have any ideas as to where I should start..... I made the mistake of commenting here a month or so ago that I clock around 50K a year and had never been stranded; nix that boast.

Started out on an airport run yesterday (130 miles each way) with the 300SD. The night before I had installed a new shutoff valve and changed the engine oil and filter. On the highway about 65 miles from home (at 70 mph) I noticed that temp had crept up to about 100c (never have seen the temp that high in the sd even at 90 degrees with ac on) ambient temp was at about 75f. Another mile or so and I thought I heard a regular"tick" (as in valve train) from up front. Slowed down to 55 mph and oil pressure dropped to 2.5. As luck would have it I was right at an exit and pulled off the highway. At the end of ramp stop sign, oil pressure dropped to .5 with valve train clattering to beat hell; pulled over to the shoulder and shut it down. Glad that I have the upgraded AAA plan with 100 mile towing plan - got on the horn, rented a car, and had the MB trucked back to the ranch.

Oil level is right on the mark, no leaks anywhere. Started cold this morning and pressure jumped to 3 immediately, although there is a slight valve tick.
Didn't let it run long enough to warm up.

Odo indicates 151K, but is not entirely accurate (adds about 60 miles for each 100 that I drive) I have put about 15K on since I brought it home in May. In that time oil pressure has been consistant with that of my 190D; 1+ at idle (warm) popping to 3 by 1100 +/- rpm's.

There was no lower engine noise (as in rod bearing knock) only valve train clatter which I can only assume was from lack of oil. My guess is either oil pump failure or perhaps a main bearing. Any ideas anyone??

Jim

__________________
2005 C240 4matic wagon (daily driver)
87 190D - 225K (on loan)
85 190D - 312K (on loan)
2011 Subaru Legacy AWD (Wife's)

I would suspect the oil filter, or its installation, restricting oil flow and lowering pressure. A plugged (defective?) oil filter, or leaking o-rings, may let oil pressure drop.

The filter is a likely suspect since you had just replaced it. I don't think it's the pump, since you got good pressure. It's probably not a main bearing, either, they are quite durable and don't just go bad.

If you have been doing your own O&F, you are familiar with the procedure. Double-check everything. Replace oil filter again if in doubt.



Let us know...

Best Regards,
Jim

Change the oil filter for sure. Use a different brand than what's in there now. When you have the filter out, check that the 3 rubber grommets (top, bottom, middle) are all in place. Check the filter cannister to make sure that a loose grommet from some previous filter is not stuck in the bottom.

__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

Replaced the Mann filter with a new one (all that I have in stock - auto parts is a 40 minute drive each way). Also replaced both o-rings on the filter cover stem. Pressure ok at start-up but down to 2.5 by the time it warmed up to 50c. Sharp rapping noise at front end (up top - assuming valve train), worsening as pressure drops; also idling rough, appears to be missing on one of the front two cylinders. Think I will have a bite of lunch then pull valve cover.

Any more ideas greatly appreciated!

Thanks again,
Jim

__________________
2005 C240 4matic wagon (daily driver)
87 190D - 225K (on loan)
85 190D - 312K (on loan)
2011 Subaru Legacy AWD (Wife's)

kind of oil are you running?

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

John Deere Plus-50 Supreme. Supposedly one of the best dino diesel oils out there. Have used it in all of our diesels for years, including my 190D for the past 100K +.

Jim

PS - the 300SD will usually be down 1/2 qt between 3K changes,

__________________
2005 C240 4matic wagon (daily driver)
87 190D - 225K (on loan)
85 190D - 312K (on loan)
2011 Subaru Legacy AWD (Wife's)

it sounds like a quality oil. still the problem sounds like it could be lube related somehow.... perhaps because i cant think of any other reasons.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Pulled valve cover; adjusted valves while I was there, oil volume from supply tube appeared inadequate (wasn't quite reaching cam lobes at idle) Chiltens manual indicates problem may be oil pickup tube, guess the pan comes off tomorrow.

Jim

__________________
2005 C240 4matic wagon (daily driver)
87 190D - 225K (on loan)
85 190D - 312K (on loan)
2011 Subaru Legacy AWD (Wife's)

I don't see how a pickup tube problem will cause oil pressure to drop as the engine gets warmer. I would expect a loose or disconnected pickup tube to give zero pressure, since it no longer picks up oil for the pump!

Let us know what you find.

Best Regards,
Jim

the pan is dented up? if so it could be restricting flow. there is not much clearance there.\

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Was your timing chain smacking around?
Make sure you check that out and whatnot.

The pickup screen thingy may be having issues.
Also check the pan.

hmm...

The 617 engine does not have a pick-up tube like the typical domestic engine. The pump itself is in the bottom of the sump.

The pan is pristine, car has been well maintained. Haven't dropped the pan before now so I really don't have a sense how things are set up down there; guess I will find out.

I noticed when I had the valve cover off that the timing chain appears to have a hydraulic tensioner. I can only assume that the chain was slapping around with the low pressure, could have been the sharp rapping noise I heard.

If the screen on the pump were plugged seems as though cold thicker oil would be a problem but the reverse is the case, as it warms up pressure goes down. I could be wrong, certainly wouldn't be a first, but it appears to me to be a supply problem. Either the pump isn't supplying the oil or there is an "open" in the oil distribution system (bad bearing, etc)

My next move is fastlane to have a new pump overnighted; certainly can't hurt to replace the existing.

Thank you all for the comments; keep them coming, all ideas and thoughts are most welcome.

Jim

__________________
2005 C240 4matic wagon (daily driver)
87 190D - 225K (on loan)
85 190D - 312K (on loan)
2011 Subaru Legacy AWD (Wife's)

Is that Mann filter made in Europe or India?

__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

the pan... i suspect blockage rather than oil pump or bearing issues. the bottom ends are extremely robust.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.