After working all Friday afternoon on my brother's 300SD, I came to this conclusion. We had to change the belts and I was amazed at how difficult that was. V belts suck, especially on that engine, especially if the fine tune tensioners are broken. Also other thing that is bad with the OM617 is that dang Harrison AC compressor, which we couldn't get to work but have hopes for because there was no voltage going to the clutch at all so we are going to trace that fault and hope that compressor isn't seized up (which it probably is).
I just find the OM602 to be easier, with the belt and the much better AC compressor. Of course there are probably many things on the OM617 that are much easier (such as glow plugs) but in terms of that belt, no comparison.

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

Well, yeah, any engine will suck more when it has broken parts!

I found the v-belts to be a breeze when I did my water pump and vacuum pump. I pulled all but the compressor belt and it was no biggie. But then again everything on mine was working!

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

The Baja Arizona Oil Burners Send a message if you'd like to join the fun
Left to Right - UberWasser, Iridium, Stuttgart-->Seattle,, mannys9130

Visit the W123 page on iFixit for over 70 helpful DIY guides!

Figures that 602 is better than 617. It is the later, more advanced version of the same technology.

I totally agree about the belt. I'll take a serp belt anyday.

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Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"

I'm sure they are much easier when nothing is broken or rounded but still too many bolts. I would be able to do it much faster next time knowing all of its quirks but nothing like how quick that OM602 belt is. Now I just wish my 190D had the OM602 turbo so it would have similar power output as the OM617 turbo

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

I agree... Still, the 617 has it's bonuses... They are different, hard to compare the two.

I love my two 190D turbos... I love my 85 SD I love my three 87 TD's... They are all different... They all have huge minuses, and huge pluses...

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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 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

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

Huge plus: my valve adjustment wrenches have been gathering dust since I sold the 300CD. I replaced the lifters in the 190DT after 310K miles, and that's the only time I had to mess with the valves.

I'll agree to the v belts. You have to have a sequence to remove and tighten these for sure. And, serpentine belts are great.
I'll also add that my 84 SD is having ac issues on my compressor not engaging. The 2 sensors on the drier are for low pressure and ambient temp sensor( the red one). Both can be jumped to get the compressor running to at least charge the system, thus finding leaks and such. If both sensors are jumped and still no 12v at the compressor plug, ck the relay in the fuse box, "J" This is what held me up. According to the MB schematics, they did away with this relay for Model year 85. Also, if you jump term 30 and 87, I think, it will energize the compressor. Make sure both sensors are jumped as they are both in series to the compressor. Hope this helps.

As far as replacement I would agree that serpentine belts are awesome. However from a resiliency stand pint I like V belts better as you can have one snap and not have everything else stop working.

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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

If we're talking about refinement and efficiency, yes.
If we're talking about durability and abuse-resistance, ?
I wouldn't blame the engine design for the choice of AC compressor.

Happy Motoring, Mark

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DrDKW

My sentiments exactly. Time for a "Sanden-izing"

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All Diesel Fleet
1985 R107 300SLD TURBODIESEL
2005 E320 CDI (daily)

LOTS of parts for sale!


EGR block kit
http://www.peachparts.com/shopforum/diesel-discussion/355250-sale-egr-delete-block-off-plate-kit.html

1985 CA emissions 617 owners- You Need This!
Sanden style A/C Compressor Mounting Kit for your 616/ 617 For Sale + Install Inst.

Sanden Instalation Guide (post 11):
http://www.peachparts.com/shopforum/diesel-discussion/367883-sanden-retrofit-installation-guide.html

It'll come soon enough and I shall be contacting you at that point lol. Quick question though, is your Sanden kit r12 or r134a?

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

Well certainly the OM617 can take more abuse but the OM602 can last just as long, it'll just need more "babying" such as keeping that cooling system at max efficiency and checking the oil often. Mine with 315,000 miles burns no oil at all between oil changes, and the cooling system atm is perfect. It smokes a bit but I think we have figured out that has something to do with poor injection timing (it was resealed a few years ago by a shop in FL, I have no clue if it they checked the timing or not) or timing chain stretch.

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

The compressors come with oil compatible with 134a, so draining and refilling with ester or mineral oil is necessary if R12 is used.

__________________

All Diesel Fleet
1985 R107 300SLD TURBODIESEL
2005 E320 CDI (daily)

LOTS of parts for sale!


EGR block kit
http://www.peachparts.com/shopforum/diesel-discussion/355250-sale-egr-delete-block-off-plate-kit.html

1985 CA emissions 617 owners- You Need This!
Sanden style A/C Compressor Mounting Kit for your 616/ 617 For Sale + Install Inst.

Sanden Instalation Guide (post 11):
http://www.peachparts.com/shopforum/diesel-discussion/367883-sanden-retrofit-installation-guide.html

The 617 is a more durable engine than a 602, but they are both excellent. V-belts aren't that hard to replace. I did them all on my 300SD about a year ago in about 30-35 mins. Serp belt is easier, but there's more to go wrong, idler pully/bearing....shock absorber...tensioner.....had to replace ALL of it on my OM601 before I put it into service.

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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)

I've almost made the decision to not buy any more vehicles. That would mean finishing the 84 & 85SD, the 00 diesel ram, and the 78 Datsun Z. Currently, 3 0ut of 4 are licensed and DDs. All need some AC work. All have between 170k & 240k on the clock. I noticed a small amount of grey smoke upon acceleration while driving behind my wife who was in the 85SD.

The 78 is the most fun to drive.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.