at the bottom of the carb of my W123 M115, there is a hose that connects it to the diaphragm for the fuel return valve (at least that what the book describes it) to another point on the carb (which i'm not familiar with)

what i do know is that with that hose disconnected from the diaphragm, fuel drips down from that point but the car idles nicely.

with the hose connected, the engine sputters and can't hold idle well.

what does that connecting hose do and can i just plug the two points that the two hoses connect to stall for some time till i find another carb?

tks.

Sounds like the rubber o-ring/seal/diapragm is leaking. It may run ok now with it unplugged, but it will only get worse. Time to repair it before you get stranded, or worse.

------------------

thanks for the response. so i presume that the hose at the bottom of the carb is supposed to be a vacuum hose that operates the fuel return valve diaphragm, and that nothing is supposed to leak out of there right?

think the "extra" fuel is going into the vacuum hose and into somewhere and that's causing the bad idle....

The diaphram must be bad for fuel to pass through the vacuum line. This extra fuel will definitely screw up your idle.

The part # is 000 071 01 and lists for $2.30 .

------------------
Steve Brotherton
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician

tks steve. will scour my local MB dealers for the part. guess the carb has to be removed to get to the diaphragm?

hopefully i can get the part. the parts shop here doesn't list it though, just wondering if i can mail order it if i can't find it locally.

where can i get the above part - the fuel return valve diaphragm for the Stromberg 175CD carb? I can't find it locally, and it seems easily accessible and easy to replace. Any help appreciated. Thanks.

Is the part number 115 000 071 01 ?