Ok I don't want to disagree or argue about oil too much because I do recommend 15w40 rotella or other name brand but.... at normal operating temperature sae 30 is nearly identical to 15W40. Also they still make sae30 for diesels. http://www.westmarine.com/1/1/26377-delo-100-diesel-engine-oil-sae-30-5-ga.html
http://www.synthetic-motor-oil-change-and-filters.com/amsoil_products/amsoil_sae-30-product-code-acd.php

I like to use a straight weight in marine applications. SAE 30 designed for diesels will not harm the engine. it may not protect quite as well but is not the cause of low oil pressure.

OK, so its been a while since i've updated this posting but I finally got around to removing the oil pan with the plan to change the oil pump with a known good used one to see if this helps with the problem. When I removed the pan, I must say, I got a pretty good shock. I found several steel items in the bottom of the pan and one aluminum cast piece. The pictures are attached below. This is where I need some real expertise! I have no idea what this stuff could be. It appears that there is an outer race for a SKF sealed bearing of some sort. There appears to be the SKF printed on the outer aspect and the beginning of a part number, but the whole number is not there. The inner aspect of this race appears to be designed to contain ball bearings. I did not find the inner race or any bb. There is also what appears to be a steel dowel fragment as well, along with a rather large piece of aluminum casting.


I was further disgusted to find that there is a small hole in the oil strainer screen as well. I took apart the oil pump and found both gears to be galled significantly, so apparently some debris got into the pump as well.

So, other than the low oil pressure and associated lifter noise, the engine has no symptoms. It runs well, the injection timing is correct, and the cam/crank timing is correct. Both timing chains have no slack and there are no unusual noises when the engine is running (bar the lifters). With the pan off, I can see nothing out of place or obviously broken.

I wonder if there was some sort of previous mechanical failure, perhaps in the timing chain system that was repaired, but the pan may not have been removed and the debris never cleaned out. It seems with this sort of broken debris, there would be some other sign/symptom of trouble!

Also, for the 603 experts, where does the oil flow immediately after leaving the oil pump, does it go to the filter housing next (hopefully)?

I still have the pan off. I was planning to get some advice from you guys before just changing the pump and putting it back together with crossed fingers. Any help would be appreciated!

Attached Thumbnails

       

__________________
Patrick Frye

"Yeah, I'm crazy!!"

1986 300sdl
1982 300td

Gone but not forgotten:

76 240d
80 300td
81 240d - my first mercedes
81 300d
81 300sd
82 300td
82 300sd
83 300td
89 300sel

the last pic looks like a gear from something. I'd be looking for a diff engine if that mess has been through the engine...

__________________
hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

That gear is from the oil pump, I would get all that metal out and put new oil pump in and see what happens. All that metal does not look good but unless you want to open it up. I hope some of that metal did not get stuck in any oil passages or get stuck in the oil filter housing, open up the oil filter housing and make sure there is no metal in there. Also make sure that both chains are good, I would turn motor by hand and look at each chail link to make sure there is no damage. I think the smaller pieces of metal are from the vacuum pump, the bigger one is from the front of the motor under the crankshaft. I think the bigger one is under the crankshaft and is there to help the timing chain from falling off the gear when you change the chain. I think your vacuum pump failed and the pieces got caught in the timing chain and broke that big piece off.

Somebody slapped a new vac pump on that engine and left you to discover why, as fast as they could sell the car in running shape.

__________________
Cheers!
Scott McPhee

1987 300D

Yep, that is what I was thinking too.

I guess the good news is, the car is in running shape.

Could have easily tanked the engine by knocking the timing chain off, with the associated valve collisions.

I guess a saving grace is that from oil pickup goes straight to filter.

But debris could be lodged anywhere within that path if it got past the pickup screen.

__________________
Cheers!
Scott McPhee

1987 300D

x2

Sure, you can run it to failure if you don't mind sitting by the road waiting for a ride. Change the oil pump out and see if it makes any difference but if it were my car and I had a spare engine I'd be scheduling a weekend to swap it out. It would be interesting to dissect the engine that is currently in there.

This would cause me as much grief as any thing else you have aready mentioned:

__________________
Jim

The oil pump needs to be renewed, granted. Next item to check is the pressure relief valve, and filter housing. Clean out the pan and get on with life.

__________________

Gone to the dark side

- Jeff

Thanks everybody. Looks like it'll be going back together as is. I'll let you know what the oil pressure is like after the swap. Also, is there another relief valve other than what's a part of the pump that I should be taking apart and cleaning?

__________________
Patrick Frye

"Yeah, I'm crazy!!"

1986 300sdl
1982 300td

Gone but not forgotten:

76 240d
80 300td
81 240d - my first mercedes
81 300d
81 300sd
82 300td
82 300sd
83 300td
89 300sel