Oil leak under intake manifold! Engine M104
 

Hi,
I have had all the typical oil leaks in my E280T 104 engine from 1994. The head gasket, the timing chain cover (top and lower part) and have managed to seal them. But I still have oil on my garage floor :-( The only place I can see oil now is in the area directly under the intake manifold, close to the head at the rear part of the engine (between the oil filter and the intake manifold). Does anyone know any particular source for this oil leak? Could it be the head cover seal?

Located the leak to the oil-to-heat exchanger
 

I think the oil-to-heat exchanger might be the source of the leak. Has anyone fixed a leak in this area before?

Could it perhaps be the two half-circle plugs at the valve cover-to-head seal? I forget what the procedure is, but I remember the manual had specific steps for reinstallation. You might want to use a mirror to inspect that area, though it's so tight that even that may not help.

I as well noticed oil in this area about 2 weeks ago. I was suspect to it being possiby from the power steering pump, somehow making its way up in this area. (since it was covered in oil) I have since cleaned the areas very well, from top, and from below. No oil around the PS pump, and no oil residue near the intake, as of yet. I am keeping my eye on it weekly, trying to find the source. I would really like to know where it came from.

FQ

Also--johan6504...how did you "seal" the leaks at the timing chain cover? Mine has some seapage, a few drops make its way down and rest on my swaybar about every oil change.

I think I resealed the timing chain cover five times before I got it exactly the way I wanted :eek:
The trick seems to be to get all the areas completly clean. I used an old tooth brush and some solvent (do not know the name in english) to clean all areas. I then proceded as describert in the repair manual. As I said it took me five times to get it perfect.


About the oil leak at the oil-to-heat exchanger I have added a picture of the unit.

Mine was leaking from the heat exchanger. I am pretty sure it was the gasket between the exchanger and the block. There was actually a missing mounting bolt that probably was the cause. I had my mechanic do it, took him about 4 hours, not a terribly difficult job.

I have also had the headgasket and front crank seal leaks repaired. It doesn't drip anymore! For now:(

I will have to get a beter look at it at home.

Should I remove the intake to get a closer look? It is tight back there.

There is probably a little more air space around the engine in my G-wagen but, I could see fairly well from the bottom. I would just get the gasket, how much could it be? THEN take off the intake with the intention of doing the fix all at once. Removing the intake just too look means that you run the risk of a leak if refitted without new gaskets. Why buy intake gaskets twice?

Roger that. Good point.