M103 shared between models?

1979-1991 280SE, 300SE, 300SEL, 380SE, 380SEL, 380SEC, 420SE, 420SEL, 420SEC, 500SE, 500SEL, 500SEC, 560SEL, 560SEC
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Ozpacman
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M103 shared between models?

Post by Ozpacman » Fri 24 Nov, 2017 9:52 pm

Hi all,

A question for you knowledgeable folk re the M103 engine. I have a '91 300SE which I suspect has a few engine problems. There's an '89 300E for sale locally which runs nice and quietly and has way less kms than mine. I'm confident that I could pick it up fairly cheaply as it has just come off the road and is for sale as is and unregistered.

Can anyone tell me if the same 3 litre engine and transmission was used in these vehicles? I'm thinking an engine swap may be an economical way to go if they are in fact shared mechanicals.

Cheers,

Russ.

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Ivanerrol
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Re: M103 shared between models?

Post by Ivanerrol » Fri 24 Nov, 2017 10:25 pm

M103 six cylinder - one of MB's best engines.
Was used in
W126 300SE, 300SEL, also in 260SE not imported to Australia.
W124 300e, 260e
W201 190e 2.6.

An '89 W124 300e engine is compatible with your car. - Straight swap.
Just make sure the car is not a 300e 24valve.
if you can find out the car's VIN number we can check it for you.

Having said all that, M103 engines are generally very reliable. it's the peripherals that cause much of the issues.
Has the car been overheated and caused a head gasket issue?

There a plethora of parts in the KEJet system which are problematical and cause issues which may seem to point to a faulty engine rather than
problematic ignition or injection system.

If the 300e has many less K's than your car then I would swap the engine and transmission together.
W211 - E240
W204 - C280
W210 - E240
Departed
W202 - C200, C180, C180
W126 - 380SE , 380SE (Ex SA Import), 560SEL
W124 - 300e, 260e (ex Japan)
W111 220s (Indonesia) 4 speed manual column shift
W123 230
W116 450SEL
W140 420SEL
W210 E240
W209 CLK 240
W201 190e 2.6 (ex U.K.)

Ozpacman
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Re: M103 shared between models?

Post by Ozpacman » Sat 25 Nov, 2017 11:26 am

Thanks very much for your reply Ivanerrol. My car is at a small property I own which is about 1400km away so unfortunately I don't have the opportunity to tinker with it. It is not presently running though. I brought the property as a deceased estate and the car sort of came with it. It's a very straight and clean car and I believe is well worth saving.

I haven't had a good go at getting it running as yet, however I did discover it would start and run briefly if I dribbled a small amount of fuel directly into the plenum. This leads me to suspect that the fuel pump is not well. I did try another fuel pump relay however it made no difference.

What I have noticed is that there are some pretty substantial oil leaks around the front and underside of the engine. Recently I was chatting with one of the neighbours who knew the previous owner and the car, and he was telling me that it had a pretty severe blow-by issue. The previous owner had a used car yard and had bought this car at auction with a view to reselling it, and this issue caused him to park it up.

I haven't done a compression or leak-down test on it as yet due to the above mentioned tyranny of distance but this will no doubt tell me more. The car has just over 300k on the odometer so the cylinder head could be in need of reconditioning as well.

This 300E I mentioned has only done about 150k so I'm thinking it could make a great donor car.

Your thoughts?

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MMWA
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Re: M103 shared between models?

Post by MMWA » Sat 25 Nov, 2017 9:44 pm

Speedo on w126's is electronic and mechanical on the w124's,

If you plan on using the w124 transmission this needs to be considered, conversion to electronic will be required, im sure its possible though.
MMWA

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T-Modell
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Re: M103 shared between models?

Post by T-Modell » Sat 25 Nov, 2017 9:51 pm

Ivanerrol wrote:
Fri 24 Nov, 2017 10:25 pm
M103 six cylinder - one of MB's best engines.
Was used in
W126 300SE, 300SEL, also in 260SE not imported to Australia.
W124 300e, 260e
W201 190e 2.6.
...
Not to be forgotten the R107 300SL and the R129 300SL :notworthy: ... smart-ass mode off :laughing6:
Thomas
---------------------------------------------------------------
1967 W111 250SE Cabriolet, horizon blue
1973 W115 220D 5.0 Pick-Up Argentina, work in progress 2017/18/19
1986 R107 500SL, arctic white, the midlife crisis viagra replacement
2007 R171 SLK350, calcit white
2008 S211 E63T, calcit white, sleeper

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Ivanerrol
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Re: M103 shared between models?

Post by Ivanerrol » Sat 25 Nov, 2017 10:01 pm

I put a W126 transmission in a W124 - no trouble with the speedo.

Electronic speedo's didn't come until the W202 and M111 engines installed I thought. But it's worth checking.

F.W.I.W. Electric speedos are run off the diff. So it doesn't really matter what transmission you put in. (As long it's not a 722.4)



If the car has been sitting a long period of time then I'd suggest the car requires new fuel pumps, fuel filters and hopefully not a fuel distributor. The tank will probably need flushing and proabably so will the injectors. There's a fuel tank filter that will require either changing or cleaning.
A known good running donor car will supply most of your bits and pieces.

I can attest to what happens to a fuel pump if left lying around for a couple of years with stale fuel in it.

If the body and interior are in very good to excellent condition - no rust around the rear windows then I wouldn't hesitate to give the mechanical's a go.
W211 - E240
W204 - C280
W210 - E240
Departed
W202 - C200, C180, C180
W126 - 380SE , 380SE (Ex SA Import), 560SEL
W124 - 300e, 260e (ex Japan)
W111 220s (Indonesia) 4 speed manual column shift
W123 230
W116 450SEL
W140 420SEL
W210 E240
W209 CLK 240
W201 190e 2.6 (ex U.K.)

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Ivanerrol
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Re: M103 shared between models?

Post by Ivanerrol » Sat 25 Nov, 2017 10:03 pm

T-Modell wrote:
Sat 25 Nov, 2017 9:51 pm
Ivanerrol wrote:
Fri 24 Nov, 2017 10:25 pm
M103 six cylinder - one of MB's best engines.
Was used in
W126 300SE, 300SEL, also in 260SE not imported to Australia.
W124 300e, 260e
W201 190e 2.6.
...
Not to be forgotten the R107 300SL and the R129 300SL :notworthy: ... smart-ass mode off :laughing6:
Thomas
Thomas, So few of those were sold in Australia I think you would be struggling to find one. :dance:
W211 - E240
W204 - C280
W210 - E240
Departed
W202 - C200, C180, C180
W126 - 380SE , 380SE (Ex SA Import), 560SEL
W124 - 300e, 260e (ex Japan)
W111 220s (Indonesia) 4 speed manual column shift
W123 230
W116 450SEL
W140 420SEL
W210 E240
W209 CLK 240
W201 190e 2.6 (ex U.K.)

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MMWA
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Re: M103 shared between models?

Post by MMWA » Sun 26 Nov, 2017 9:23 am

Ivanerrol wrote:
Sat 25 Nov, 2017 10:01 pm
I put a W126 transmission in a W124 - no trouble with the speedo.

Electronic speedo's didn't come until the W202 and M111 engines installed I thought. But it's worth checking.

F.W.I.W. Electric speedos are run off the diff. So it doesn't really matter what transmission you put in. (As long it's not a 722.4)
What did you connect the cable operated speedometer shaft in the w124 onto on the w126 transmission with ? All w126's have electronic speedometers.
MMWA

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MMWA
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Re: M103 shared between models?

Post by MMWA » Sun 26 Nov, 2017 9:38 am

Looked at the epc.

Rear transmission housing on the w126 is missing the big drive gear on the out put shaft and the gears that mesh to it to the also missing speedometer output shaft on the W126 transmission.

transmission donor from w124 to w126 wont be a problem the extra parts wont be used.
transmission donor from w126 to w124 would be a problem and the extra parts would need to be installed.
MMWA

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AMG
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Re: M103 shared between models?

Post by AMG » Mon 27 Nov, 2017 4:42 pm

Ozpacman wrote:
Fri 24 Nov, 2017 9:52 pm
Hi all,

A question for you knowledgeable folk re the M103 engine. I have a '91 300SE which I suspect has a few engine problems. There's an '89 300E for sale locally which runs nice and quietly and has way less kms than mine. I'm confident that I could pick it up fairly cheaply as it has just come off the road and is for sale as is and unregistered.

Can anyone tell me if the same 3 litre engine and transmission was used in these vehicles? I'm thinking an engine swap may be an economical way to go if they are in fact shared mechanicals.

Cheers,

Russ.
Same m103 engine - just keep your trans & converter. i.e. engine-only swap.

be careful of thermostat housing exit and water pump outlet routing. should be OK, but been a while since I looked at a 6 cyl 126.
Current:
1987 560SL 4sp. auto Signalrot "Stella"
1987 190E 2.3-16 5sp. man. Blauschwarz "Hermann"
1992 300CE-24 6sp. man. Perlblau / Iceblau "Gretel"
1992 Range Rover Vogue SE 4sp auto Ardenne Green "Oswald"
2012 Renault Sport Megane RS265 Trophy 8:08 6 sp. man. Liquid Yellow "Jean Rédélé"
Previous:
1986 560SEL Anthracitgrau "Schultz" - In Mercedes Heaven
1987 190E 2.6 4sp. auto Signalrot "Sabine" - which now resides/owns Andrew M's Garage
1972 350SLC Astralsilber "Lurch" - now in the loving care of Craig B
1989 2.5-16 Blauschwarz 4sp. auto (parted) formerly owned by Derek/Hasan.

Ozpacman
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Model you own: w126
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Re: M103 shared between models?

Post by Ozpacman » Mon 27 Nov, 2017 5:31 pm

Thanks for all your replies gents.

Unfortunately the donor W124 idea didn't come to fruition. A third party told me it was a good smooth runner however when I spoke with the seller he told me it was down on compression in several cylinders. Turns out the 150k on the odometer was most likely the second time around so at 1.15 million kms she's more than likely ready for the scrapper.

I'll be sure to take my compression tester on the next visit to the property and that should give me an idea of what I'm looking at with my engine.

Russ.

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AMG
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Re: M103 shared between models?

Post by AMG » Mon 27 Nov, 2017 5:34 pm

Russ, when you really only need an engine, why bother with a whole donor car??

What other items do you think you'd like to 'swap' out?

I ask this because in reality it's a lot easier to just grab a running engine. No hassle trying to dispose of the other bits and pieces as well.

Unless you want to offset the cost of the engine swap by parting out a donor - which becomes a hassle unless you have a lot of covered space for dismanting and storage.
Current:
1987 560SL 4sp. auto Signalrot "Stella"
1987 190E 2.3-16 5sp. man. Blauschwarz "Hermann"
1992 300CE-24 6sp. man. Perlblau / Iceblau "Gretel"
1992 Range Rover Vogue SE 4sp auto Ardenne Green "Oswald"
2012 Renault Sport Megane RS265 Trophy 8:08 6 sp. man. Liquid Yellow "Jean Rédélé"
Previous:
1986 560SEL Anthracitgrau "Schultz" - In Mercedes Heaven
1987 190E 2.6 4sp. auto Signalrot "Sabine" - which now resides/owns Andrew M's Garage
1972 350SLC Astralsilber "Lurch" - now in the loving care of Craig B
1989 2.5-16 Blauschwarz 4sp. auto (parted) formerly owned by Derek/Hasan.

Ozpacman
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Model you own: w126
Location: Trinity Beach Qld

Re: M103 shared between models?

Post by Ozpacman » Tue 28 Nov, 2017 5:49 pm

Hi AMG and yes, you bring up a valid point. Fortunately for me though, the new man-cave is a commercial size shed which is a tad over 400 square metres under roof so I have no shortage of shed space.

With this in mind I thought it might be better for me to try and get a complete car and then dismantle it.

Russ.

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ngruzevs
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Re: M103 shared between models?

Post by ngruzevs » Wed 29 Nov, 2017 6:22 am

To be honest good 300SE'/SEL's are not that expensive. One of my friends purchased this 87 300SEL in Vic for $5K, it included a RWC and had 6 months reg.
23794929_1707474482625692_8973400887409658780_n.jpg
This 300SE was sold at Shannons on Monday night, had 117,000 on odometer and sold for 6.5K.
1987-mercedes-benz-300se-saloon-5.jpg
I assume your car must be worth saving, e.g. exterior paintwork and interior must be very good?
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1971 MK2 Jensen Interceptor Regency Red Jeremy
1985 W126 280SE Thistle Green Max
1987 W126 300SE (SA Delivered) Pearl Grey Matt Oscar
1990 W126 420SE Dark Blue The Gangster
2013 MK7 Golf GTI White Gerhard

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