[RESOLVED] coolant system wont hold pressure. please HELP

[southrneclipser]

OK my 95 eclipse 420a is overheating and idk what to do with it anymore. i pulled out the engine and tranny to do some maintainance. Its got:
- new water pump
-new rad
-stock fans (work fine)
-70/30 coolant mix
-new thermostat
-16 psi rad cap

It ran fine for about a week and now the water temp has jumped up to about 125-135 degrees. This was driving with hood off by the way. It usually stays around 95 degrees. It also stopped putting out heat from the vents. When its off steam is escaping from the overflow hose so it wont hold pressure. Could there be a bubble in the heater core thats not letting coolant circulate through it? If so wy would it be releasing pressure from the overflow hose. This is my DD to school so any help is greatly appreciated.

by the way one of the hoses is disconnected from the a/c compressore. i didn't think that mattered but i figured i'd let you all know.

 

[Dewayne Waldron]

Check to see if your coolant is discolered or has any particles floating around in it. Then check your oil and see if it is over limit or smells like coolant. If so it is probably your head gasket. especially since you have changed the thermostat already.

 

[96eclipzGsT]

Could be the radiator cap. Rent a leak down tester from autozone and see what it will hold.

 

[johnmarines]

+ on headgasket

 

[bigdukk2]

check that radiator cap.. if steam is comin out of your overflow.. its leakin outta your pressure cap... they go bad often.. replace and check... and your heater will only work if you can pressurize the system.. but to let you konw.. your engine should run about 180, not 90... just thought i'd let you know.. unless you mean Celcius..

and yes.. there could be an air bubble in the heater core.. the process to get it out is called "Burping" the radiator.. you need to set your heat to FULL BORE hot.. and open you cap.. and leave it off.. and let it run till its hot... it will overflow a crap load at first.. and then all of a sudden it will "burp" you'll know this when you see it... then it will be rather empty so have a bottle of water on hand to refill it quickly until its full.. and violla....burped...

 

[rEclipserGST]

Is the bottom radiator hose warm in comparison to the top radiator hose? Did you bleed the system? Did you do a leak down test? Have you replaced the Coolant Temp Sensor (ETS)? Have you replaced the old hoses? Replace head gasket. If all fails, Blue Devil ($60 at NAPA auto parts store).

 

[96eclipzGsT]

Just because it is boiling out of the overflow doesn't necessarily mean its a headgasket. It could be many of the following

thermostat
air in the system
bad radiator cap
warped radiator seat (for cap)
plugged up radiator/block
dirt caked in the front of the radiator not allowing it to cool

The normal temp of the car runs between 160-195 depending on what degree thermostat you have. Stock I believe is 195.

 

[southrneclipser]

its not my head gasket. and i have a new radiator cap. and its not boiling out of the overflow. its letting pressure (air) out. What would a leak down test do for me if i already know its not holding pressure. and the top and bottom radiator hoses feel the same temp to the hand. and by the way i origonally meant it normally runs at 190 degrees not 90

 

[JEFFREYCASTGSX]

If it stopped blowing heat from the vents, then there is a blockage(or a bad water pump, yes i know its new) in the system, and then more likely from the heater core(maybe). First bypass the heater core, disconnect both hoses from the firewall and connect them together, go drive it and if it doesnt heat up then the heater core is clogged. If it still does it then heater core is not the culprit. Another thing to do while your at it, disconnect the top water(while the car is cold) hose, and start the car, if water does not spew out then the water pump IS BAD(since you say its spewing air out it might be the water pump too). But first start out with checking the water pump and go from there.

 

[96eclipzGsT]

its not my head gasket. and i have a new radiator cap. and its not boiling out of the overflow. its letting pressure (air) out. What would a leak down test do for me if i already know its not holding pressure. and the top and bottom radiator hoses feel the same temp to the hand. and by the way i origonally meant it normally runs at 190 degrees not 90

I don't think it will just let steam out of the overflow unless there is absolutely no coolant in it. Even if the heater core was plugged up it won't make the car run hot and if the HC was leaking your floorboard would be wet.

Fill it full of water and let it warm up to operating temperature and check for leaks. Also check oil to see if it is milky looking.

 

[JEFFREYCASTGSX]

I don't think it will just let steam out of the overflow unless there is absolutely no coolant in it. Even if the heater core was plugged up it won't make the car run hot and if the HC was leaking your floorboard would be wet.

Fill it full of water and let it warm up to operating temperature and check for leaks. Also check oil to see if it is milky looking.

The heater core WILL cause it to overheat, it doesnt have to leak to be bad. If the vents arent hot when the A/C is set to hot, then there is no coolant passing through the heater core, meaning its either clogged, or there is something else(somewhere else) clogged, or the water pump is done(hmm air?).

 

[southrneclipser]

when i was by passing the heater core as JEFFERYCASTGSX recommended i noticed the hoses were loose where they connect to the engine from the HC. Those hoses were all rotted out so i replaced them and viola. No more overheating. So Jeffrey Cast, thank you for the help.

 

[JEFFREYCASTGSX]

when i was by passing the heater core as JEFFERYCASTGSX recommended i noticed the hoses were loose where they connect to the engine from the HC. Those hoses were all rotted out so i replaced them and viola. No more overheating. So Jeffrey Cast, thank you for the help.

Anytime.