Upper oil pan weeping oil

[jabstick420]

Got under the car last night to remove the steering box and got a good look at the upper oil pan.


Lots of oil seeping, and visible sealant that I could scrape off with my finger.


I had a "friend" who removed the pan and applied sealant in hopes of stopping a previous leak.


Later found globs of sealant in the lower oil pain.


So, assuming this was done improperly, is there anything I can do short of removing the engine? ie, tighten the pan bolts? use different oil, etc


currently using delo400se

[greazzer]

I don't think it's possible without pulling the engine ... plus, if you pull the upper pan, you might as well replace the front and rear crank seals ...

[Diesel911]

You might try loosening the pan bolts a bit and getting the torque specs and pattern and torque the pan bolts properly and see if that helps.

Also check to see that the crankcase pressure is venting out (no restrictions in your vent system).

[jabstick420]

I am not qualified, nor equipped to pull an engine,


so I will probably try retightening to spec.


seems that there are a lot of tight spots though.

[Dan Stokes]

Having had my upper pan off I can tell you the process:

Of course, you have to pull the pan. Though I'm not sure in the Mercedes chassis I think the guys are right that the engine has to come out though maybe you can take the mounts loose and pick the engine up w/o actually removing it (that's only a thought on my part).

Then the lower pan and upper pan have to come off and the upper pan, especially, has to be operating-room clean.

Here's the reason for the super cleaning job - the upper pan does NOT use a gasket or anything of the sort. Instead, you use an anerobic sealant (I used a LocTite product - there are others). This is applied VERY sparingly such that the seal is basically metal-to-metal from the upper pan to the block. The sealant just fills minor imperfections so if there is ANY crud on the pan rail it can't seal.

The lower pan seals with a standard gasket (available from Pelican) and you'll want to make sure that the pan rail is fairly flat just like you would for a steel valve cover gasket. You could use a tiny swipe of RTV or similar sealant on the lower pan but that should never be used in this situation as a bead - it WILL ooze out and go places you don't want it.

I think it's well worth retorqueing the upper pan and see if that helps. Cost = nothing and it might help. Some of the bolts will be a challenge to reach but with swivel sockets and long extensions you might be able to get 'er done.

GOOD LUCK!

Dan

[jabstick420]

Originally Posted by Dan Stokes

The lower pan seals with a standard gasket (available from Pelican) and you'll want to make sure that the pan rail is fairly flat just like you would for a steel valve cover gasket. You could use a tiny swipe of RTV or similar sealant on the lower pan but that should never be used in this situation as a bead - it WILL ooze out and go places you don't want it.


Dan

So its a bad sign that there were globs of sealant in the lower pan?


perhaps too much sealant, and maybe the wrong kind were used.


the guy is a good mechanic, maybe a little on the lazy side, and perhaps didn't want to be super diligent on an old vehicle

[oldsinner111]

I read before never use that stuff.It is bad for oosing out and clogging oil pickup screens.I use permatex form a gasket if needed.Rocker arm gaskets are bad for moving around.So I use it as a glue to hold the gaskets.However leaks,that are not to big,I have cleaned area good with brake cleaner.Taking chewing gum to crack,then super glue gel,and paper. For perminate fix.

[Dan Stokes]

Originally Posted by jabstick420

So its a bad sign that there were globs of sealant in the lower pan?


perhaps too much sealant, and maybe the wrong kind were used.


the guy is a good mechanic, maybe a little on the lazy side, and perhaps didn't want to be super diligent on an old vehicle

It's not good! I put a tiny thread of RTV (usually red - it's high temp) and then put on a rubber glove (I KNOW you have those!) and smear it all the way around the gasket by holding the gasket/sealer between your thumb and forefinger. Anything that wipes onto the glove is thrown away with the glove. The gasket gets coated evenly and thoroughly but with a very thin film of the sealant.

Oldsinner has a point. A lot of folks say never to use it because so many people use too much of it so that it does ooze out and get all sorts of places it shouldn't be. But it can be used well - sparingly - and it will seal like crazy as long as the mating surfaces are clean to start with. The upper pan and its mating surface on the block have to be crazy clean while the lower pan and its mating surface on the upper pan just have to be regular ol' clean.

The Mercedes lower pan is VERY heavy gage steel and mine had a really flat mating surface but you do need to check it and gently tap it flat with a hammer if it isn't (it'll probably be fine). Just be aware that a bent pan rail can impeded sealing.

Good Luck!

Dan