engine should not overheat while its warming up,
Once the cap is on,
then drive the car for about 5 miles then park it,
let it cool,

NOTE if the engine goes into overheat in less than 5 mins then the thermostat is closed and or the impeller on the pump isnt turning
top up as necessary.

mark kibort

you dont need to blindly just replace things ... you can test them. you can wedge the TSTAT wide open and replace. (just will take the engine longer to heat up, but then when it does and it overheats, you know its not the tstat) however the rear seal behind it, should be looked at to see if it is badly cracked. (its what the t-stat seals to when it opens)

next feel top and bottom hoses. if they are both hot, then pump is working. (also feel radiator. bottom should be Hot/ warm when the car is just starting to overheat) this could be clogged radiator if it isn't. (unlikely) or the pump is not working properly.... test for that is pulling hoses off the radiator and seeing if water flows. . (Using garden hose to keep water flowing to pump and a hose off the water pump to vent water on to the street. ) if you have now flow, pump is dead..... this would lead to overheat all the time though, unless you have a intermittent slipping impeller.

first test... .short out fans and make sure the engine doesnt overheat with both fans blowing. once reason the fans are not turning on, would be the pump is not working, but then the bottom hose should be relatively cool when overheating. normally, both hoses are smokin hot. radiator is almost too hot to touch top to bottom.

FREAKINHEAT

Both hoses were hot. Received a n/used fan. Now the left fan, doesn't come on at start up. Needle stays at half way point then rest at 190. I believe all is fixed. Thanks for the help rennlist!

fraggle

Both fans should operate in tandem. Your final stage is on its way out.

FREAKINHEAT

They both work together now. I should have made that clear in final post.

Mrmerlin

Glad you got the system back into line, have a great summer!
Keep em flying!

FWIW the one fan coming on is a result of the other fan not working.
The fan controller senses this,
then turns the other fan on sooner,
and continues to send a signal to the broken fan till it senses both fans are drawing current.

FREAKINHEAT

Uh ohhhh..... Problem not fixed. Driving to Annapolis, and the gauge again shot up to engine temp to high warning, then the "low oil pressure warning" came on. What can be causing this? Are the two related?

91 928s4

Mrmerlin

have you replaced any of the suggested parts?
Coolant cap,
heater control valve and the short hose,
thermostat and the O ring,
and the rear seal for the thermostat.

How old is the water pump?

FREAKINHEAT

Water pump is less then a year old. Bought from Roger. Thermostat changed out before used fan installed. Have not changed out new cap, or short hose.

Mrmerlin

get a block tester from NAPA and test for hydrocarbons in the coolant.
get an IR gun and test the coolant temps VS the gauge readings you should find about 185 on the top hose and about 170 on the return