Officially Stumped!!

[Jrock11]

Ok so my buddy has 98 eclipse like me, a couple days ago his a/c belt took a dive, he then noticed a couple days after his belt went that his car started overheating. Knowing that the a/c belt didn't have anything to do with the cooling we knew it had to be something simple. We pressured tested to check for leaks but no leaks what so ever. We then installed a new fail safe thermostat and radiator cap....nothing. The radiator was replaced not too long ago so we went ahead and replaced the water pump and coolant....nothing. So he just said F%$# it and bought a 2 rail mishimoto radiator and installed it....nothing. The car only starts to get hot when you start boosting if you drive it easy it'll be fine but he only boosts about 10 psi and then as soon as puts it in nuetral the temperatur gauge goes back down to the middle. Oh ya and both fans kick on. Pleeeeease some suggestions

 

[TurboJimbo]

Could be that the headgasket has gone

 

[boosted_ego6985]

When filling the car back up with coolant, did you turn the heat on all the way to open the core up and get the coolant into it as well? I have heard that when refilling with coolant to turn your heat on fully and fill the car with coolant then start the car with the radiator cap off and let it cycle down then continue to add coolant till its full and lock the cap down. Keep in mind to only run the car with the cap off no more then about 5 mins otherwise youll start getting hot coolant spit at you once the thermostat opens up . Other then that I would have to agree ^^ maybe it is the head gasket starting to go out. Good luck

 

[Jrock11]

Ya we had the heater on and everything and ya i'm worried about the headgasket as well. I don't see anything coming from the head gasket and he isn't losing any coolant. It's also a newly rebuilt motor with only a thousand miles on it he's been driving for a month now and it was fine until his belt went out. I just hope something wasn't improperly installed ya know

 

[boosted_ego6985]

If it's freshly rebuilt something may not have gotten tightened on the head like needs to be. I'm hoping that you guys replaced the head gasket when it got rebuilt but I trust you did. If not then BIG mistake. I would also double check and make sure the thermostat was put in facing the correct position. Sounds dumb but youd be surprised how many people can screw that up myself included when a few brews are involved . Other then that I'd say the HG man. Even though you may not be loosing coolant you can have a bad one because on the neon I had it blew out on the exhaust side so no coolant mixing with water or anything and no losing coolant but still causing overheating. Hope that's not the case but ya might wanna be considering it. Good luck

 

[Jrock11]

Ya anything is possible to happen but oh ya we did replace the gasket we didn't have that many brewskies at the time haha but alright man thanks for the help well appreciated

 

[boosted_ego6985]

No prob let us know how it goes.

 

[El Cuervo]

Before deciding that the hg is fcked, go in and re-torque your headstuds. I bet they are loose. This seems to be a problem and sometimes miss diagnosed thinking that the hg is at fault but sometimes its just loose head studs. Give it a try.

 

[Jrock11]

Ok so we found out that it is the head gasket and thanks for the advice were gonna re-torque the head pretty sure that will work

 

[boosted_ego6985]

Glad to see you guys got it figured out. Torque them back down to spec and see if that works. If it starts running hot again then you may have to replace the HG yet again from it being damaged. Hopefully that doesn't happen to ya. Good luck with it