Help me cheat: Oil pan leak

I was minutes away from attempting the first start of the OM642 in der Scheißwagen when I noticed that oil was pooling under the lift.  After taking the oil pan insulation off and looking around, I discovered that the back right corner of the lower oil pan is leaking.  The oil pan doesn't use a gasket but instead calls for Loctite something-something-something to be applied along the mating surface.  Apparently, I must have missed or the bead of sealant got disturbed or whatever in that back corner.  I've run my endoscopic camera all along there and that's the only place that is leaking.  The correct answer would be to drain the oil that's left in there, remove the lower oil pan, clean the mating surfaces, re-apply sealant, and re-install the pan.  But....  removing the oil pan might be an engine-out procedure.  I may be able to sneak it in and out if I lift the engine within the confines of it still being wired up and bolted to the transmission, but I haven't investigated that yet.

Is there any way to cheat here?

The offending corner of the oil pan.  This is a few seconds after I wiped it clean and you can see the oil starting to seep through.

Actively dripping.  You can't see too well from this photo, but the upper oil pan directly about this is completely dry.  This is absolutely the source of the leak.

View of the right side of the lower oil pan.  The front of the engine is to the right of this picture.  The leaking area is just barely out of frame on the left side.  No oil is present along that ridge, confirming that the leak is definitely limited to the right rear corner.

I have only had moderate success with the external RTV job if I got the surface perfectly clean and oil-free....that leak is aggressive enough that it might be very difficult to do that.

Possibly a stupid comment...but are the bolts tight? I've definitely accidently missed one in the past when I was in a hurry.

Can you tighten the bolts around the leak a touch? 

Yeah, that was the first thing I tried.  They're definitely tight - I checked with the torque wrench and then gave the bolts back there as much torque as I was willing to do without breaking anything off.

Then I would loosen them, see if you can get a gun or tube of goo in there to fill any voids, and let it set up. Then tighten them again. 

You will need to drain the oil and wash the area down with a solvent to get rid of any oil. 

In reply to wae :

You know what they say - do it right or do it over.

I'd totally use whatever combination of RTV, Flex Seal, etc. kept me from having to drop the pan. 

I've never seen an RTV patch job actually work, and I have attempted my share.

RTV will just direct it to the end of the RTV patch and you'll have leaks from two places.  Flex seal probably would work until you got a tiny bit of positive crankcase pressure and then it might fail.  Worth a shot and I hate being a Debbie Downer, but don't get your hopes up.

I vote for doing it right.  Remind me what it's installed in?  Only Bluetec I remember working on was in an E350 and I didn't have to pull the engine to get the pan off.  I'm trying to remember if I had to pull a mount and lift the engine a bit.  Too many years ago to remember.

I'm also trying to remember if this was one of the ones that the aftermarket ended up making an actual gasket.  Some of the MB OM6xx engines was so notorious for pan leaks that Victor Reinz and a couple others made gaskets to solve it.

Is it possible that the bolt is bottoming out and not squeezing the gasket completely?
 

maybe an extra washer or 2 would help , 

good luck

Ive had moderate success drawing a vacuum on the crankcase with a shopvac to draw sealant into the offending area.  

Again...moderate...

I figured that there wasn't a high probability of fixing it without dropping the pan.  This is in the GL350, so there's a lot of front diff and subframe sitting right under the engine.  It appears, though, that I can pull the motor mounts and lift the engine enough to sneak the pan out according to the factory procedure.  Unless I want to try doing that on my back, though, I'm going to need to rig up something to approximate the "special tool" that sits across the engine bay and holds the motor up.

In reply to wae :

A pair of sistered 2x6 and a ratchet strap has worked well for me on other cars

In reply to Dusterbd13-michael :

Not a bad plan.  I'm looking at an old 4x4 and a bucket of ratchet straps that are laying around here at the shop and getting ideas.  What I am not going to do is try to put something under the car on the lift and lower the whole car down while holding the engine up.  I've got a  pretty high risk tolerance, but that one crosses a line even for me!

Use a good ratchet strap.  I like to use the trucker-style 3" that says 3333 lbs.  Overkill, but I don't trust the 1" motorcycle tie-down straps.

Not sure what your chassis looks like, but I've also done it before where I jacked up the engine with a floor jack and slung a strap under the crank pulley and hooked it on the UCA mounts or a hole in the frame rail.  Like a hammock.  That eliminates the possibility of the 2x6 breaking and also skips the need for the purchase of a single-purpose shop tool like an engine support.

I've definitely done a 4x4 across the strut towers and a ratchet strap to approximate the engine support tool on fwd cars before

I have an almost religious devotion to Toyota black sealant. I'd loosen the pan bolts and try to clean the area and squeeze some of that stuff in there and then tighten everything back up, to try to save the engine out procedure. But I wouldn't try using anything else. My rallykar started leaking around the front main about halfway through an event several years ago. We goobered some toyota black on there and finished the rally. It um hasn't leaked since. I rekkin I'll replace the relevant seals after my shop is built and the lift is installed...

I've used one of these.

https://www.harborfreight.com/1000-lb-capacity-engine-support-bar-96524.html

Oil leaks are the f'n devil, and that's a lot of oil before a first startup.  Were all the pan bolts the same length?  Californiamilleghia may be onto something with the washers, if a few are bottoming out.  

I like Hondabond on perfectly clean surfaces, allowing it to skin over a little, and following the torque sequence and pattern exactly.  Then you let it cure for 24 hours and say a little prayer. 

If there were a good (or bad) cheat for this, every used car lot would already know about it.  If it were just a little seepage, I'd stuff a boat bilge tampon under, between the undertray...rinse and replace every oil change.  

$90 for the chinesium version of the engine lift doesn't seem like a terrible deal, actually.  The other times I've needed this, I either didn't have or couldn't use the lift, so the regular engine crane worked just fine.  When I have a couple minutes to rub together, I'm going to try the 4x4s and if that starts to look too sketchy too fast, I'll buzz out and get the tool.

As much of a PITA popping the pan is going to be, that's going to be a better choice for me as opposed to trying to sneak more sealant in.  I kind of figured that there are enough cars that the oil pan is an engine-out procedure - or at least a really big job - that if there was a quasi-reliable cheat I would have heard about it.  I'd try the Hail Mary if the whole thing had to come out, but for this I might as well do the thing.

Maybe loctite green?  It's wicking and might fill in the gap.

Clean it and apply Right Stuff.

i have actually got the "caulk the outside with Right Stuff" to work on the bottom front corner of an E46 330xi oil pan.  Where they all leak.

Key was clean, clean, clean some more, like you could TIG weld it clean, and applied far greater a distance than it appeared would be needed.  Pushed it into the crevice, was not stingy.

If it wasn't an understanding friend-of-the-owner, and wasn't being done for free, and wasn't an all wheel drive E46, i wouldn't have bothered trying because it never works.