cdupont03

iTrader: (31)

Alright so my thermostat is good, no leaks anywear, flushed radiator twice. But I am still overheating. Coolant hoses seem to be not as hard when running as they should be. Do I need a new water pump and wheres a good place to get one online if so.

evo542

either the water pump is bad (most likely) or you still might have air trapped in the system (not too likely). How much does the dealer want for a new pump?

elhalisf

iTrader: (171)

part number MD979313 MSRP $165.63

EiEVO

iTrader: (9)

Well these are your possibilities being you have already replaced your t-stat and you state that it is opening and working propperly.

1.) Leaking Headgasket
2.) Air in the system.

Why do i say its not your waterpump? Well first off its not leaking or you would have stated otherwise, its not making any growling/grinding/humming noise. If it was your waterpump it would be doing one or more of the reasons i listed.

Trust me i deal with this exact type of work ever single day. How hot is it getting?
more than 215 F.? If so then i suggest you not drive it until it is fixed. Most cars dont run over 209 degrees F. My evo runs from 182 TO 192 and that from idle and under a hard load making a long pull.

Did you pull anything apart? Drain some fluid or how could it possibly have air in the system? Did you have to top the fluid off or put in a gallon or more of antifreeze?

I say you either need to go buy a "spill FREE" or borrow one... Or take it to a shop where they can propperly bleed the cooling system. When did it start to overheat? What were you doing and how long has it been overheating?

The spill free allows you to run your car with the radiator cap off. This way the system will have a way to breathe and it allows the air to go to the highest point when the engine is fully warmed up. When the thermostat opens up and the temp is at normal you then can push the long handle plug into the spill free and take it off without making a mess. Then put your radiator cap back on and your set.

EiEVO

iTrader: (9)

Oh yea, your local parts store should have a spill free setup. Should be $30.00 or close to it.

barneyb

Are your fans running?

Are you really sure the thermostat is opening and at the correct temperature? To be sure you need to pull and boil it while checking the temperature with a thermometer.

I've never heard of impeller failure on a Mitsu pump - maybe if you have some aftermarket pump this could happen. So, if you have a Mitsu pump and it is turning then I'd say it is pumping.

If the hoses don't feel as hard as normal then the pressure cap is bad. I checked the OEM cap on my car at 30k and it wouldn't hold pressure. I should have checked sooner. The life of radiator cap is about two years. However, even with a bad cap my car didn't overheat.

Flushing the radiator on a car this new is a waste of time. The radiator should still be clean. If you change antifreeze mixed with distilled water every 30k the radiator should aways be clean.

I used the technique listed in the service manual for getting the air out when refilling my radiator and it works. I didn't have any special funnel.

Finally, a blown HG acts like overheating. Gases of combustion are forced into the water jacket forcing the coolant into the jug. With a blown HG you will see boiling coolant in the jug and coolant on the ground.

cdupont03

iTrader: (31)

Alright I am pretty sure the t-stat is working properly. I replaced it cause it was my first thought and I checked the brand new one in boiling water. I had an aftermarket 1.3 cap and I decided to put OEM cap back on and still no help. Car is running at about 220 degrees. I can find no leaks, I bought a leak detector kit and found nothing. No water from exhaust, I pulled the plugs and noticed no water underneath. I dont seem to be losing any noticeable amount of water but the temp stays the same no matter the temp outside. The radiator seems to be pretty cool at the top while the water in the hoses is hot. And yes my fans are running.

cdupont03

iTrader: (31)

BTW slo boy racing water pump $150 for the EVO.

barneyb

Well, if the impeller was off the shaft it wouldn't pump at all. Test for this by pulling the stat again. Then refill and run the engine with the pressure cap off watching for circulating coolant.

cdupont03

iTrader: (31)

Thanks I will try that tomorrow. I decided to buy a compression tester and thankfully everything seems good. 180 on all cylinders. So I think blowen headgasket is out. Off topic I also bought a OBD II scanner pulling P0134 and P0171. Looks like its time for a new 02 sensors.