S80 Thermostat, where is it!?
 

Most cars have it at the end of the top hose from the radiator. But it doesnt look like that connecting peice of my S80 can hold a t-stat. Nor would the one I ordered fit in it.[sm=smiley24.gif]

RE: S80 Thermostat, where is it!?
 

If it isn't in the upper hose it is under the timing cover mounted in an aluminum block. The coolant temp sensor is in the same block.

Back from the dead!!!

I have a question before deciding if I'm going to do this myself, or have the shop do this job.

I have a 2000 S80 2.9. Just got home 20 minutes ago. Car just overheated. Now I was driving the car "very spirited" for about 10 minutes or so. I do push the car hard pretty often (I've got a lead foot) and NEVER has it gone past the half way mark. Not even a tick and I've driven the car hard in 103 degree heat with the A/C on. Took me about an hour to drive 2 miles home (waiting for it to cool off)

Didn't think about it at the time but I need to test if it is the waterpump or the thermostat. Only way I know to do that is run the heater, and if it starts blowing cold then there is no circulation (waterpump)

Now the waterpump was replaced when the timing belt was changed (about 8K miles ago). Doubt it's that.

Back to the thermostat and WHERE IS IT???

I need to know if mine is behind the timing cover. I'm pretty sure it is as the top radiator hose goes to a metal piece that goes from a tube shape to a rectangle shape that bolts to the head. I'd assume there's not thermostat under there. Got a feeling it's behind the timing cover. Unfortunately I did not change the thermostat while doing the timing belt. Didn't think about it.

If it is does the motor mounts need to be unbolted and the engine lifted with a jack to get to it?

I basically have NO tools anymore. I have a friend who can loan me a basic socket and wrenches. What tools would I need to do this job?

Thank you in advance,
Jonathan

I had a similar problem shortly after my timing belt was replaced (Within 30K miles) where the car started to intermittingly overheat, turned out to be the water pump impeller came lose from the water pump shaft. I had replaced the thermostat and the radiator before going into the water pump. Found the impeller was plastic on a steel water pump spline. The plastic impeller spline had worn out and was half way rotating on the metal pump spline thus the intermitting overheating problem. I don't recall which water pump was installed when the timing belt was replaced, but it was a German manufactured pump, which I would not have expected. Replaced the pump with a metal impeller pump and re-did the timing belt myself because I was so pissed at the shop that put a plastic impeller water pump in my car. Sometimes its better to do things yourself.

Well on the way to work today I ran the heat and it continued to blow hot. Im going with thermostat as its alot easier than a new waterpump. Car overheated in proximately 12 minutes at 92 degree ambient temp.

I would do the same. The thermostat is the easiest and least expensive to change out. If you get heat with the heater on I would not think that the thermostat is the problem...Your problem sure does sound like the condition I had, a slipping water pump impeller. The impelller spline was not toally stripped it just did not circulate the volume of water needed under heavy engine load conditions. By the way don't be too surprised at how long the engine takes to burp all of the air out of the system, in my case it took many hot to cold cycles with adding about another 1/2 gallon in small increments each time before it remained full in the overflow tank. Good luck... I am interested in knowing if the thermostat fixes your problem so post your fix....