Hello again,

I have been trying to get a handle on the issues with this car and I suspect I will need quite a few parts (A/C compressor, air filter assembly, rear window motors, generator and many interior parts). I have been seeing quite a few references to 123 or 126 style and was wondering (since we never even got an owners manual with the car) what the difference is.

What was the last year for the 5 cyl. diesel used in the 1979 model? I keep hearing that "the older diesels were bulletproof - million mile cars" but that the engine was changed sometime in the early 80's. Is this true?

On the vehicle we received, there was an aftermarket fuel pump installed. It is an "Automotive Fuel Pump" model # E8012SM and is marked for 5.5-9 PSI. AmIjust being paranoid about the work Green Benz did or am I right in thinking that diesel fuel would require more PSI to function properly? The car does not have any acceleration and takes several miles (and a downhill run) to get up to 65mph. It feels like the flywheel is the only thing keeping me going! The engine "appears" to have good compression and only "smokes" a little on start up but I won't know until I can get it roadworthy and in to a mechanic.

Thanks for your help,
Between us we'll get this thing purring................................
Ian

 

The engine itself is the same going from the 1979 Mercedes through the early 1980's although the linkages/air filter etc. are different.

Yes, the engines can easily get million miles.

Yes, it sounds like your car was converted to WVO or VO so they installed a fuel pump to increase the pressure.

However, my first guess is that you have a clogged fuel filter. Replace both the In-Line fuel filter (located just before your fuel injector).

More likely, it is the screw on type (looks like a traditional oil filter) located just behind the power steering pump. It sounds like the engine is just not getting enough fuel which is why you only go fast going down a hill.

The next thing I would check would be the fuel injectors themselves. They are not as hard to change.

I recommend that you do this work yourself as taking the car to a mechanic gets expensive. It makes you knowlegeable, and really is not hard. I have found that for most fixes, it takes less time to do the work yourself than the time to drop the car and wait a week+ for a mechanic to work on and then get the car back.

PS: depending upon where you live if you don't want the car I may be interested.

Ohh, and the difference between the 123 and the 126 has more to do with the slight changes in the car body (not the engine).

Good Luck

 

DEAR FORCED INDUCTION
DO YOU REALLY BELIEVE THAT VEGGIE OIL HARMS THE ENGINE? I HAVE SEVERAL FRIENDS THAT HAVE BEEN DOING THIS FOR YEARS WITH NO BAD EFFECTS TO THERE ENGINES I MYSELF HAVE DONE IT WITH MY CUMMINS AND MY MERCEDES FOR THE PAST YEAR AND HAVE NOT HAD ISSUES EITHER ! SO WHAT IS YOUR PROOF THAT IT HARMS THE ENGINE ???

 

I can happily state that I have owned Mercedes for many many years.

Here is what I know I owned:
1975 Mercedes 240D - Total Miles = 600k when I gave it away to a guy because the body just rusted through and gave it away to a guy who drove it 5 yrs
1981 Mercedes 240 D - (wifes car)Total Miles 800k++ but had to give away cause the body got so bad living in a cold climate with the salt.
1983 Mercedes 300SD - Only 500K before the mechanic overfilled the transmission to the top and was driven 20k miles, trans went and I use it as a parts car
1980 Mercedes 300SD -Has well over600k miles on BOTH the original engine and Transmission.


(note: I typically buy them at apr. 300K miles, I put over 80K miles/year on my car) not including my family uses on their car.

Maybe others aren't so lucky.

 

Apr. half of the miles that I put on are highway. I do usually try to find cars that have one previous owner (and typically can tell if they have abused the car). I am selective.

I just pulled my 1980 300SD into a 7-11 last night. 2 guys kept going around who is driving that car. They love the car. Rust is just starting to show but they kept saying how awesome it looks for 600K miles. This one has been amazing. I haven't done anything to (except fuel filters/oil) in past 5 yrs. (ohhh, and adjust the valves now 2/yr (takes1.5 hrs to do) and typically go through two sets of used tires @ $25./tire installed per year). Ohh, yes, I replace the bumpers in the steering. Starts right up in 10 degree F days!

I am putting the 1983 engine in the 1979 car, job almost done.