WTB 3 litre diesel mercedes

Geoff wrote in news: snipped-for-privacy@cris.com:

Incorrect! If you change the oil every 3-4K and adjust the valves every 15K you should see atleast 500K! Anything less is unacceptable!!!!

Well, I guess there is a lot of unacceptability with 300D engines. How many mercedes diesels have you seen that made to 500,000 miles without internal engine work? Mine lasted 260,000 miles before it lost enough compression to make it hard to start, this is about average from what I hear from the experts.

--Geoff '84 300D

George Mann wrote:

Well, my unacceptable non-turbo 1980 300CD engine only made it to 208,000 before the timing chain broke. I've put another 60,000 miles on that engine since the rebuild. In all fairness, the cylinder walls were not all that worn when I took the motor apart. I went to the first oversized piston which is

0.25 mm oversized and the crankshaft journals were like new. But I have a 1985 300D with approximately 200,000 miles on it and it still does not burn oil between oil changes. And then I have a friend who drove his 1979 240D to nealy 400,000 miles without any engine work before he sold it. So who really knows how long those engines last?

Geoff wrote in news: snipped-for-privacy@cris.com:

All of [-m,my 300's have made it beyond 500K. They were all original

617's as fitted in the W115's.

In all my years of owning and servicing MB diesels, I have only seen three types of failures within 300K.

One is damage to a motor from excessive lack of oil changes (fairly uncommon).

Another is running out of oil, usually do to a hole in the oil pan (common)*.

Geoff wrote in news: snipped-for-privacy@cris.com:

There are only 3 things that normally go bad on a diesel.

1. Valve seals.
2. Injectors
3. Timing chain/tensioner.

The 3-litre 617's are bullit-proof! All of mine exceeded 500K with only the rubber valve seals and timing chain having been replaced.

Timely oil changes and valve adjustments are the most critical factor in the longevity of a motor.

Also, you will need to use a good fuel treatment/injection cleaner every 6- months.

George Mann wrote in news:Xns9461511BE3DCgmannricochetcom@206.124.0.13:

To continue my involitarily aborted post...

The third is the result of broken timing belts.

The problem I see most often however is tight valves. This results in lost compression, hard starting, and can eventually lead to a valve job do to burnt valves.

Please see my other post.

When I rebuilt my engine at 260,000 miles I found that the intake valve guides were worn out (sloppy!) while the exhaust guides were still good. Valve springs were good. The clyinder walls showed very little wear, so I replaced the intake guides, did a valve job w/ new seals, honed out the clyinders and put new rings on the cleaned and inspected pistons. Now I have all my compression back, it starts in freezing weather with just the glow plugs, and doesn't smoke a bit-- cold or warmed up. The timing chain had previously been replaced.

I'm not sure why the intake valve guides failed, I suspect that the EGR dumping exhaust into the intake might have had something to do with it

*if* the intake guides were made of a softer material than the exhaust guides. Had the intake guides held up better the intake valves would have kept their seal with the seat better instead of dancing around and losing compression. The exhaust valves had quite a bit of carbon built up on them from the low compression. The engine used maybe half a quart between 4,000 mile oil changes so the oil rings held up. Compression (top) rings? I don't know if they were weak or not, but I replaced them anyway as they would have shortly failed with the increased compression after a valve job.

So, would this engine had lasted 500,000 miles with regular oil changes and 15K valve adjustments?-- I have to say in this particular case, no.

--Geoff '84 300D

George Mann wrote:

Geoff wrote in news: snipped-for-privacy@cris.com:

You are right. When a mechanic talks of seals going bad, this includes the possible failure of the guides (50/50 chance).

Unfortunately, no one really knows if or when they will fail.

When I opened my 1980 617 engine after the timing chain snapped, I found cracks in the cylinder head, worn exhaust valve stems, worn exhaust guides, lots of polish on timing chain rollers and just a bit of cylinder wall taper. I was the second owner of the car as I purchased it with 67,000 miles on it. The original owner changed the oil every 5,000 - 8,000 miles. As far as I can tell, the engine was never overheated yet the head developed cracks.

By the way, I have a friend with a 1981 300D and that engine uses a quart of oil every 800 miles. Could that be bad valve seals or? I would like to think the 617 engines are 500,000 mile engines but my non-turbo 617 didn't even come close to your mark. Will my engine make it to 500,000 if I change the oil every

3,500 miles like I've done since the rebuild?

snipped-for-privacy@aol.com (VCopelan) wrote in news: snipped-for-privacy@mb-m13.aol.com:

Hopefully! Be shure to use 15w40 motor oil year-round (I recommend rotella), and keep those valves adjusted (15K).

You know, it's taken 20 years to get 275,000 miles on my '84 300D, by the time it gets to 500,000 miles either me or the car is going to be gone!

--Geoff

George Mann wrote:

Geoff wrote in news: snipped-for-privacy@cris.com:

The less you drive them, the quicker they go bad! ;o)

I've been using 15W - 40 Chevron Delo but according to Chevron it was the first motor oil to make it over one million miles between rebuilds on Cummings, Cat and the other large diesels. Chevron reformulated Delo oil a couple of years ago so I'm too worried. Chevron claims that their Delo 15W - 40 rivals synthetic oil in low engine wear. They also say that the synthetics only exhibit advantages at very low temperatures. I believe both Delo and Shell Rotella are made from type two base stock. And... I like Delo because it's readily available at Costco.

I have always heard the "500,000 mile" ability of the diesel Mercedes engine, but I can't think of the last one I have seen for sale or even one that someone owns or has owned. The reality from what is written here and what I have seen personally is that 300,000 miles is about the most you can expect, and thats with the finest of care. And yes, I know there are the traveling salesmen or taxi drivers who drive their cars 150,000 a year and can reach 500,000 mile with little trouble, but that kind of mileage per year is NOT the norm.

snipped-for-privacy@aol.com (Glenflow55) wrote in news: snipped-for-privacy@mb-m11.aol.com:

Correct. The milage you get out of a vehicle primarily depends on how often it is driven.

The more you drive your Mercedes, the longer it should last!

Ask taxi drivers around the world.

cp