Perfect Running 300E?
 

I was just wondering...does anyone out there know what it's like to have new or have a 300E that runs like it did off the assembly line (anybody own one of these original)? I have seen pictures of some very sweet 300's with rebuilt bodies and interiors but what was this thing like brand new with regards to starting up, engine idling, acceleration, and ride? With all of these parts and adjustments to check and replace, I would think someone would still have a pretty decent running, very good idling, example (but then, they might not need this forum).

i drove on a few weeks ago with 35k original miles...it was a 1993 with a 2.8 104 engine...

i thought i was going to be able to buy it off the guy... but i guess he changed his mind...

it was the tightness of the suspension and handling that impressed me the most..

Agree with lee on this ....

The biggest issue is the suspension. A friend of mine has a 1991 300e. she had the rear end links, sub-frame mounts, and control arms replaced at the dealer + front control arm bushings.........new Michelin MMX tires and new bilistien struts....(cost a fortune of course)

I drove that thing on the highway at 100mph without knowing that i was at that speed...the 103 is just one of the smoothest engines i have ever seen ........smoother than my 104 ...i loved every minute of it, and the confidence and feel are at sports-car caliber ...

Mine is letter perfect!
 

I have an 86 300E with a manual 5 speed. I replaced the engine with a moderate mileage 89 M103. I pulled and replaced the engine myself and the engine was purchased from member mechanic John Hef. The engine and drive line perform like new. It starts and idles perfect regardless of out side temperature or weather. The performance is simply awesome! Fuel mileage isn't great but acceptable and I drive it 50 miles a day, 5 days a week, except when there is snow on the ground. When I installed the engine I put in new plugs, wires and rotor and 5 / 40 Mobil One. I love to drive it, but this winter at about Thanksgiving I am going to garage it for the winter. We have a decent 94 TownCar that is quite suitable for snow and slush and salt and ice. It is a great car also, but can easily be replaced at any time for less then $1500.00. My two Mercedes need protection from the winter

I do....

Took delivery of my 1988 300CE in May of 1988...
About $53K out the door...

Surprising how quick the stock M103-12V with a 3.07 rear gear is in the C124.
Very smooth power delivery and above average handling and braking..

My personal opinion is that the M103 is a much more responsive engine then the M104.
My comparision is with a 94 E320 Cab I bought a few years ago ..one owner 45K miles dealer maintained...

65K miles later in early 2008 installed a period twin turbo kit from TurboTechnics along with Sportline type suspension mods...

Now in the process of building a tribute to "1AMG" C124 widebody built by Stratton's UK.

The 124 new was an incredible car...well maintained they really don't lose much...!!!!

Wow! Those are some great replies! Especially the 88 300CE brand new. I bet that was one of the top cars back then. Thanks. I wonder how these engines and idles get so out of whack with the rest of us?? I've literally replaced everything I can beside the engine and once I think I have it purring, boink! Something changes and I'm fighting the idle/surge/start problem again. Anyone that had this engine newer ever notice the first things to start causing these issues? I'm of the mindset that it has to be fairly simple since these are built so well. My engine is very strong with 185K and Transmission is super tight. Would like to turn back the clock and ride in one of these cars brand new:) I've had mine for a year and fight with it on and off. I do like working on it though.

I have owned 4 124 bodies ranging from an 88,89,90,2x 92's Great solid cars but like a bank vault and always underestimated.

When they're good, they're really good! I love the German engineering concepts:) I have heard and read not to buy later model MBs. was thinking of a 2003 or later model now. Tired of fiddling with this one and not enough time. Some lucky kid can buy it off me and work on it. What do you guys think? Should I or shouldn't I and if i do, what suggestions do you have?

The main cause of idle / performance problems with the M103 is the deterioration of vacuum lines.
Even the boot between the air valve assembly and the throttle valve gets brittle and leaks.
Suggest you smoke test the engine...amazing where you'll see smoke pouring out....

My 88 300E never was 100% but I love that car! I will keep chasing these issues it has forever. Tell me more about the smoke test.............I would love to find all those vacum leaks:D

I think it must be something with the cams when they get old. I had one that I tried everything and couldn't get it to idle smoothly. I think you just have to learn to not let it bother you, because it really isn't that big a deal.

RBYCC...I think I know what you are talking about. I saw that boot today and thought' "Hmmmm...that looks like rubber and could have leaks". I replaced all vacuum lines and rubber tube connectors months ago. Today I cleaned the idle control valve and the tube that comes off the throttle body was cracked where it connects to the valve. I need a new part but was wondering how the heck I would put it on without removing the throttle body assembly. So for now, I cut it, and used a hose clamp to tighten it on and seal any leaks around the neck. Never thought about a smoke test. Good idea. Tonight I got it running better by opening the lambda Clock Wise. I may have had it to lean. We'll see tomorrow how it does on the 45 mile trip in 100 degree weather (It's usually OK when it's cool out except for when it rains...tough to start).

sptt, hard starting when it's raining smacks of deteriorated ignition wires. When were the ignition wires, distributor cap, distributor rotor and spark plugs replaced last? Spark plugs should be replaced every 30,000 miles in your 1991 300E, and the distributor cap and rotor inspected and possibly replaced.

In 1985 dad bought a 1985 500SEC that I drove around when I turned 16 - Dad went out of town a lot on weekends. My best friend's father bought a 1986 300E the day they came available. Both smelled wonderfully of new leather, they were fast for the day, and, as mentioned, the suspension was firm and solid.

I bought my 1985 500SE with 32k miles on it because it was very close to how I remembered dad's 500SEC. My car is 95% time-warp quality.

My '91 was a joy to drive from new, but by ~60,000 miles it had a hesitation whenever I'd give it a little fuel. Tried all of the normal fuel-injection cleaners (Techron et al) with no change, finally found RedLine which made it run well again.

By 119,000 miles I had a couple of oil leaks, transfer-case re-sealed twice (4matic), a rear wheel bearing, voltage regulator, really not much. Still drove very tight but was only 5 or 6 years old so the rubber bits were quite good.

Used ones I've bought have been a mixed bag. The '94/'95 cars I bought were all very tight, and the extra power that the M104 brings to the table is instantly noticable, nicer steering etc. The early 124 diesels have all needed substantial suspension re-bushing to make them tight, but after all is done they ride and drive pretty much like new, ... for a price.