Repeated cam seal failures? 09 Subaru Forester

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First, I want to thank everyone who enters this thread because my Subaru knowledge is limited. Someone I am close to has her 2009 Forester going in for the 3rd set of cam seals in less than a year. First time, around 10 months ago, near 147k, a cam seal failed and it was pushing an incredible amount of oil out. Car went in for a timing belt/tensioner/cam seals to a supposedly competent shop (though the owner expressed how much he dislikes Subarus). First failure was an original cam seal. About 6-7k later it starts dumping a gross amount of oil again. Shop fixed it and replaced the oil soaked timing belt too, no charge bad cam seal. Now about 4k later, oil pouring out again. Same side leaking as the two times before, above the oil filter. Are these seals difficult to install correctly? Any underlying problems that cause this? The engine doesn't seem to be making any excess blowby/pressure. By Subaru standards, the engine seems to be in pretty good shape.
 
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I'm a former mechanic at a Honda dealer and am now a semi mechanic. I'm guessing the shop is using junk parts and/or is installing them wrong. You need the right tools to drive the seals in. You don't use a socket. You also don't lube the seal on the outer edge to install it. The seal needs to be installed squarely, flush with the plane, not driven in past the plane. You put a little assembly lube on the cam snout and some on the inner part of the seal before installing. Bad parts and/or bad techniques ='s bad results. I would change the PCV valve as part of the job. Also, make sure she uses a proper oil filter with the same bypass setting specified by Subaru. Many of the aftermarket oil filters have a lower bypass setting.
 
I agree with skyactiv as well... no way the first set makes it 147k and then three sets in 10k miles it's an "out of spec cam". Poor installation methods cause good quality parts to fail every time. Take it to someone else and consider it lesson learned to avoid patronizing places that tell you they dislike your vehicle. It usually means they're not very competent in working on it, so it makes them angry little people inside.
 
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One thing I might want to consider, aside from poor installation, is that the camshaft itself has a grove worn into it...and like someone posted above, it requires a sleeve. That could be the case after 150,000 miles And I'll tell you what, I realize those seals had to be replaced because they were leaking, but I know people who won't replace cam seals because of preventive maintenance during a timing belt service. Because they don't want to open up a can of worms.
 
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Originally Posted by LazyDog
What about a bad PCV this can also caused some problems with internal pressure.
I agree with you on this one. Replace the PVC valve and check to see if there is a check valve inlne too. Also when replacing the next seals, I would acetone the head area that receives the seal. Then lightly scuff up the aluminum where the camseal sits in with 220 grit sand paper going around the radius of the hole to add micro biting edges. Redo acetone cleaning. Acetone the outer part of the seal and add Black Ultra Permatex around the seal (seal only) and do not start the car, push it outside and don't start it for 24 hours. .
 

Astro14

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Poor installation. On some cars, a plugged PCV system will absolutely force out the cam seals. They are the weakest link under internal pressure that shouldn't be there, so get that checked, too.
 
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these are great forums but model specific forums can be better for some issues. i have an audi TT + always was on VW vortex for my 01 1.8T jetta + although similar the TTforum in the UK is vastly superior!!
 
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Definitely throw a PCV at it. BMW makes a special sealant and very low profile syringe that youre supposed to use when replacing their seals now. Sometimes, some manufacturers want the car to sit for a few hours as well, probably for the seals to swell a bit and set up
 
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Originally Posted by LazyDog
What about a bad PCV this can also caused some problems with internal pressure.
Yeah I was thinking that too. I would stay away from RTV. Maybe apply some other tackifier - but only if factory shop manual recommended. If you Go to subaruforester.org and join I recall they have PDF of subaru shop manuals there. Bluesubie might know.
 
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Gasbuggy

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The way it leaks oil, it goes from nothing to a steady run out/smoke show/oil spots all the way at the back bumper. Like the seal falls out, if that's even possible. PCV is a good suggestion. Oil filter is a Fram Ultra which does not abide by the Subaru high bypass pressure. Does a lower bypass pressure put strain on engine seals?
 
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even genuine subie cam seals are super finicky. the basic rule of thumb is not to change them if they're not leaking. even subie pros, that can rebuild their engines blindfolded, using genuine seals, get leaks more often than other makes... i second posting this to a subie specific forum..
 
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Check crankcase pressure, check for any wear marks on the camshafts themselves and as stated previously check for proper installation with OEM parts.
 
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Originally Posted by wag123
At this point, I would be suspicious of and out-of-spec camshaft.
Yep.. that'll do it.
 
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Originally Posted by Gasbuggy
The way it leaks oil, it goes from nothing to a steady run out/smoke show/oil spots all the way at the back bumper. Like the seal falls out, if that's even possible. PCV is a good suggestion. Oil filter is a Fram Ultra which does not abide by the Subaru high bypass pressure. Does a lower bypass pressure put strain on engine seals?
The oil filter bypass pressure has nothing to do with the oil pressure itself (or the crankcase pressure), so this will not be the cause of your cam seal failing. What the bypass valve does in an oil filter is bypass the filter media under situations where the pressure differential across the filter media builds up. A couple of PSI difference in this spec between different oil filters is not critical. There is also a bypass valve in the oil pump which sends oil back into the pan when the oil pressure exceeds a specified PSI. If this valve is malfunctioning or plugged it can allow the engine oil pressure to get too high, THIS can cause a camshaft seal to fail. If the PCV system is not functioning properly and allowing excessive crankcase pressure it CAN cause a seal to fail, but the engine will also burn oil like crazy. I strongly suspect that the problem is either installer error or there is a groove worn into the camshaft. In this particular case I suspect that it is the latter since the other seal is not failing. As a general rule I do NOT recommend replacement of the camshaft seals unless they are leaking. When installing seals, an anaerobic sealant like Loctite 518 should be used.
 

Gasbuggy

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I'd like to think the shop would mention a groove worn into the camshaft after they ate the cost on parts and labor once already. I should know tomorrow what the outcome is this time.
 
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