The engine in a 85 300SD is good for how many miles ?

What are the weak points / critical repair issues angine primarily and whole car ?

( I am assuming timing chain and vacuum pump like the 602 ) anything else ?

thank you

OM617 (the engine in your car) was used is all the 300TD, 300D, 300D turbo and 300SD sedans and wagons from 1977-1985. They are generally reliably driver without a rebuild up to at least 400,000km with many easily exceeding that amount. It really all depends on maintenance. Regular oil changes, valve adjustments, etc. The vacuum pump isn't as big an issue as it with the om60X engines. Timing chain should be replaced when it exceeds its stretch limit which can be measured. basically the statement that these cars will go for a million miles with no maintenance is false. However with some care and attention they can go for a long while.

As for weak pints there are really no specific parts that always fail. Injectors are often neglected, as well are valve adjustments, and glow plugs burn out, but those are common to many engines. As for the car as a whole the climate control system is a weak spot and can be a real pain to get functioning correctly, also motor mounts are a common failure point.

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

Thank you, I was under the impression that these engines might be good for 400,000 miles not km.. as it has 240k miles on it now that is equal to 400K km...hmmm pretty well used up at that I suppose.

thanks

There's a guy on here who ran an OM617 to 1.3 million miles before a rebuild. That is more than you should expect in normal use. Mine is up to 325,000 miles on the original engine and starts the same at 20F as at 80F. A compression test will give you a good idea what's left in your individual engine.

__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

On the turbo version often you need a head gasket at around 275 to 300,000 miles. At that time an examination of the valves for wear and a valve job is a good idea. At that mileage if reasonable care has been given the bottom end should show minimal wear.

__________________
[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.

Thanks,

Not all 85 617 motors are turbocharged ?

In North America only the turbocharged OM617 was sold in 1985, but MB made the non-turbo OM617 for the Euro and other markets up to 1985. Some of these might have ended up in North America through personal imports.

correct, the euro version was still available in N/A in 85. all US 300 series were turbo in 85.

as for the timing chain and vacuum pump. the pump can fail exactly like the 60x series pump does... mine did.
INSPECT IT!!!

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

At 250K, your "inspection" is going to find worn components. Since it went 250K and didn't grenade, consider yourself lucky and replace it or find all the components to properly rebuild it.

Thankyou very much

It is 28 years old with 240 000 miles, nothing is reliable If you want reliable buy a new Japanese with a warranty!

I think by the time you have 100 000 miles you can't gauge much on the miles... there are so many different variables that come in through the middle, like maintenance or driving conditions. Or even failures of the odometer, maybe it reads 240 000 but hasn't counted a foot in the past 10 years of driving. or maybe it counts 10 000 miles for every 10 (it happens...)

I agree with the idea that cars this old with as many miles as we see, you can't judge the car based on the number of miles it has. If a million mile engine has good compression and shows no abnormal signs, I would buy it in a heartbeat. The OM617 crowd averages at least 250K miles. The chassis needs more work than the engine normally does. If the chassis is rust free and has few major issues, I would advise buying the car at a reasonable price. If the engine was severely neglected, you you can find an OM617 at PNP for $250 all day long. At least in my area. I have never seen a chassis with an OM617 where the engine has been pulled in any of the 6 junk yards I visit. Why? Well, it's pretty rare that you need to completely replace an OM617.

There are two tests that I would use to initially evaluate an OM617 engine before purchasing it. #1: How well it starts. #2: The amount of blow-by the engine has.

#1 can vary depending on the glow plug system. None the less, an experienced observer can feel the amount of compression the engine has based on the speed it turns over at and sound/feel of the engine as it turns.

#2 If the oil cap can be loosened and balanced on the valve cover while the engine is running at operating temp, I'd buy it.

Those are the two initial tests I performed on my car before I bought it. It has been my daily driver for over a year now and I have not been stranded once because of any mechanical issue. Flat tires are another story but that was my fault. LOL

__________________
1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

My oil cap sits nicely and vibrates a bit at operating temp, as long as it's at idle. Is that what you mean? When I rev it up a bit, the cap dances around, but not really too much. (215,000 miles).........

__________________
'85 300 TD wagon. Euro spec. 215,000 miles, real beater (for now). '59 f350 with cummins 6at, 54 gmc flatbed with cummins 6at, '92 f350 service truck with 7.3 NA IDI and 5 spd man tran, Grumman Aluminum stepvan with 6.2 (cabinet hauler) I like diesels.....

Compensating for engine vibration, it should not fly off or fall off on its own. I'm not saying that the cap should remain completely steady. It may vibrate with the engine but it should not be flopping all around because the blow by is pushing it off the valve cover. If you see a ton of vapor coming out from under the cap, it may be a concern.

__________________
1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

Not much vapor. I have seen mention of a test to fill a garbage bag with blow-by. As in, if it fills a 32 gallon trash bag in so many minutes, time to worry. Don't think I'm there yet. Starts really well. I'm determined not to worry this time. It's a thousand dollar car I bought from a neighbor on a whim and I'm not gonna worry about anything but the brakes, oh and the timing chain, and the beginning of rust in the wheel wells, and............

__________________
'85 300 TD wagon. Euro spec. 215,000 miles, real beater (for now). '59 f350 with cummins 6at, 54 gmc flatbed with cummins 6at, '92 f350 service truck with 7.3 NA IDI and 5 spd man tran, Grumman Aluminum stepvan with 6.2 (cabinet hauler) I like diesels.....