2.2 Subaru Blowing Coolant

[Wildthings]

I have a junk yard 2.2 Subaru that came out of what looked to be a very well maintained car that took a tree across the passenger compartment. It started easy and sounded fine when I went to look at it and all the fluids on the car were at their correct levels. I installed it in my 91 Vanagon and it seemed to run just fine, but after maybe only 1000 miles I noticed that coolant was spewing from the refill tank. Since we were on the road, we dumped in some Subaru Cooling Conditioner and kept driving, at first this seemed to have stopped the problem but after another couple of tanks of fuel the problem reoccurred and was now noticeably worse. I just started checking the coolant after any long down hill grade, adding about a half gallon each 50 miles or so, filling the pressure tank but not the refill tank.

Once we got where we were going I just parked the rig until yesterday, when I went at removing the heads. The only thing I noticed in removing the heads was that the head bolts were extremely tight, I actually put on a face mast because I was afraid I might blow up the head of my 1/2" breaker bar getting them loose. I am sure it required in excess of 500 ft*lbs to break the worst of them free. When I pulled the bolts it appeared the threads had not been lubricated on installation, but there were no signs that the threads had pulled.

On pulling the heads I could not determine where on the sealing rings the leak might have been occurring, as the gaskets looked fine while obviously having a goodly number of miles on them. I can see nothing in the head sealing surface that would indicate a leak either. I guess my question is, is it normal to not be able to see signs of a combustion leak on a Subaru engine? Any suggestions on a course of action?

Thanks

[alaskadan]

Granted the engine in my van is 2.5 but when it blew a head gasket the bad spot took a keen eye to spot. Though you could tell which cylinder was affected easily. Are you able to at least see which cylinder it was?

[markswagen]

head gasket time, maybe the heads need to be resurfaced.
i have a customer who's van in 20k miles, filled to expansion tank 3 times, thousands of miles apart, it drove from san diego to bellingham, near san fransisco on the way back it did it, once, the rest of the way no problems, once it was was cooled down, refilled and bled out, a few months later it did it again, the last time it did it, just as it was sold to a new owner, heads were pulled this time, and found the original gasket on the passenger side had failed, closer inspection revealed that the head on that side was not flat, new reconditioned head were fitted, and 6star gaskets, and it's been fine since.
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markswagen {mobile mechanic} san diego area all early VW's cared for.

619 201 0310

[levi]

Check your blue (black?) high pressure cap before assuming it's head gasket time.
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[alaskadan]

Yep, six star gaskets too. I resurfaced my heads myself. Used wet dry sand paper glued to a piece of thick glass. WD 40 as a lube and 1000 short strokes back and forth. 100 at a time, clean off sand paper with WD and a rolling motion with paper towels. Re lube, repeat. It was a few more than 1000 but doing it that way helped mentally to achieve doable goals over and over. Only tried this after reading up on it and found it to be very common practice and the results were very good. Nice thing about the suby heads is they fit on one sheet of sandpaper with room for the short strokes.

[hogan029]

I just went through this. +1 on the pressure tank cap. It's a process of elimination. Mine was spewing out coolant out of the overflow tank and I didnt notice as it all burned off on the exhaust. Might as well get the heads machined and a good quality multi steel head gasket replaced. The torque sequence is key on the reinstall.

[dlb154]

[alaskadan]

You tube has a number of diy head resurface vids that were really helpful. The
hard part is having that really flat surface. A sink cutout from a granite countertop would be ideal, scrap at a stone countertop shop. Or a piece of 3/8 to 1/2" glass. I used some 3m heavy duty spray carpet adhesive to attach the sand paper. 400 grit wet dry. Sorry I didn't really save any one link for this project.

[Wildthings]

The block end up not being level in the #4 cylinder area, with the cylinder being several thousands lower than the rest of the block surface.

Strangely with everything back together the engine was blowing coolant worse than before, there was essentially no flow through the block so localized boiling was occurring within just a couple of minutes of a cold start. Pretty puzzled as to what might be going on. In trying to figure this out I noticed that the problem began to abate instantly when the heater valve was opened and disappeared total when the heater valve was opened over 1/2 way, the temperature gauge dropping from above the light to below the light in 10 seconds or so. Really had a hard time imagining the heater bypass which had worked fine for 100K miles to all of the sudden stop working, but since I had no better ideas, I decided to pull and inspect the "H" style bypass I had built, just a shunt between the two heater hoses that was necked down to a 1/4" opening. On removing the short section of hose that makes up the center of the "H" I was surprised that I could not see through it at all, so I got a thin punch and probed at it and out popped this.

Don't know what it is, but it is a piece of hard plastic and fits nicely into the 1/4" hose I had used for an orifice thereby blocking it 100%. I believe that the piece had likely been in the water jacket of the replacement engine and it eventually found its way to orifice in the heater bypass.

With the bypass cleared and functioning correctly, I was able to drive up a 6% grade with a 3000' elevation gain at 100°F with no signs of overheating or coolant loss. Yeah!!!

[chompy]

I wrote this whole thing out and then read your last post.

Good job man! Not exactly something you would expect to find...

Edit: Alaskadans method is the way to resurface Subaru heads. Although I've ended in 600 grit and had it work great.
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'81 Westfalia Subaru EJ22
Manual Transmission

[alaskadan]

Wow, good catch. It's nice to find the smoking gun.

[Abscate]

You might think that was root cause but in fact your Vanagon was crying over having a Soobie in it.....
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.ssS!

[Wildthings]

[Abscate]

[Zeitgeist 13]

Blowing coolant is a feature
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'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
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[wesitarz]

A chemical test for HCs in the coolant would have been useful before removing the heads.

[wesitarz]

[Wildthings]