"Overheating"

[Okin DaVanh]

This is just 1 of the 2 threads I found: viewtopic.php?f=11&t=19329&p=217160&hilit=overflow+spilling#p217160)



Car/motor: 96 EJ25





Scenario:
I'll start the car and begin to drive to what has been normal temp for me ( for the past 2 months since I bought it and had NO) issues) which has been just above the 1/4 mark. Continue driving at a normal rate of speed etc... things appear Ok. After about 15-20 mins of driving the car, It comes up to mid level and creeps towards the overheat level indicator, but won't go into overheat just yet. Pull over, and the weep hole on the overflow tank, starts spitting up antifreeze and the radiator is empty. Fill it back up, burp it. With the system burped, radiator cap on, overflow tank on the "full" mark and car running at idle with NO signs of overheating. I'll drive it for awhile. And after a little while driving the car, it looks like the gauge creeps up a hair, then when the pedal is released.... drops down. Hoses stay soft, but both are hot.


Now my Hypothesis :smt002 Waterpump is junk.

*Edit*
Swapped:
Thermostat/Gasket and Waterpump/Gasket, Same results. On 2/5 I changed the radiator and it improved, but after getting off the highway and slowing down, it starts to go up, but doesn't overheat.

[tylerkroh]

ya know im just spit ballin here but have you checked the radiator cap? I dont think its the water pump because i dont think it would cause the fluid to be pushed into your overflow and have the lines become unpressurized, i also wouldnt jump at the headgasket until you look for leaks all around and if it is leaking into the cylinders you would most likely cause a miss in that cylinder(i had an s10 with this problem),the thermostat doesnt make sense to me either because to my knowledge the thermostat can cause overheating by not opening and also cause it to run cooler because its stuck open but i dont see how it would push it out of the radiator. These are just my thoughts and anyone can shut them down or argue them but i would check the cap because they have two holes in them, one lets the pressure of the system go into the overflow, and the other lets the vacuum, that is caused by the cooling down of the engine, pull the coolant back into the radiator. like i said i dont want to tell you that the cap is your problem or the other things you mentioned aren't the problem i figured i would just leave my thoughts.

edit: Now that i think about this a little it could actually be your headgasket, because if its a small hole it can be pumping pressure into your coolant but it might not be big enough to allow enough coolant into the cylinder to cause a miss.

[Okin DaVanh]

Headgaskets were done in August. A month and a half before I picked up the car and with the revised gaskets from Subaru. Both heads were sent out and checked too. I did change the cap, I'm going to swap back to the old 1 again and see what happens.

[Reason]

I would check the head bolts to see if they are torqued to spec. I had an over heat issue and there was one bolt not correct. Ever since then I haven't had a problem.

1. Burp system (did you do it with the front end jacked up? Also when I "burp" the system I keep track and add more coolant every 100 miles till I don't need it. I also release any built up pressure at the pressure release of the left side of the radiator)

2. Swap that rad cap for shits, make sure coolant is filled.

3. check torque on head bolts, don't over tighten, just check.

4. check weephole on water pump

5. swap thermostat

6. do a compression test or a leakdown test

7. headgaskets are bad (replace)

8. heads are warped or the HG surface is not good

9. from there what is the car worth to you?

This is the order I would look into things.

[httrdd]

Yea if headgaskets were done (correctly) then i would assume thermostat. It my just be faulty. Also if it is not the thermostat and you continue to get air in some where it would have to be in a high place, like heater core or rad cap.

[Reason]

I didn't even think of the heater core, like TJ said that could be a possiblity too.

[Okin DaVanh]

I would check the head bolts to see if they are torqued to spec. I had an over heat issue and there was one bolt not correct. Ever since then I haven't had a problem.

3. check torque on head bolts, don't over tighten, just check.

This is the only thing I didn't check was this, there are no other signs of leakage from the heads or block as I put a cardboard sheet under it last night.
Everything else on that list has already been checked as I've worked on cars before.... Subarus too.

Yea if headgaskets were done (correctly) then i would assume thermostat. It my just be faulty. Also if it is not the thermostat and you continue to get air in some where it would have to be in a high place, like heater core or rad cap.

As much as I've been reading so far, if it were a faulty thermo, it should have shown issues from the start, but that's not to say that this 1 might be going/gone bad. Guess I'll start throwing parts at it. Sucks, because after $20 (yep, that's all I'm giving it) I'm going to call it a wrap. Take my personal stuff out, and get rid of it.

[Reason]

Well you are asking for help, so all options need to be explored. We all work on cars, yet we are still here asking questions and looking for help

[httrdd]

Damn man 20 bucks. At least try the thermostat and the rad cap. Cheap fix and you can eliminate those as suspects. I know you know, but if you dont go OEM ONLY!

