My 260E has some slight scoring on the cam and the rocker arms

I have read that the early 103's have a soft cam + rockers that were updated according to the FSM in mid 1989, but it requires matching cam + rockers.

So if I managed to find a good looking, low-mileage updated 3.0L cam + rockers at the junkyard would it fit?
Would there be any benefits/drawbacks to using it over a 2.6L?

Thanks,

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

I dunno the answer to your question, but without such a swap just make sure to use oil with zinc additive.

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-tp


1990 300SE "Corinne"- 145k daily driver - street modified differential - PARTING OUT OR SELLING SOON - PORTLAND OR. AREA - PM ME FOR DETAILS
1988 560SEL "Gunther"- 190K passes anything except a gas station
1997 S420 - 265k just bought it with a rebuilt trans. Lovely condition

I just got the valve stem seals done, so assuming its still not burning a quart every 150mi then I will be getting Rotella-T 15-40 changed ASAP. I hope it will clean up the 'red' valvetrain a little better than the current 10-40 I am using.

So, based on that I know about the differing cams now, would it be safe to say that Dino oil should absolutely be used in any early 103 using the earlier tin-plated cam design? Is it still recommended on the updated design too? Just so I know for future reference and knowledge.

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

use 0w-30 for 500 miles, twice or maybe three times. heavier oils don't clean as well as light oils.

but it really doesn't matter, change your hot and often and you'll be fine

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Current
2006 E320 CDI, 57K bought at 67K "Liesl"
1986 190E 2.3-16, 198K bought at 56K "Brigitta"
1987 300TD (Chuggin Along), 292K "Friedrich"
1995 E320 Wagon, 200K "Louisa"

Past
1987 300SDL, (sold) 125K, bought for 1$ "Kurt"

No difference in camshafts in 2.6 or 3.0 liter M103 engines.

Using a 10W-40 or 15W-40 doesn't matter in So Calif.

However the lighter weight oil will allow better lubrication in cool weather.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Thank you guys that answers my questions. I'll keep my eyes peeled.

__________________
2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

I read somewhere that in 1989 MBz changed the camshaft profile for a smoother idling engine (M103), as the earlier cams were known to idle a little rougher than the new ones. That may be what the FSM is referring to in the mid-1989 production change that ps2cho mentioned. Does your response above mean that a 89+ cam (and rocker arms) can safely be used in a pre-89 M103 motor, or only that a 2.6 and a 3.0 use identical cams, provided they are of the same model year?

__________________
1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't

For all USA M103 (2.6L or 3.0L) engines.....the camshaft part number is 103-050-64-01.

OF course that number has "many" earlier versions & requires MANY additional parts on pre 1990 cars.

So a camshaft & rocker arms from any M103 will "fit" into any other M103.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

I'm trying to figure out if I can put a cam, bearing caps and rockers I got from an early 1990s 300sel 3.0 into my 1990 190e 2.6L. I ran out of oil driving up i80 on my way to Reno. Luckily I pulled over quickly before any major damage was done. When I got it home I put oil in and started it up, the engine nock went away, after taking the pan off and plastigauge the crank shaft clearances found it is still in tolerance.

It's obvious that someone had worked on the engine in the past it looks like the exhaust side of the head was machined so the S stamped in the side of the head is missing so I can't tell if it has a hardened cam or not. I also found that the bearing caps had been installed in an incorrect order the worst being #1 was on #6. #6 had a huge chunk of metal missing from right beneath the exhaust side rocker. The aluminum pieces where found in the oil. The cam is scored at the bearings . I need some advice , thanks

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1969 230 inline 6 dual carb 60,000 Miles 2nd Owner doesn't run right
1982 300 SD 455K - my reliable commuter car
1990 190E needs new crank shaft ran it out of oil
1996 C220 bad wiring harness