88 300E oil leak getting serious - PeachParts Mercedes-Benz Forum

cmcdonnell · #1 03-10-2007, 04:25 PM

I bought this car last month and noticed a few drops of oil on the driveway. Now it is a rather large rectangular puddle right under the front of the tranny. I bought some ramps today (Rhino plastic, pretty cool) and got under the car for the first time. It appears that the oil is coming from the oil filter housing area and dripping down behind the starter and blowing back. It was very hard to see anything. I can tell that it is not coming from the head gasket, it is dry up there.
Question: Is this a common leak and how do I go about repairing it, from under the car or from the top? Any help is appreciated.
Chris

softconsult · #2 03-10-2007, 04:53 PM

I don't get it. The oil filter is on the left side of the engine , if you are facing forward. The starter is on the right side. A leak from the timing chain cover is very common and blowing backward in the air stream is too. Don't think I've ever seen a post about a leaking oil filter housing.

Steve

psfred · #3 03-10-2007, 06:15 PM

Starter is on the left on the M103.

Replace your valve cover gasket and make sure the drain hole is good if there are any signs of oil leakage there.

I'd replace the oil filter, it's a spin-on and there is no reason to suspect that the gasket isn't bad. Worst case there are two there, but usually you dump out the entire crankcase full pretty fast as they won't stay in. I've never heard of the housing leaking, but I can easily imagine a spin-on filter leaking. In fact, the oil change place we use at work has had an entire truck load of bad filters appear -- replaced every single one due to leaking filter seams.

By a Wix filter, Hengst, Mann, or Bosch. If the Bosch is made in India, get one from a different maker.

Peter

cmcdonnell · #4 03-10-2007, 10:52 PM

Valve cover gasket and filler cap replaced last weekend. I wiped off the oil under the gasket to check for any leaks and so far, it is dry. What drain hole are you referring to, the one on the right side of the crankcase? I don't have a manual yet and am new to the M103. I was afraid to take off the filter today because I didn't have a spare, but will do it tomorrow. I guess I will be able to see alot more with it off. Thanks!

softconsult · #5 03-11-2007, 08:13 AM

I was definitely wrong, starter is on the left side as psfred said. I do recall that one time I did an oil and filter change on my M103 and experienced a massive leak. Really more like a dam breaking. I fired it up and drove off only to see the oil pressure guage descend to zero. I pulled over and shut it off.

Had it towed home. Turned out that the rubber seal on the filter had warped and didn't seal. Put on a new filter and all was well.

Steve

S-Class Guru · #6 03-11-2007, 07:11 PM

The oil pressure guage sender is right under the filter. I guess it could maybe spring a leak? Generally the valve cover gasket drips on the passenger side when it hardens and cracks cause it leans that way.

Good luck, hope it's a filter.

DG

cmcdonnell · #7 03-14-2007, 09:01 PM

I put a new Bosch (made in USA) oil filter on and it is still leaking. I got a look at the oil pressure sending unit and it was covered with oil. So that is the next step. My oil pressure guage is flickering a bit, but I thought that was pretty normal. We will see.

david s poole · #8 03-15-2007, 10:37 AM

the sending unit is going to be your problem.not uncommon especially with the age.

cmcdonnell · #9 03-17-2007, 11:44 AM

Sending unit replaced two days ago. Still leaking. Where can I get that dye used to check for leaks, anyone know?

david s poole · #10 03-17-2007, 12:01 PM

can you post some pics looking down from the top?

cmcdonnell · #11 03-17-2007, 01:16 PM

can you post some pics looking down from the top?
__________________

Sure, oil filter on or off? What am I focusing on?

cc260E · #12 03-17-2007, 02:00 PM

When you changed the oil filter did you keep the gasket on?
Did you lube it before tightening?

I suggest you try to check also the back side of the cam cover close to the firewall. the gasket has a strange shape see picture from the online catalogue

Good luck

cmcdonnell · #13 03-17-2007, 02:09 PM

The new filter comes with the gasket already attached. It is a modern type filter that just screws on like an american one. Only this one sits up top under the hood instead of below. Much different than my old 114's.

cc260E · #14 03-17-2007, 02:26 PM

Agreed the filters come with the gasket attached , it was just a suggestion, if not lubed it may be it wrecked.

This job in priciple is a very simple one, should not bring to oil leak.

check the cover gasket also

good luck

cmcdonnell · #15 03-18-2007, 12:19 AM

Here are the pics David requested, however it is difficult to see much.