[Dead91silvia]

I have had the same problems with a couple customers cars. One was literally after installing a new water pump and could not keep it from over heating.

I fixed it by driving the piss out of it for a block, then coming back to the shop. Did that a couple times. It burped it like it needed. Didnt have a problem after that. It took me a ling time to get another customers L to burp after just a water pump.

The currant problem with my BD is a popped HG, but I expected it and the motor is coming out already. It could be a water pump, thermostat, rad cap, or air in the system... Typical temp's for the 2nd gen cars run right at mid gauge, if not a little lower

[Okin DaVanh]

[mshriver]

Sounds like the HGs were not done correctly if its pushing the coolant out of the radiator

[Okin DaVanh]

***Update ***
Opened the hood, took of radiator cap (didnt replace with my original yet)
Loosened bleeder screw
Popped off overflow tank cap
Filled all to their respective levels.
Started car, ran for a little while until fans (yes, both would come on intermittently) and topped off as needed.
Closed/capped everything
Went for a drive. Same thing.
Hoses soft, radiator cap cold and coolant spilling out of overflow.
I crack the bleeder screw, Hot steam. Radiator cap still cold.
Took the bleeder cap clear off. Steam/ cool to the touch radiator cap and overflow tank overflows when I try to remove the cap for the radiator.
Car is NOT overheating until I try to drive it. Even without the radiator cap or bleeder screw on it while stationary.
Yes, I did do this for the 3rd time, jacked up in the front and the same thing. Again, NO pressure in the hoses and before and after the fans came on, there was plenty of heat.




There is no coolant in the oil, no white smoke etc...

I'm sure I'm forgetting to type something, as I just spent an hour outside and my hands are freezing as I type. I'll try to update this again, as I just found my old cap.

[httrdd]

Are you squeezing the bottom hose to get all of the air out? Squeeze the hose intemittently to force air out. I am guessing bottom hose warm and top hose cool?

[Okin DaVanh]

Nah, both hoses warm to the touch.

[httrdd]

Ok damn then you have an excess pressure problem if you are pouring into your overflow. Headgasket or like someone said head bolts.

[Reason]

OK so it's a flow problem, the t state must be stuck closed. Usually there's a fail safe and get stuck open.

[tylerkroh]

you can check your t stat by taking it out and suspending it in water and then bringing it to a boil, make sure you have a thermometer in the pot with it so you can check what temp it opens, if it doesnt open then replace it.

[Okin DaVanh]

ya know im just spit ballin here but have you checked the radiator cap?

I replaced the cap with the 1 that was originally on it and so far, things are OK.Took it for a ride to pick up my sister on backroads and stop and go traffic. It hasn't overflowed or overheated. I still have to change the waterpump tho. It's got the humming and no true pressure in the hoses.

[tylerkroh]

ya know im just spit ballin here but have you checked the radiator cap?

You're a freakin genius! Success!!.

I replaced the cap with the 1 that was originally on it and so far, things are OK.Took it for a ride to pick up my sister on backroads and stop and go traffic. It hasn't overflowed or overheated. I still have to change the waterpump tho. It's got the humming and no true pressure in the hoses. Cross your fingers, as I still have to check it again in the AM.

Cliff notes:
Swapped original radiator cap back on after filling and burping system.
Drove car 15miles round trip to pick up my sister.
Got home safely with no overheating or spillage.

just helpin a fellow member haha

[eekay]

Radiator cap! Hah! I'm glad everything seems to be working now.

[Okin DaVanh]

[Okin DaVanh]

Still doing the same thing.

[httrdd]

Yea i was hoping that was all, but it is never the end. Lol

[Reason]

OK so it's a flow problem, the t state must be stuck closed. Usually there's a fail safe and get stuck open.

remove the t stat

[Okin DaVanh]

Yeah, i'm on it but still can't get 1 yet. Just going to put the car away or keep playing with the "free" repairs til then.

[Reason]

No don't put another one in. Just take that one out, burp the system and see how it goes. It's FREE

[Okin DaVanh]

No don't put another one in. Just take that one out, burp the system and see how it goes. It's FREE

That's what I meant, but I would still have to buy another 1if it were the thermostat, as I wouldn't drive it like that.

[Reason]

With no thermostat in, it will just take a little longer to warm up. It won't damage the car in anyway. Do it and find out if its the issue.

[d1giPhux]

Any possibility that your thermostat is partially plugged? You could test this by using a infra-red laser thermometer. I know.. if you don't have one, its a bit of a hassle. However, if the car overheats, and you have access to one.. try testing various areas of the radiator after the overheat occurs. See if any parts are colders / hotter than others. Its possible that if you didn't flush the radiator much (who does??) that its partially clogged or something along those lines.

Next test in line would be the boiling water thermostat test.

Also, are your cooling fans working?

Hope you can figure this out..