Cooling problem in EJ25D

[L.Michael]

I first noticed that at operating temperature, and at idle, there's no heat blowing through the vents. Then Yesterday, it started overheating. Most the time bringing the engine RPMs up to 3000 would fix it, But sometimes it wouldn't, and it would start boiling over. Pressure built-up and it would overfilled the reservoir. Replacing the thermostat made complete sense.

So new thermostat, gasket, and coolant seemed to fix the problem. Was blowing consistent heat, no overheating problems, everything seemed to be alright.

After a long test drive, i pulled up to the house, And it stopped going heat again.. No strange noises coming from it giving me the idea that the water pump has failed.

Is there some electric valve or a solenoid that could have failed??

[L.Michael]

What i'm maybe thinking, is that where the thermostat is located, and a low temperature outside, is resulting in a openin problem with the thermostat.. This is my first winter with her.

There was a little bit of air getting in from the overflow hose not being clamped tight, which is now rectified. But from having no heat at idle yesterday at -25, to havin abundant heat at -14 today, I am definitely leaning towards insulating the thermostat housing.

[L.Michael]

Well,

I have concluded that it must be the head gasket failing. Its the ebay set, which isn't the proper steel gasket. I'm under this conclusion because the air is building up pressure, and it must be coming from somewhere! When I get all the air out of the system, then start & run it, I'll have more air.

The reservoir does have a scent of exhaust, but the exhaust itself doesn't have a scent of burning coolant, and the oil has no signs of mixture. The only thing is the air in the cooling system, and thats all I'm going by.. The previous engine had failed with the original gasket. There was a lot of water in the exhaust then.

[L.Michael]

viewtopic.php?f=11&t=26297 (http://www.sl-i.net/FORUM/viewtopic.php?f=11&t=26297)

[Dead91silvia]

If it's over heating, 95% of the time, its the head gaskets.

Always use OEM headgaskets, they seem to last a lot longer and they are not too much.

If you are finding your outside temps at or below freezing, I would invest in a Block heater from Subaru. They are pretty cheap and easy to install. That will help your motor out a lot in the super cold weather.

[L.Michael]

I had to install a block heater into the replacement block, that was done before it snowed. It works fine, and have been plugging it in regularly. i did have an issue with it prior to all this with the coolant freezing in the rad one day. was coming out all slushy, I hadn't put on a winter front yet at that time, which might have kick started a chain reaction? But the thermostat was something i should have replaced in the summer.

The thermostat was noticeably going over the last couple weeks, but it caused an overheat in the system on Thursday. I replaced it that evening, but have been having issues with gasses in the coolant since. I can only conclude that the overheating caused the HG failure. An unfortunate situation for me, as it probably would have been an easy fix had I changed the thermostat prior to the overheating..

C'est la vie, I suppose.

[L.Michael]

Oh,

the original plug in place where the block heater goes was a PINA to get out! Perhaps a hex key in an impact would have been the easier way, but I didn't have one that big. It was heating it with a torch, and much effort with an allen key wrench w/ cheater bar...

[L.Michael]

Just to update this thread. I had removed the engine from the bay without removing any of the intake parts. Pulley drives, air intake, and wires/hoses connected from engine that wouldn't let the engine leave the bay.

Impact wrenches sure make a quick job out of the cam and drive pulleys! Never did find a proper tool, other than an old belt, to loosen these. Heads came off easily, the graphite gaskets were like goo and shit. Had to spend some time with a razor blade and cleaner to clean the block's mating surface.

Heads went in to the shop, all was well, as well with 4 & 5 thousandths taken off the surface. $300 bill there with the new MLS HG's, and I was set to reinstall everything. Never replaced any of the other gaskets, which may mean that the intake might need replacing here real soon..

New water pump as well, have been experiencing no problems at all now. There is the drop in mileage however, which is why I'm concluding the intake gasket may need to be replaced..

http://i1066.photobucket.com/albums/u41 ... 2055ab.jpg (http://i1066.photobucket.com/albums/u413/LMHradecki/IMG_0842_zps232055ab.jpg)
http://i1066.photobucket.com/albums/u41 ... 2851e1.jpg (http://i1066.photobucket.com/albums/u413/LMHradecki/IMG_0843_zps9e2851e1.jpg)