This is my first post here so wanted to say thanks in advance for the help.

So my father in law has a 1990 300CE that I have been entrusted to care and maintain for him. It seems to have developed a leak that equates to 1 - 1 1/2 quarts every 2 to 3 weeks. So in getting under the car today to replace the voltage regulator I started looking at the bottom of the motor and it seems like I have 2 separate issues here.

1. The first oil leak seems to be the front (passenger side) pan gasket - Is there anything else in this area that may be leaking that I am missing (oil pressure sender, oil pump, etc...)

2. The second leak seems to be at the Oil level Sender - The electrical connector that slips onto it has deteriorated and there is no plastic around it anymore and it appears to be weeping. So I have not found where I can get a new sender wire.... is this going to be a dealer only item?



Also should note I have done the valve cover gasket recently as well.

Thanks in advance!

So I found this one........ http://www.peachparts.com/shopforum/tech-help/309687-repairing-oil-leak-1991-mb-300ce.html


Timing cover seal.....seems likley

I believe you have the m104 engine, they commonly leak through the front timing cover, the pan gasket and the rear main seal. But with oil leak could come from anywhere. I reckon you should give the engine a really good wash from underneath drive it for a couple of weeks and recheck it. That's my suggestion

I'm not exactly sure where you could get a new sender wire from and I believe it is a part of the wiring harness!!

Steve, as mentioned the joint between the upper and lower timing chain covers is a common leakage area. Do a "Search" by timing chain cover ... there is considerable information about that repair.

Double check that the valve cover gasket is seated properly at the back of the engine. It typically happens that the gasket gets misaligned in the back resulting in a large leak. Use an inspection mirror and a flashlight to closely examine that area to verify the half-moon portions of the gasket are seated properly on the head and in the valve cover.

Replace the O-ring on the oil level sender. Best to do that job during an oil change with the oil pan drained.

__________________
Fred Hoelzle

Steve, you also may want to check the rear of the head gasket as well. Another area of leakage due to higher mileage.

__________________
Norm K.
'97 E420 Sport
'06 E350 Sedan
'67 Mustang Coupe
'70 F-250
'15 VW Jetta

Thanks guys for the quick responses.... so to date here is what i have checked.

Transmission was rebuilt 30K ago and they did the rear seal when it was out so that's new- not to say they might not have nicked it when they put it in.

Used a mirror to circle the valve cover and head - No oil traces at all anywhere on the valve cover or head.

Read the DIY Timing cover post and went and checked the cover by the Dizzy and it is pretty wet there so I think I found the leak (or one of them).


So I would never have thought that a small seal like that could leak so much oil!

Ordering the gasket, Camshaft seal and oil sender o-ring today and just going to knock them all out since the car has 170K and has had no major rebuild services on the motor.


Thanks again for the quick replies and the wealth of knowledge on the site......helps allot as I am a SAAB guy.