Intermittent Overheating

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valpaval15
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Intermittent Overheating

Post by valpaval15 » Mon Oct 19, 2015 9:25 pm

Background Info:

So There's a water hose under the intake on the passenger side of the motor that the PO didn't put a clamp on, I guess it built a lot of pressure and a lot of coolant leaked out onto the block. I put a clamp on it and no more leak, I also put some more water into the coolant tank and the overflow bottle. HGs were replaced less than 10k miles ago. Fans work. Water pump also replaced.

Problem:

Literally like 5 minutes after driving it the temp will start to climb (never let it overheat). I would just shut it off while moving and left the power on to let the fans blow. I'd then just roll start (yes it is manual swapped) it after the temp gauge went down. It takes maybe 1 or 2 shutdowns while moving and then I can go on my merry way and it wont heat up at all.

Questions:

Could it just be air in the system?
Did my thermostat happen to go bad at the same time?
What could be wrong?

MConte05
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Re: Intermittent Overheating

Post by MConte05 » Mon Oct 19, 2015 10:23 pm

So it had a leak, you fixed it, topped it off, now still slightly overheating?

Does sound like the system just needs to be burped, and you have an air pocket stuck if that is the case.

mike-tracy
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Re: Intermittent Overheating

Post by mike-tracy » Mon Oct 19, 2015 10:45 pm

What he said, plus I've had problems with non factory thermostats, and to a lesser degree (no pun intended!) A knock off radiator cap
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote:
Mon Jan 14, 2002 10:23 am
Wait....I'm confused now.

robertpaige
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Re: Intermittent Overheating

Post by robertpaige » Mon Oct 19, 2015 11:50 pm

Yeah. Sounds like you got an air bubble in the system.
Had more Legacy's than I know what to with...
Current: 92' SS

Legacy777
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Re: Intermittent Overheating

Post by Legacy777 » Tue Oct 20, 2015 5:45 pm

First thing's first, what year and model Legacy is this?

If it's a non-turbo there is a bleeder screw on the passenger side of the radiator that needs to be opened during filling so you get the air out of the system.

If you can provide some more details that will help in troubleshooting your problem.

Thanks
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

valpaval15
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Re: Intermittent Overheating

Post by valpaval15 » Tue Oct 20, 2015 6:26 pm

Oh well that's embarrassing, I thought I wrote down what car I had. It's a 1993 Legacy TW. What's weird is I did burp the system, maybe not well enough from the looks of it.

Legacy777
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Re: Intermittent Overheating

Post by Legacy777 » Wed Oct 21, 2015 6:22 pm

If you're running a stock radiator and cooling system the turbo radiator has a line that vents the radiator to relieve trapped air. These still can be a little challenging to burp, so you could try putting the car on an incline with the nose up.


Also, what brand thermostat are you using? If it's anything but a Subaru tstat that could cause you problems.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

valpaval15
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Re: Intermittent Overheating

Post by valpaval15 » Wed Oct 21, 2015 8:57 pm

I don't actually know because I haven't changed the thermostat, but good news. I brought it home while it was starting to heat up and i just opened the radiator cap enough for steam to come out, as soon as water started to come out I just closed the cap really quick.

Now it works beautifully again! Thanks guys for all the help. And what line were you referring to? I have the stock radiator but I never noticed any lines other than the upper and lower radiator hose as well as the hoses that go to the coolant tank (not the overflow tank).

Legacy777
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Re: Intermittent Overheating

Post by Legacy777 » Fri Oct 23, 2015 5:37 pm

The turbo radiator has a small coolant line just above the upper radiator hose that connects to the coolant expansion tank. Does yours have this?

And this is why I asked what model you have. The cooling system is different between the turbo and non-turbo engines. I am making an assuming that you have the stock radiator setup on the touring wagon, which was turbo.

In reading your last post, you mentioned you opened the radiator cap, was this opening the cap on the radiator or the coolant expansion tank?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

valpaval15
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Re: Intermittent Overheating

Post by valpaval15 » Sun Oct 25, 2015 10:03 am

The expansion tank cap, and it does have that line I just didn't know it was for that purpose. And yes it is the stock rad in my turbo wagon.

Legacy777
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Re: Intermittent Overheating

Post by Legacy777 » Sun Oct 25, 2015 11:42 pm

Ok, well hopefully it was just trapped air and you got it sorted out.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

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