I searched the past threads and can't find anything on this, so here goes. My '81 300SD looses power going uphill - it acts like it is fuel starved. I can't say that it would not lose power on the level road with a heavier load on the engine but I cannot simulate that. It falters so badly that the car must be stopped on the upgrade and allowed to recover before proceeding.

My first thought was a dirty or clogged fuel filter, but installing a new filter made no difference. The primary filter is clean also.

The car acts normallly otherwise. Acceleration is good, and it runs fine on the flat.

i am reluctant to tear into the fuel system with my sketchy knowledge of where the problem might be, so has anyone else had this problem?

Any comments are greatly appreciated.

have you inspected the filer at the tank? also known as the tank strainer. it is connected to the feed hose that exits the tank. here is a link that may help you in your diagnosis.
http://www.peachparts.com/shopforum/showthread.php?t=141211&highlight=tank+strainer

Try cleaning your banjo bolts

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1989 300E 144K

Thanks for the comment. I didn't know there was another filter on the line. There appear to be two feedlines that go to the tank. I traced them to the tank and cannot see any filter in either of them.
Approximately how big is the strainer/filter??

it actually screws into the tank, the tank will need to be drained to replace it. there is a large flat socket that is needed to remove the old one i believe the socket is 46mm. not sure what your abillities are, . if they are limited, you may need to take it to a shop and have them do it. some times if you get lucky when you try to loosen the fuel line fitting that attaches to it,
it will loosen the entire unit. to find the unit look on the passenger side near where the right side axle goes in to the differential. it is straight up from there

iwould try using a fungicide on the tank. if it has fungi in it it would act like yours. usually it will show black dots in the small fuel filter, but it is possible that the strainer is clogged with it. draining the tank to take out the strainer is a lot of bother when the fungicide will often do the job wo doing it.

and not much else will clog the strainer that i know of.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

i personally have never used a fungicide, what happens to the debis? are they consumed by enzymes? if they are, then that would be a much better way, one way i have found to tell if the strainer is plugged is whan you rapidly pump the hand pump if it sticks or is held down by suction the straine/filter is plugged,

Well, thanks for all those comments. Finally got the problem fixed and you saved me some time. Just wondering now, regarding the tank filter, couldn't that be checked by blowing on the end of the fuel line where it enters the first filter? that would clear the tank filter temporarily too, probably long enuf to test whether or not it is the problem.

regards, rayquist