1977 300d loss of power issues?
 

I have a 1977 Mercedes 300D. Despite hundreds of dollars in repair work the car continues to frequently and abruptly lose power as I am driving eventually coming to a stop. Then I cannot restart it.
Upon examination the inline fuel filter was found to be severely clogged with black gunk. It was replaced and the car ran fine for a couple of weeks. Then happened again. I had the fuel tank removed and cleaned. Of course the main fuel filter [which was severely clogged also with black gunk] was cleaned as well at this time. The car drove well for about 100 miles then, while driving on the highway, it again lost power and died. After the inline fuel filter was changed it drove fine again for 50 miles or so then the filter had to be changed again. I did this for about a month but the times between changes was becoming shorter. So I took it in and the mechanic again removed the gas tank, cleaned it with a solvent and replaced all the filters and hoses. He said the fuel filter was clogged and did get some debris out of the gas tank. He assured me that he “blew out” or cleaned everything as well. He did NOT put the inline fuel filter back on the car however. He had seen an air bubble resting just outside the inline fuel filter and stated that the filter was causing an air bubble to form which could cause or contribute to the problem in the fuel line. That night on my way home the car died on me. It was towed in and the mechanic worked all day looking for an air leak. He found a small hole in a hose and replaced it. II asked him to put an inline fuel filter back on which he did. I again took off,.


I drove about 20 and the car died again. We replaced the very clogged inline fuel filter and drove another 5 miles before it died again. What to do? Thanks.

thanks. I will do that. So you think the problem is in the gas tank? Should I get a new one? since it was already professionally cleaned -twice. Does the car need to have the small inline filter on or was the mechanic correct?

Thanks so much for your help

Now it all makes sense. After reading what you wrote I understand why you advised to have the tank professionally cleaned, use an antialgae chemical and change mechanics, I will take your advice. Thank you so so much!:)