hello guys, I'm new on this forum, but I love old mercs, especially diesel ones, which are known to be very reliable; the only problem is that I can't find out which, between the om615, 616 and 617 (non turbo), will last longer without major problems; so, if I had to pick between the 200/220d, the 240d and the 300d, which one should I choose? thanks in advance

"the best diesel engine of the 70s-80s?"
Cat 3208

😂
Good guess but false. The correct answer is the Cummins B-series.

That response implies that there was a test of some sort involved, in which answers can only be either true or false.
The question, as framed by the OP, seems to solicit opinions. Is your response the result of a guess or of informed opinion? If the latter, please have the courtesy to credit all other responses as also resulting from informed opinion.

Nah, both you and Frank are wrong. For durability nobody could touch that era of Perkins diesels.

The IHC DT466 was a fantastic engine but weighed 1400+ lbs. which ruled out its use for any light duty applications.

The 3208's had electrolysis issues plus it weighed 1600+ lbs. Great engine for boats or construction equipment due to its economical fuel use.

The early Cummins 4Bt's had problems with their camshafts plus the "Killer dowel pin". I still have four or five replacement dowel pins in my tool box from my wrenching days. The camshaft issues were resolved in the later 80's with a revised turbocharger mounting.

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now

I was being facetious. I love’em all, just can’t afford to have more than three at a time. I recently read an article by the same title as this post. The writer equated the question with asking a mother which of her children she favors most. However, I do think any and all entertaining the question can agree on one thing: It’s got to be a Diesel.

I think(aka MHO) all of Mercedes diesels are great but I’m only familiar with working on the 615, 616, and 647. Excepting the latter(opinion) the early diesels are fun for the beginner enthusiast and professional alike. What makes them great to me:
They’re relatively simple, easy to maintain, fun to work on, parts availability, enthusiast support like this forum, and the fact that despite horrendous abuse/neglect there are so many of them still in service. That makes them great to me.
Can they compete with a modern diesel? In some aspects the answer must be ‘Absolutely’! But to be fair a comparison between an OM617 and a Cat 3208, 71 series jimmy, B-series, et al… that’s just apples and oranges. Diesel technology has far surpassed performance capabilities but operating and maintenance costs…? Yeah those have far surpassed the older OMs on at least the same gradient with performance. I think a great diesel engine is only as good as it’s application. There’s a lot more 616 and 617 transplants than non OEM engines transplanted into Mercedes. I can’t recall hearing of one but i’m sure there out there. The 616 is still produced on license to a company in India for new production cars. Considering the number of choices available I think that speaks volumes. They’re still a cost efficient power plant if you don’t need to pull a house off it’s foundation or break a record a Nuremberg. I expect 616 amd 617 will be around for decades to come. I hate to use the metaphor but these engines(in my experience) are like the unconditional love a dog shows his abusive owner. They live better longer if you treat them like you ought to. Abuse them regular and eventually that dog won’t hunt.

Detroit Diesel 6-71

More important is knowing what you're getting into. They run great until they don't, and it gets expensive. The vacuum pump grenades and takes out the whole engine, the belt cuts through the oil cooler line and bricks the engine, the transmission gives up at 200,000 on the dot, a rod starts knocking all of a sudden for no reason at all...

Lots of scenarios you can read about on this forum. If you don't have a lot of money, make sure you love working on it, love scrounging for parts, and enjoy people in parking lots telling you, "These'll go a million miles!" (After you replace the engine and every other part a couple times over, they sure will.)

If you're going for just straight hard core durability and longevity it would be hard to beat the OM601....but at 72HP it will get you there just not quickly. They are a bit easier to work on than their OM61x relatives but also generally need less ongoing servicing. Mine had 335k+ on it when I sold it running fine, I had replaced the lifters (all 8), injector nozzles (4) and timing chain + vac pump. Could run it at 100% for hours on end and it would happily do it. Car maxxed out around 85-88mph depending on conditions

I'd still rather have an OM617 Turbo however, so much more power, and the sound is awesome....even if it does need more upkeep.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

As bulletproof as the 61X motors are, with the routine servicing needs, my vote is for the 603.
Sure, the #14 head is a bummer when overheated, and sure, the front head bolts in the chain area back out, allowing oil burn… but… overall, the power, sewing machine smooth running, the far easier maintenance… did I mention the power?

Of course, they need the vacuum pump upgrade. They need delivery valve seals every 100K… a #22 head upgrade is a dream improvement (I have one) the serpentine belt tensioning system is kooky… and the alternator really needs more output, but then you have to change to a clutched pulley on it… the stock aluminum fan is too weak, and the 606fan needs CAREFUL attention to prevent flexing into the radiator….
Why do I like it so much again?

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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 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I agree with you the 603 with an update head is the best engine no electronics I own two 603’s my daily driver has 111,500 miles on a rebuilt 603 with a #22 head and after the rebuilt I have done nothing to the engine. And my second 603 has a #20 head I just replaced the head a few months ago and is running great. I’m working on my third 603 to is going to have a #17 head and is going into a W201 190D

I'd vote for the 617 na. The next series I don't have as much experience with. This era is potentially a very simple engine to work on.

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[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.

Consider the fact that this 3.0L NA diesel was originally designed by Daimler as a TRACTOR engine.

It would be the perfect engine for any vehicle that never went above 100 km or 65 mph. Especially with an MT

Does that fit what you do?

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Strelnik
Invest in America: Buy a Congressman!

1950 170SD
1951 Citroen 11BN
1953 Citroen 11BNF limo
1953 220a project
1959 180D
1960 190D
1960 Borgward Isabella TS 2dr
1983 240D daily driver
1983 380SL
1990 350SDL daily driver alt
3 x Citroen DS21M, down from 5
3 x Citroen 2CV, down from 6

Ok, I'll be that guy....

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1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD