rear engine seal leak (Blue Devil Sealer?)

[brus brother]

Car not really worth much at this point 05 OB 200K miles. P0420, needing HGs and TB. Wonky climate control. Body is in great shape and I barely drive it as our second car.

Anyway, the driver side VC gasket is leaking and will be addressed but there is a good size drip from the rear engine seal that I am hoping I can use a bottle fix.

Anyone have any experience with Blue Devil Rear Main Sealer? Am I just looking for more trouble?

Just getting embarrassing leaving an oily mess when I park the car in friend's driveways.

Edited June 19, 2020 by brus brother

[idosubaru]

1 hour ago, brus brother said:

Car not really worth much at this point 05 OB 200K miles. P0420, needing HGs and TB. Wonky climate control. Body is in great shape and I barely drive it as our second car.

Anyway, the driver side VC gasket is leaking and will be addressed but there is a good size drip from the rear engine seal that I am hoping I can use a bottle fix.

Anyone have any experience with Blue Devil Rear Main Sealer? Am I just looking for more trouble?

Just getting embarrassing leaving an oily mess when I park the car in friend's driveways.

Are you absolutely positive it's a rear main leak?  100% of the "i have a rear main leak" Subaru's I've encountered don't end up being rear mains. Subaru rear main seals rarely leak.  Of course it can, and does, happen, but valve covers, oil pans, and HG's drip and blow enough oil centrally and back in that same cross member area that people are prone to misdiagnose it. 

If you're sure it is: 

Go for it.  I doubt it'll cause any issues, it just isn't likely to solve any.  Follow the guidelines to get your money back and it's a free trial when it doesn't work. 

If it's ever been run hot, previously replaced, aftermarket seal, it's even less likely to work, though the original seal isn't likely to respond either. 

 

[brus brother]

Alright then I'll verify before using magic goop in a bottle.

I know the HGs are leaking (it is a Subaru after all) specifically on the passenger top side where that channel runs across, (not the sensors as I had hoped) and for sure the driver VC gasket  so hey wouldn't be surprised if the oil pan gasket might be a contributor to the party.

Just need to clean up my act or start renting the car out to seal driveways.

[heartless]

do they still have the rear oil separator plate like on the older 2.2s?

If they do, my bet is the leak is from there, and no amount of "fix in bottle" will fix that. The only way to fix that is pull the engine and reseal properly - and if you are going to do that, may as well do all the other stuff it needs. If the body is still in good shape, it might be worthwhile to do it. 200K really is not that high on the mileage. My 02 Forester has 260K and going strong

As already mentioned, it is fairly rare for the main crank seal to leak.. yeah, it does happen, but not that often.

[carfreak85]

I would seriously recommend against using a stop-leak fluid for your oil leak.  Those additives tend to make a mess inside your engine and for the most part, they don't even work.  As mentioned above, I would take a look and try to find the source of the leak and fix that.  My guess is the oil separator plate on the back of the engine, valve cover gasket or possibly the head gasket itself.

[x-t-c]

F.Y.I. from a guy who used to work selling auto parts and magick in a bottle chemicals.  99% of stop leak types of magick in a bottle is barely more than pure brake fluid! The thought is that it will swell the seals and make them stop leaking that way. Of course everyone who knows anything about brake fluid also knows that it also starts to eat at "rubber" type components.  So it may work for awhile, but in the end it will totally destroy ALL  the seals.  So i wouldn't use it in a vehicle i was keeping for any length of time. 

[brus brother]

Interesting to note that the trany fix in a bottle for delayed engagement seems to work out nicely.

Posted here for many years.

Also SOA offers their fix in a bottle  for external HG leaks.

Not saying your statement is incorrect but there do seem some snake oils that actually have some merit.

 

[Rampage]

Try a quart of Lucas Motor treatment. It may not stop the leak, but should slow it down. I use it in our EJ22s.

There are several snake oils that work, like the little red tube that stops cavitation in older GM torque converters.

And the Trans-X that I learned about here for our power steering leak. I was adding fluid every other day, now it is just a little once a week. It did not cure it, but it helped. Our RHDs are going to retire the end of August, so I hope it holds up till then. If not, I have the kit to rebuild the rack.

[idosubaru]

On 6/19/2020 at 3:26 PM, brus brother said:

Alright then I'll verify before using magic goop in a bottle.

I know the HGs are leaking (it is a Subaru after all) specifically on the passenger top side where that channel runs across, (not the sensors as I had hoped) and for sure the driver VC gasket  so hey wouldn't be surprised if the oil pan gasket might be a contributor to the party.

Just need to clean up my act or start renting the car out to seal driveways.

Replace that leaking VC and most of the leaking could easily disappear.  That's easy and cheap.

With that description, 99.5 times out of 100 this is a misdiagnosis. Most of this might be the valve cover - those gaskets get hard as a rock and leak like sieves.

Clearly this vehicle is worth as much to you as a termite infestation in your home, there's hardly a reason to think about this much - go give it a try. 

You would be looking at additives through anecdotal rose covered glasses. Fluids/additives work rarely, and usually on parts that were problematic from the factory, rather than old, brittle/delapidated/warn seals that are beyond hope.  Those valve cover gaskets will be so hard and brittle that nothing will fill those gaps unless it also solidifies the entire crankcase.  I've pulled hundreds of valve cover gaskets, old ones are always brittle, hard, and have zero ability to seal. 

[carfreak85]

15 hours ago, brus brother said:

Also SOA offers their fix in a bottle  for external HG leaks.

Not saying your statement is incorrect but there do seem some snake oils that actually have some merit.

 

A branded version of Barr's Stop Leak was authorized by SoA to help limp EJ25 engines to the end of their powertrain warranty periods before the HGs finally let go and would have to be repaired on Subaru's dime.  Had there not been HG issues with the EJ25 in the first place, be absolutely certain that SoA would NEVER recommend servicing the engine oil, or coolant systems, with anything other than the recommended fluids.

I base the above knowledge on my experience as a senior design engineer at a vehicle manufacturer.

[moosens]

Just move on and be thankful she gave you all she did. 
 

Sounds like a nice $500 beater for the next guy , which is really nonexistent these days so let’s say it’s a $1500 beater. 
 

Hope that doesn’t hurt your feelings. I don’t need it but my friend has a 2005 if it comes to ever dumping it off. I know you won’t be parting it out. 
 

You retired guys need reliable cars to get to your golf games and lunches with your friends.

[Rampage]

Last week I did the valve cover gaskets on our 95. I used pliers to wiggle them out and they were so hard they kept breaking.

[brus brother]

On 6/23/2020 at 5:31 PM, moosens said:

You retired guys need reliable cars to get to your golf games and lunches with your friends.

... not me. Geezers stay home in Covid days.

Past three weeks, replaced the pool filter and changed 300 lbs of sand, re-grouted the pool wall tile (day spent leaning over the edge), reset stones in front pathway, pressure washed pool deck and all walkways, cut down six large trees overhanging the pool, trenched some new drainage pipe, re-stacked stone wall...

I have friends and do eat lunch, but what is this golf game you speak of?

I'll change the VC gaskets and save the environment and drive that sucker till the wheels fall off.

[ThosL]

I've had good luck with the Lucas products.  

 

With Blue Devil be sure to keep the receipt and read the guarantee terms, they don't like to pay out.  If they balk if it doesn't work and don't want to reimburse you, go to the state consumers agency and that should do the trick.