we have had the car a few weeks and have had no problems with it at all. everything works and it starts right up and shuts down evertime like it is supposed to.
My wife was driving the car on empty (reserve light on) and she stopped at the mall, for about an hour. she went back out to come home, backed up a few feet, it died and it would not start. thinking it may be out of gas we had it towed it to the gas station across the street and filled the tank up; no change. Towed it home, and have tried swapping filters, getting new lines and new clamps. Even tried the injector purge/clean instructions i found on the internet, and it still would not start (with just the purge tank hooked up. completely bypassing the gas tank and all its lines!)

the only time it tries to start It just starts after sitting overnight for about 10 seconds and sputters and coughs to it's death. Verified all the vacuum lines are connected and the hoses are in great shape. No leaks from the bypass lines at all or any where else I can see. I bypassed the fuel thermostat thinking that would make the fuel too warm in the 107F heat. I tested the automatic primer pump and it seems to be pumping , although i connot get any reading of pressure from the pump when cranking the engine. i do get a little fuel at the injectors when i crack the lines open and crank the engine over.
Any ideas what to test next?

Sounds like you still have some air... mash the pedal as you crank it. The 603 doesnt have a manual pump so you have to turn it over several times to work the air out. You were probably close, but having opened it up again and again you were just reintroducing air.

Zack

ok. i have gotten all the lines and filters replaced. i see no bubbles anywhere in the clear lines and every time i have cracked a line i get fuel, no air bubbles.
however i have cranked, and cranked, about 50 times and still it will not start. it seems to almost start, but it sputters out in a few seconds.
i have also tried a little tiny bit of starter fluid sprayed in the vacuum hole below the intake manifold pressure sending unit. but all it did was bang pretty hard.
please note this is in arizona, and it is 107 today, so i cant imagine that the glow plugs would even be needed, but i have not tested them at all. the glow plug light does come on for about 5 seconds, and it seems to try harder to start, but doesnt really make any difference. i have also tried cycling the glow plug, 3 or 4 times, then trying to start it, but it made no difference.
also as some background the person i bought this from drove it for a while with a badly leaking turbo, so everything is full of oil in the intake system. the vehicle does not smoke since the turbo was replaced, and cleaned the initial oil out of the system. we drove it problem free for 600+ miles. then, it just died when the fuel tank was near empty, the low fuel light had just come on.
i have checked the tank screen, and also tried reversing the supply and return lines with no difference.
any suggestions? ideas?

Explain how you tested this pump. This engine has no primer pump. There is a main fuel pump down on the driver's side of the engine. The pump is between the primary and secondary filters.

BTW, don't do that.

i followed the instructions from the mercedes manual i have that tells me to measure the output of the pump into a container that i can measure. i did this and got just a little more than spec. i got 180cc/30seconds and the spec is 150cc/30seconds.
so it said i did not need to go on to test pressure.

as for the starting fluid. i used no more than 1/2 cc total. i have read it posted no less than 5 times to this forum, and many times in others to use just a tiny bit to kick the combustion up a bit.

since i have been cranking it for a week i figured it would not hurt once. i appreciate any input since this is our only car.

so what next can i do without starting fluid.

When you changed the secondary, did you fill it completely with fuel before securing the bolt?

yes. i also didnt tighten it all the way and cranked it until fuel started coming out of the rim of the filter and tightened the nut up.

Have you cracked the injector lines to make sure you are getting fuel to them?

What about hooking a fuel tank directly into the lift pump? This way everything is bypassed. Lift this tank pretty high to, let gravity work for you. If that doesn't start it I would start to think about internal IP issues or some sort of timing problem.

What about taking off the hard lines and cranking. A healthy IP should shoot fuel pretty high and make a bit of a mess. A not so healthy one may only trickle.

With temps that high forget about the glow plugs, even if every single one was stone dead the engine would start.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

so the lift pump is what i have been calling a fuel pump?

i have read from a few places not to disconnect all of the injector lines at one time that it may mess with some timing or other and if it does that then you cannot shut it off until it blows up?
can i just crack one at a time and floor it while starting?

also with the idle control, is there any chance i could have messed up the IP by adjusting the idle by releasing the locking nut on the adjuster and turning the center bolt counter clockwise to adjust the idle speed up to about 750? it was just over 500 and if you floored it and then let all the way off it would die.
is there any way this could have caused my issue, as i did it just a few days before the car stopped starting.

thanks again for any help.

narftroz,

Its a fuel pump, it pressurizes the IP. A lift pump just lifts the fuel usually to a carburator, a non pressure operated device. The IP needs fuel pressure to push the fuel into the barrels.

U can disconnect all the injector lines at once. It won't affect the timimg and the engine won't run away. Each of the outlets of the IP should squirt fuel high enough to hit the hood. If they don't squirt, then that is your problem.

P E H

...........if the intake manifold wasn't in the way............

now dear old dad 20 mercedes diesels later would say you get what you deserve with a 350 worse engine mercedes ever built but thats just dad

__________________
commercial fisherman diesel in my blood in my boats trucks and Dear old Dad has had me drivin them since i got my first license in 1968
1986 300 SDL 427654
1999 Chevy Crew Cab Dually 225423
1986 300 SDL 287000 Dad's
1987 190 Turbo 158000 Mom's (my inheritance)

I think hes asking for some help not opinions on his motor.Have you ever run the tank that low before ? I am not sure if this applies,maybe Brian can help here,I remember a similar peoblem last week on a 300sd and it was a tank vent problem,he removed the fuel cap and was able to start the engine,again not sure if it applies to your engine,best of luck .

__________________
85 300sd SOLD ,85 745i,95 740i,1972 Suburban,1938 International

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