stuck in New Orleans - PeachParts Mercedes-Benz Forum

farmmedicoh · #1 04-26-2010, 07:59 PM

having "some" trouble with my 82 300sd
just got some welding done on my oil filter stand and while i was messing with it i tried to fix the manual filter which was leaking
wrapped the top (under the white cap) with teflon tape and it stopped leaking
drove it around and everything seemed fine
then the car sat for 5 days
the manual pump doesn't have any pressure at all when i pump it
nothing
at all
got the filter stand welded and now when i tried to fire it up it revs up at first go and then quits
thought maybe i sucked some air into the fuel lines when i removed the manual pump
i have bled the lines from the mechanical pump to the fuel filter and then into the base of the injector(fuel distributor?)
bled fine
the return on the back side of the return bled fine
all of this with the mechanical pump
NOTHING comes out of the top of the injector(fuel distrubutor) or at the engine where the fuel lines go into the motor
nothin
still the rev when i first turn the key and then it dies
nothin

SD Blue · #2 04-26-2010, 08:12 PM

It sounds like the primer pump is still sucking air. (especially since you mentioned the old-style white cap) The problem is how to pressurize the fuel system, driving out the air, without the primer pump. You might be able to use a spare fuel can, placed higher and connected to the input of the IP. Still, you are probably looking at a lot of cranking.

Of course the best scenario is locating a new-style primer pump. Maybe others will chime in here, that are from the area, with maybe a NAPA location that might carry the pump.

kerry · #3 04-26-2010, 08:55 PM

Not sure what you mean by fixing the leak at the manual filter with teflon tape. Can you elaborate on what you did?

farmmedicoh · #4 04-26-2010, 09:01 PM

i wrapped the tape around the top of the plunger just beneath where it flares out
that way when i screwed it down it would have the tape there to block the fuel from leaking out
must have made it mad or something

vstech · #5 04-26-2010, 10:03 PM

tape very bad idea on a fuel system... you have a filter between it and the IP, so at least that's ok, but there is a washer on that pump. if it's leaking, it's leaking on the pump itself, not the connection to the lift pump. just get a new one in there. tape will always leak.

layback40 · #6 04-26-2010, 10:18 PM

To bleed system without use of primer pump (What you call manual filter);

remove return hose from the secondary filter housing (cigar hose)

Carefullyapply compressed air to the return line to the fuel tank (cigar hose). You will hear air escaping from the tank vent, that is ok.

Fuel will in time start to flow from fitting on the secondary filter fitting, best catch this on a bottle.

When there are no longer air bubbles in this fuel stream, quickly remove the air supply and replace the return line back on the fitting. If you are not quick, fuel will come back up the return line & make a mess.

You should make sure that you have at least 1/2 a tank of fuel before you try this and the car is not facing up hill.

Get yourself a new style primer pump from Phil at fastlane.

Good Luck !!

farmmedicoh · #7 04-26-2010, 10:20 PM

yeah
should have just replaced it
thot it worked ok
getting a new one tomorrow
i hope

bobodaclown · #8 04-26-2010, 10:47 PM

Its not just a Mercedes part. Its a Bosch part and has several applications. BOSCH DIESEL HAND PRIMER PUMP

69shovlhed · #9 04-26-2010, 11:28 PM

if you get some of that tape in your fuel system it might clog it up good...
it doesn't take much tape to screw things up.

farmmedicoh · #10 04-27-2010, 10:14 AM

pretty sure the tape didn't break loose and go into the system
i put on a new primer pump
pumped it about 400 times and learned that if i pump it too hard there is some sort of over pressure relief (?)
makes a sort of squishing noise
anyway
pumped it more gently/slower and i could hear it moving fluid
getting good return at the fuel filter on the return line
but still nothing at the injectors
and it still just revs up when i try to start it and then immediately dies

farmmedicoh · #11 04-27-2010, 10:19 AM

for the record
the tape went around the top of the plunger not at the threads where it went into the fuel pump

rrgrassi · #12 04-27-2010, 10:25 AM

Sounds like ther is air trapped in the injector lines. crack open each line at the injector, crank until you see fuel, then tighten the lines.

It seemed like forever to bleed out the air when I changed out the injectors.

SD Blue · #13 04-27-2010, 10:31 AM

I checked and NAPA does carry that primer pump:

http://www.napaonline.com/Search/Results.aspx?Ntt=fuel%20primer%20pump&Ntk=Keyword&N=599001+101984+50044+2044068

farmmedicoh · #14 04-27-2010, 10:50 AM

i did this once om my C30 but maybe i'm missing something

using the manual primer pump....
(the battery is almost dead and i don't have either another car to jump from right now or a battery charger)
i loosen all 5 of the nuts on top of the injectors at once or one at a time?
i removed the nut from on top of the rear injector and pumped about 20x and absolutely nothing happened
i even took off the return line where it goes from rubber to metal and heads back to the tank and put my finger over the end of the hose with the injectoer nut off
the hand pump pressurised the system but nothing came out of the line to the injector
this car ran absolutely fine before i started this process
what i get for trying to fix a small problem

rrgrassi · #15 04-27-2010, 10:54 AM

The primer pump only delivers fuel to the IP. You will not see fuel unless you are cranking the engine.

I know, a dead battery prevents this...