Oil under the dash and other Shlomo malaise - PeachParts Mercedes-Benz Forum

iNeon · #1 02-01-2007, 11:04 PM

I'm slowly working through Shlomo's issues, but ran into another while fixing one...isn't it always the case?

There's oil all under the dash-- I discovered it whilever I was fixing the amplifier and seat heating systems(a new addition from a w126 500SEL, factory stuff!! mmm) and had the console out. What's the best way to clean all of that? Do I leave it and relish the even more pungent 'old Benz smell?"

Secondly-- What is the most likely cause? Is it the shut-off valve I'm assuming, or would my vacuum pump be doing it as a way of saying it wants attention? Could this be related to the hard brakes?

On brakes-- Flushing the fluid is on the agenda for tomorrow afternoon, and that seems straight-forward, but could really old fluid make the pedal hard? I know just enough to be dangerous thinking I know more than I do...

Steering-- I found a quarter-sized chunk missing from one of my front tires, and assume that's where the shimmy is coming from, I'll order a steering shock, get new tires and set the steering box play before getting an alignment and then see where that is.

How hard is the rear differential mount to change? I've had one sitting in the trunk and may try to put it on tomorrow-- I think that may raise the rear of the car the little bit the shocks didn't.

Thanks again, ya'll! Maybe this summer I'll bring the potato salad to a south-east get together! Howcome the Texans are having all the fun?!?

Biodiesel300TD · #2 02-01-2007, 11:24 PM

Oil--Are we talking drips and puddles or just oily wetness? There are two places the oil could be comming from. The most likely is from the oil pressure line that connects to the instrument cluster. The other less likely is the ignition vac lines. I doubt the ignition like could leak enough to make drips. Either pull your instrument cluster out or remove the under dash panels, then see where the oil is comming from. If its from the oil pressure line, pull the instrument cluster and try tightening the connection. If it's from the ignition you need a new shut-off valve.

Differential Mount--Pretty easy to replace. Support the differential with a jack, pull the 4 bolts out of where the mount is bolted to the frame. Lower the differential enough to get at the 2 bolts holding the mount on the differential and it's out.

Jeremy5848 · #3 02-01-2007, 11:44 PM

Mercedes says the four bolts that hold the diff mount to the car's floor must be replaced but you can just clean the old ones and put on new (blue) Loc-tite. It's not a difficult job. If you can clean underneath first it will be a nicer job.

Eskimo · #4 02-01-2007, 11:54 PM

Quote:

Originally Posted by Biodiesel300TD

The most likely is from the oil pressure line that connects to the instrument cluster.
...
If its from the oil pressure line, pull the instrument cluster and try tightening the connection.

If the oil seems to be coming from this general area, another possible culprit is the oil gauge itself. Sometimes the Bourdon tube develops a leak.

iNeon · #5 02-02-2007, 12:00 AM

Well, most of my pants have a single black circular oil stain on my accelerator leg

so I assume it's coming from the right side, but it could also be dribbling down some wire or something and dripping there.

I'll make notes tomorrow during the day and let you know-- I do know the back of the cluster seemed to be fine when I pulled it out to wire in the grounds to the seat warmers. This problem predates that by about a year

I'll also make a mental note to not park the car on a hill whenever I do the rear differential mount

DeliveryValve · #6 02-02-2007, 12:12 AM

I would bet the oil is dripping from the vent hose that leads from the VCV to under the dash. You should find the end of the line somewhere around the steering wheel mount. Most likely culprits of leaking oil are the shut off valve or the vacuum pump. You should hook a mity vac to the shut off valve and see if it holds pressure or sucks in oil. Also you should unhook the booster line (the vacuum line going to the pump to the power brake booster) examine it for oil, and then see what type of vacuum you are getting with the engine running. You should be getting around 23-25” hg. Low pressure to the booster can make your brake peddle feel hard.

Good Luck.

BTW – I recommend clean up the oil mess how ever you can.

yellit · #7 02-02-2007, 12:18 AM

On my 240D it was the gauge tube itself but sounds like yours may be associated with the line from the cut off valve or ign. switch hose attachments(If there is unwanted oil in the vac lines)...... Being that it seems to occur on the right side....
Real easy to see all of this if you pull the cluster again.....
The old pungent smell idea is ok too....kind of an all encompassing, warm, comforting, familiar, relaxing, Benz funk....they should make an air freshener with that scent....

compress ignite · #8 02-02-2007, 01:56 AM

IF the shut off valve on the Injection pump is bad... It is possible for the engine
oil that lubricates the Injection pump to be "Pulled" up into the passenger area
as far as the climate control system. (after it pollutes the ignition switch area.)

('84 300SD... lots of careful flushing with brake parts cleaner.)

Mustang_man298 · #9 02-03-2007, 01:32 AM

Quote:

Originally Posted by Biodiesel300TD

I doubt the ignition like could leak enough to make drips.

I've got a nice long black streak down my driver side tunnel carpet that begs to differ with you on that one....leak was caused by the oil in the vac lines making the ignition lines turn into sponge and drool, pulled right off just by touching them. Happened under previous ownership, but I found and repaired it. I used some formed neoprene vacuum elbows from the sensors on the manifold of an 80's chevy truck, worked great.

yellit · #10 02-03-2007, 07:23 AM

Yep I think those were real soft on my 240D if I remember correct....The hard plastic lines were ok for now ....It was the two little rubber pieces that I replaced with one of those new (Y) vacuum connectors that I cut into 3 sections....
I ended up changing every rubber connector in the car on the vacuum system....that helped stop those slow vac leaks...The hard lines are next...After 27 years they have become brittle.....they do not leak but if you move them very much.... they break

t walgamuth · #11 02-03-2007, 07:41 AM

hard brake pedal could be one chamber failure if the hardness appears about half way to the floor.

or if it is just hard everywhere i can be a booster problem or just lack of vac to the booster. do your door locks work? does it shut off well?

tom w

cavaliers16 · #12 02-03-2007, 01:04 PM

Quote:

Originally Posted by iNeon

Well, most of my pants have a single black circular oil stain on my accelerator leg

so I assume it's coming from the right side, but it could also be dribbling down some wire or something and dripping there.

I'll make notes tomorrow during the day and let you know-- I do know the back of the cluster seemed to be fine when I pulled it out to wire in the grounds to the seat warmers. This problem predates that by about a year

I'll also make a mental note to not park the car on a hill whenever I do the rear differential mount

I feel for you- my oil pressure line developed a leak that caused oil to puddle at the lip on the kick panel. One hard stop at a light caused a wave of jet black oil to spill all over my pants, socks, shoes, and even worse, my 300D floormats! It was very easy to fix the line, but impossible to get the stains out of the carpet.