Help....85 Mercedes 300SD is losing fuel prime

After it sits for a few hours, I think the fuel is draining out of the fuel rail and pump, so I have to manually prime it to get it going again. There is a clear in -line fuel bowl right next to the pump/primer, and there
was only a little fuel in the bottom/lower end of it (the end away from the pump& engine). I checked the fittings on the fuel filter, the seal on the hoses, clamps on the fuel bowl, etc. but cannot see anywhere it might be sucking air...so I think the fuel is just draining back into (or towards) the fuel tank. Do I have to replace the whole pump, or is there some o-ring seal or check-valve that I can replace to fix this?
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The first thing you will want to do is get the car on a lift and check all the fuel lines.
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There's an air leak somewhere between the fuel pump to which the hand primer is screwed and the injection pump.
I believe the hand primer pump is the culprit; it has a non replaceable seal under its handle to seal its plunger. A replacement primer pump costs about $20 on-line and is a DIY job.
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I find that my hand primer pump handle tends to migrate loose - checking it and retightening it every other day seems to minimize the lake under my 300 SD.
(TG - thanks for your earlier advice regarding electricals. I discovered that my trunk light stays on all the time, resulting in a 4 amp draw on the battery even when the car is not running - SdSD.)
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I had the same problem, really confounded me. Left me stranded a few times too. Finally I discovered that the fuel line connection to the feeder line on the bottom of my fuel tank had age cracking, was letting air into the line.

there
the
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hi group, new to this group, need info help. thinking to get 380 sl or 450sl and if you know this car is realiable or not and expensive to maintaie it?,pleas let me know. I have 89 vette thats been great but too hard to drive (I use wheelchair) so thinking about SL but worth getting it or am I looking for problems? you would think vette would be problem car but its not...just bitch to drive and get in/out if you are disable...lol
any info would be great help...
and if you are interested in possible to to trade with clean 89 vette, e-mail me please
thanks much
tom snipped-for-privacy@charter.net
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A really good 380SL can be economical to own and drive. As far as thehandicap, it can;t be much better than the Vette. Perhaps a 300CE coupe or so might do it.
Bill Ditmire Ditmire Motorworks,Inc. 425 White Horse Pike Absecon,NJ 08201 http://www.ditmire.com 609-641-3392
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A 450SL in the proper condition will most likely be the most reliable you will ever own.
Cost of ownership is directly influenced by controllable external factors.
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tom, i have a classic 1973 450sl black on black, not sure if you want a everyday car or a special car for special times. if interested call me at 5029628409 at my store. thanks, jim

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