Hello

I have a 2000 s type that is overheating, thermostat, water pump, water control valve have all been replaced. New fluid and bleed. 180 degree thermostat put in, engine temp is between 210-220 with heater on, heater turned off it over heats. AC was not working after replacing water control valve AC worked for about 15 min, once engine temp reach 200 no more AC has not worked since???? Just hot air. After replacing water pump no change in temp. I have my car connected to a computer, coolant temp is 200-225 but the car gage is on normal level. Once I stop the car fluid boils out the reservoir. Prior the changing water pump radiator was cool to the rich after driving as if there was no circulation after replacing water pump radiator is hot after driving. What else could be the problem.




Thanks
Ben

 

OK, went lurking and found you are in the US of A, which might help others, as these cars are different RHD and LHD.

Are the radiators fan/s coming on??

Changing that DCCV unit disturbs a lot of stuff, so that area would be worth a quiet look at.

Air in the system can/is a mongrel to bleed out. Our RHD are self bleeding, and still have issues when that tap is replaced, and you have opened a lot more of the system than just the tap area. Water pump, thermostat, etc.

Others in your market may have other suggestions, but I reckon its still got air in it.

 

Hi Ben,

Does the engine overheat at all speeds, or just when driving slowly or stopped? Can you hear the electric fan running?

On my '02 V6, when the electric fan quit, the coolant temp would start climbing at speeds under 35 mph or so due to the lack of airflow through the radiator. At higher speeds all was fine due to ram airflow, but the coolant temp would climb back up as soon as I slowed down again.

 

Hello

Yes it will overheat at all speeds, the faster I drive the faster it overheats. seems to run best at about 55-60 2000 rpm. for this reason I was thinking the water pump was going out. but no luck. also my ac only works when the engine is cool. once i get to 150 range ac slowly goes out. Yes the fan is running once the engine temp gets to 225+ fan continues to run after engine is off until cooled down.

What is the optimal engine temp the 2000 s type should run at?

Air in the system is something I have check, I have looked into that problem several time and system seems to be air free constant flow from the both bleeder valves, reservoir tank, and by thermostat.

Thank you for the ideas and suggestions thus far still working on it.


Ben

 

Is it possible to install the thermostat backwards? Haven't messed with mine so I really don't know. Or maybe the new one is bad from stock?

 

New thermostat was installed the same as old one but I still double checked just to make sure the old one was not put in backwards two years ago when I replaced the thermostat and water pump back than. I tested the thermostat before instate and it opens fully at 180 degrees.

 

If you had replaced the water pump and thermostat and the fans are running I would drain the system and do a flush. After that is done drain ALL the flush and refill with coolant. When refilling the system squeeze the upper hose gently to get all the air out of the system close it up and start the car then shut it down. When cool check the level again and squeeze the top hose to be sure all the air is out and refill if necessary.

 

For giggles, I fired up my scanner and watched the coolant temp on my '02 V6 this afternoon. It ran around 215-225 in mixed driving.

You previously mentioned your car would overheat unless you ran the heater. You also mentioned AC problems. That makes me question the airflow through the radiator and condensor. Maybe the problem is as simple as a plastic bag stuck on the face of the radiator. Blocked airflow would affect both the cooling and the AC.

Others have mentioned the need for careful bleeding of the cooling system. That would be a good idea to check. On my car, however, it didn't matter. I've done some cooling system maintenance in the past and was too lazy/stubborn to bleed the system after replacing some hoses. I figured I'd just keep an eye on the coolant temp with my scanner. I had no issues whatsoever with overheating. The only thing I noticed was the heater was slightly erratic at first, but that settled down within about ten minutes. This was on three different occasions. Your mileage may vary...

 

Ben,

I reread your original post. You've got a long list of parts that were changed, but what started this whole sequence of events? Was it originally an overheating problem out of the blue? Or was it something like no heat so the DCCV was changed, after which the engine overheating started? I'm just trying to do a sleuthing and find the root cause.

Re: my thoughts about inadequate airflow through the radiator and condenser. Here's a quick test. With the engine running and warm enough so the fan is commanded on, put a piece of paper across the grill. There should be enough airflow to hold the paper in place.

 

​​​​​​I have a 02 jaguar s type 3.0 My heat didn't work in it so I replaced the thurmostat and it said that I had a miss in cylinder 3 so we fixed all of that and now my car overheats. What could be the problem. And I talked with a mechanic and he said that It doesn't sound like it's a bad head gasket so I'm wondering what the problem could be with it