big time cooling problems

[EZ4U2ENVY]

Im gonna replace my t-stat again to see if it helps. But what i was curious about is there a good t-stat avail and what are the part numbers for them? any help would be appreciated

 

[projectSHO89]

What were you expecting a new t-stat to fix?

We are not psychic!

Steve

 

[EZ4U2ENVY]

lol...i know that-

problem- after a few min of driving temp gets into normal range- than sitting or driving for a few more min results in guage going to nearly red- than few seconds later rushes back down to the L in normal does this constantly but sometimes stayes way close to the red.

I also only get heat when it climbs fully to the red and when it shoots back down thats when i get heat- obviously the t-stat finally opened up to allow coolant in for heat.

Checked coolant level its fine
Replaced radiator, water pump, t-stat- radiator cap, replaced upper hose and 2 little hoses by the throttle body they were cracked. also i replaced the ect(2 wire). I suspect onlything either would be t-stat bad again or lower radiator hose for some reason i dont know lol.

Problem has reoccured and went away alittle bit after the t-stat was replaced.

Any ideas??

 

[masho95]

Seems like the fan it going on at the right times to cool it down, when the gauge goes down to the "L". Have you checked out the ECT sensor? You've already replaced the thermostat.

 

[EZ4U2ENVY]

but if i drive above 45 mph the fans cut off right.... so in that theory i have been driving on the highway at 65-85 mph and still the gauge is hot and no heat as well until it drops down again- i rule fans out of that.....

 

[shobikes]

Did the new t-stat have the "jiggler valves?" SOunds like you've got an air pocket in the system somewhere which would give the indications you describe - particularly that of the guage going to very hot, then suddenly dropping to low in the range - that would be when the coolant flashes to steam around the temp sender...just a thought.

The new t-stat I got didn't have the valves - I drilled a 5/64" hole at the "top" of its ****** to bleed any air off.

 

[sdpatt]

shobikes:
Sounds like you've got an air pocket in the system...

... or a spastic thermostat. What brand and model did you install?

 

[SHOZ123]

Well if your system is full of coolant and the coolant is anything above ambient you should get heat. The fact that the heat is cycling means the coolant is in the heater core only sporadically and then is replaced by air which quickly cools resulting in no heat. The t-stat has nothing to do with coolant going through the core. You do not have your system properly filled.

 

[Off Road SHO]

Coolant is pumped through the engine block, heads and heater coils at all times as long as the engine is running. This constant flow is what eventually heats up the thermostat, which starts to open up and let SOME of the coolant get sent through the radiator.

Sounds like your baby needs a good burp.

Tom

 

[EZ4U2ENVY]

Well after a full day knocking my head on the hood- its finally fixed. I went ahead and replaced the t-stat with a better one with jiggle valves- so now theres no air in the system and its full of coolant. I get heat now and the temp guage is working beautifully and the fans come on when they suppose to... its all good now. Thanx for help and suggestions you guys are the best. Next project is wheel bearings.