Subaru Oil leak and Pressure issue: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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April 13, 2011 8:34 p.m. tb Reader

I could use some experienced opinions on this one, please. The car in question is a 1998 Subaru Legacy Outback wagon auto (ej25/4eat?)

Last week after a long trip I exit the vehicle and smell burning. At least half a quart of oil is on top of the passenger side of the engine . I noticed oil slowly bubbling and weeping from the pressure sending unit and nothing else of great significance.

A couple days, $10 and an hour's work later the new sending unit is in with no leaks and all is well with the world.

A couple more days of typical errands with no issues pass and I feel rather pleased with myself, for a change.

Today I attempt a trip to the grocery store and I foolishly decide that I will take the suv out in the bad weather. A couple miles down the road and the oil pressure light flickers on and I shut if off quickly on the side of the road and climb out into the wind and rain to inspect things. I find more oil on top of the passenger side of the engine, mainly behind the steering pump and under the intake runners, but not much really. I add 1/3 quart and gently drive home after verifying several hundred times that the oil level is perfect.

So:

Oil leak on top of engine under intake runners

New oil pressure sender (in this area)

No leaking from new sender / plug

still leaking a bit; not sure from where!

oil pressure light blazing in defiant mockery on dash plenty of oil in engine

Thinking:

bad sending unit / berkeleyed up installer (me)

170k mile orig oil pump starting to die

broken something I haven't noticed yet but is common and simple and someone here will tell me exactly how to fix it

Thanks for listening, any input appreciated
April 13, 2011 8:52 p.m. SlickDizzy SuperDork

I can tell you one thing, it's not the oil pump unless it's gushing out down the front of the oil pan. Valve cover gaskets maybe? Bad EGR hookup? I'll brainstorm on that for a minute...
April 13, 2011 9:00 p.m. tb Reader

SlickDizzy wrote:

I can tell you one thing, it's not the oil pump unless it's gushing out down the front of the oil pan. Valve cover gaskets maybe? Bad EGR hookup? I'll brainstorm on that for a minute...

The front and bottom of the block are certainly dirty and covered in E36 M3 but it does not appear that there are any fresh leaks there.

The valve cover gaskets look bad and dirty, but more in an old and grimy sense versus a fresh ooze look, if that makes sense?

I like the EGR thought and will check it first. I did look at that area recently but it is such a strong suspect that it needs to be reexamined.

Thanks, I know a lot less about these quadrizontal things then I should and I appreciate the help
April 13, 2011 9:31 p.m. Hocrest Reader

Get rid of the aftermarket OP sender. These and coolant temp sensors are items that I don't even bother getting from anywhere but Subaru. I know enough people including myself that have had to replace these shortly after using aftermarket.

Are you sure it's engine oil? If the ATF in the steering reservoir is old and mixes with dirt on the block, I've seen that look fairly dark. There is an O ring between the tank and the pump that should be fairly dry and brittle by now. I replaced the one on my 97 Leg last week.

edit- Mods, I accidentally hit the "note" button on the above post. Never mind, nothing to see here.
April 13, 2011 10:03 p.m. tb Reader

Hocrest wrote:

Get rid of the aftermarket OP sender. These and coolant temp sensors are items that I don't even bother getting from anywhere but Subaru. I know enough people including myself that have had to replace these shortly after using aftermarket.

That sounds easy enough; I thought I was getting lucky finding them so cheap from a decent name brand but sometime oem does work best

Are you sure it's engine oil? If the ATF in the steering reservoir is old and mixes with dirt on the block, I've seen that look fairly dark. There is an O ring between the tank and the pump that should be fairly dry and brittle by now. I replaced the one on my 97 Leg last week.

I am pretty sure that it is oil at this point. I have been through the thinking it was atf from the steering pump but the reservoir seems to be holding steady after a recent topping off. I will be sure to keep a good eye on this area also because I will not discount the possibility , but there is plenty of oil further back on the block. Sounds like this o ring is a good idea, you know, while I am already in there...
April 14, 2011 3:00 a.m. ValuePack Dork

Leak at the head gasket? I've only seen external HG oil leaks on SOHC cars(which this is not) on the underside, but stranger things have happened. Cracked head?

Best of luck!
April 14, 2011 6:17 a.m. 44Dwarf Dork

Wash the motor down nice and clean. Dry it with the leaf blower and or wait a few days. Spray with anti-fungal foot powder. Wait for it to dry to bright white. Start motor and run it a few minutes. Inspect. the oil will turn the white to a streak of brown or red.
April 14, 2011 11:57 a.m. tb Reader

ValuePack wrote:

Leak at the head gasket? I've only seen external HG oil leaks on SOHC cars(which this is not) on the underside, but stranger things have happened. Cracked head?

Best of luck!

I have read about the HG issues with the SOHC (somehow "overhead" feels wrong in this case) and this does not look like this. Besides, like you said, different beast.

With where the oil pooled, I would be more concerned with a cracked block near the crank, but I am sure I would have noticed that by now...

Thanks
April 14, 2011 12:02 p.m. tb Reader

44Dwarf wrote:

Wash the motor down nice and clean. Dry it with the leaf blower and or wait a few days. Spray with anti-fungal foot powder. Wait for it to dry to bright white. Start motor and run it a few minutes. Inspect. the oil will turn the white to a streak of brown or red.

I think that this is where I am at right now. I poked around this morning but did not find much of interest.

There was plenty of oil on the bottom near the rear of the engine, which is new to me. I could see where some was dripping onto the cross-member and also exhaust Y but nothing conclusive until I clean much better.

I'll pick up some more engine cleaner and foot powder later. I was thinking the same thing except with baking soda but an aerosol spray can sounds like a better idea.

Thanks for all the tips
April 14, 2011 4:54 p.m. BobOfTheFuture HalfDork

Best I can say, is Subarus seem to really dislike any sensors/etc that arent from Subaru/fuji heavy.

I would bet that the new oil you are finding is leftover from the old sensor leak, and the new sensor isnt doing its job correctly.
April 16, 2011 10:53 a.m. tb Reader

BobOfTheFuture wrote:

Best I can say, is Subarus seem to really dislike any sensors/etc that arent from Subaru/fuji heavy.

I would bet that the new oil you are finding is leftover from the old sensor leak, and the new sensor isnt doing its job correctly.

I hope that this is the case, and it sounds fairly likely. I swapped in a fuji heavy sensor and it seems to be much happier. No indicator light on dash and no visible leaks on the top.

I am not done cleaning up the engine compartment, but I do suspect that most of the oil was leftover dripping. There appears to be a small leak from the rear lower corner of the passenger valve cover gasket that I will keep my eye on, but it does not appear to be enough to take anything apart yet.

Thanks again to everyone for the help, hopefully this will settle the issue