Burning Oil, Blown Head Gasket, Front drive shaft boots
My car was burning oil (~qt per 1000 miles).
Also it showed the symptoms of a blown head gasket (temperature spike, relieved by
revving engine and/or putting heater on).
There is oil all over each side of the engine on the frame. There is no clear source.
Also the front drive axle boots are broken.
I have the heads off. Should I be worried about the valve stems or anything else other
than the head gasket, cam seal and valve cover gasket?
Some pictures that might be helpful
Yes...get rebuilt axles and don't mess around with the grease...on the head...set off a weekend and disassemble clean the sealing surfaces and take it to a machine shop for a face-off~ replace and torque to spec~
...as far as your oil consumption could be a bad PCV valve (cheap to replace) or just be a worn engine~
So I should definitely remove the valve springs and replace associated seals? What is the indicator that this is needed? Its a pretty expensive tool to get the springs on and off. What are the signs if the engine is simply worn? There was some black hard crusty gunk on a few of the piston heads. A few of the valves were a little white.
take your top end rebuild (actually side-rebuild) just as far as your budget will afford...as being perhaps an amateur might like to take 'er to a shop that has your budget in mind~ but if financial concerns and a spirit of adventure dominates, take that head off of there and replace the gasket (if this is the problem here)~
the valves could be inspected to see if burnt or leakin'...then take the springs and valves off, or just exchange the buggered head for a fresh rebuild~
If you're going the whole nine yards will have the head hot-tanked and machined, the valves recut, or ground, valve guides replaced...whatever your budget will allow~
...you're silent...that's kinda how I feel about things but....you know a big heavy block like the Americans like to produce is like a big dinosaur goin' down the highway, has big brakes and a big attitude...Subaru's are more like a delicate instument...like with the delicacy or a microscope...Not to be heavy handed, but merrily tackle everything with the 4wd adventure~...the unique H design forces the center of gravity DOWN where it belongs, for easier curves and not-so- much afterthoughts on the handling as a result....a good car..you've either fallen in love with the intricacies or want to buy a big a$$ 440~
You should also get new spark plug seals for the heads, but I would not say you need to tear down the valves or anything like that. I would, however, have the heads checked by a machinist and planed if they are out of spec, as they can warp due to overheating. If you didn't overheat the car though, you are likely fine. I see you didn't pull the motor, but usually people pull the motor to do this work and do the rear main seal while they are at it.
The PCV Valve was bad. So hopefully this is the source of the oil consumption. The temperature gauge read high many times (then would return to normal), but I am not sure this constitutes actual overheating.It always had antifreeze in it. I polished the Head using a block and 400 then 600 grit sandpaper. I will check and see if in spec. (0.002 in max). I do have new spark plug seals. Jeff, why wouldn't you tear down the valves?
Honestly, I'm not sure how bad the motor has to overheat to actually warp the heads, but my hope has been that if you catch it heating up and stop before the car itself dies from it, you avoid that damage. Regarding the valves, Subaru valves almost never have issues unless the timing belt snaps and they hit the pistons, or there's some sort of other debris that they hit. Especially for a non turbo motor, the valves last a long while before needing any sort of work.
choulesb, I usually look at the bottom of the hood is a kind of record of the overheats~
would spend an afternoon at the pickNpull and chose non-burnt components to do the reconstruction~
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