So I'm troubleshooting what I believe to be fuel delivery problems. I filled it up and drove to work. Halfway home the battery was dead and it wouldn't start after I stopped to get a coffee (this is only the second time i've gotten the car to drive by the way so i'm still very unfamiliar with it). Put in spare battery, made it the rest of the way home (round trip 60 miles) and it never started again. Turns over but won't catch.

When I crack the injectors I can't get more than a drop. When I unscrewed the fuel filter I got a long loud hiss and could hear air getting sucked in and gas falling back to the gas tank. Lasted probably 30 seconds

Maybe just drove in on fumes and I didn't know? Gas gauge said I had only used 1/4 tank.

1) How big is the gas tank on a 240D?
2) What sort of gas mileage should I expect?

Also, when I replaced the fuel filter I found a metal washer that I"m pretty sure had been between the filter and its housing, the size of the bolt that holds it in. The new filter didn't come with any washers. The housing arleady has a rubber gasket. Should I be putting that metal washer in? I'm also wondering if I am getting air into my lines somehow and thought maybe this would be a reason?

Probably all pretty basic and stupid questions but you gotta start somewhere....

You should be getting right around 30mpg in a 240. Some get a little more, some a little less. There should be a crush washer under the bolt head that hold the filter to the filter stand. Usually you can get away with reusing it several times as long as it's not totally mangled, but they do need to be replaced every so often.

The sucking sound makes be think you have a clogged tank vent. If you can get it started again, let it run for a while, then pull the fuel cap off. If you get a big suction sound your vent is clogged. There is a little bell shaped rubber end on a steel line at the rear of the car, I can't remember the exact locale off hand, but it often gets clogged with mud and crud.

Your tank strainer may be clogged as well. Try swapping the return and supply lines in the engine bay. This will bypass the tank strainer and tell you if the strainer is clogged. Or you can also use a small can or jar of fresh fuel in the engine bay with the supply and return lines in the container and see if she'll run. If the problem persists with either of these option, then you've got lift pump or injection pump issues.

If you're unsure that you actually had fuel I'd try the fuel in a jar trick from above and see what happens. The fuel level senders on these cars a rather finicky at 30 years old. They are often jump and read incorrectly especially when the level is low.

Also if you post your location, there might be a member here that can stop by and help troubleshoot.

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Fuel tank on a 240D is 17 gallons. and with a 4-spd manual should be getting 28 - 30mpg.

make sure the battery terminals are clean, the ground strap to the body. there is another ground strap from the engine to the body on the left rear. look under the oil filter housing, yuou should see it.

The hissing, could be a plugged fuel tank vent. loosen up the fuel tank cap and see if the engine will run better. a plugged vent will collapse the tank eventually. the vent is under the car behind the L/R wheel. a little bell shaped thing pointing down.

Pull the voltage regulator from the rear of the alternator and see how long the brushes are. or could just have a bad reg. they are replaceable, around $35. held in with 2 screws.

new fuel filter won`t come with new washers. there is a aluminum crush washer that fits under the large bolt and seals to the filter housing. the long bolt will have one rubber "O" ring.

You could be sucking air in some of the rubber fuel lines or the primer pump could be a source of air leak. do you have the style with the white knob or the smaller black one? the white knob old style has to be unscrewed and pumped to prime the system, and the black style, just pump it, nothing to unscrew.

when changing the spin on filter, fill it to the top before replacing it. save on a lot of primer pumping.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

well. as usual you all are geniuses. took off the fuel cap and it started right up pretty much. didn't see that vent off the top of my head but will search out some photos on here and i'll check and see if its clogged. thanks!

Tank size depends on your year. My '79 has a 21 gal capacity, whereas my '83 is 17 gals. Mileage will depend on a number of variables, but the worst you're likely to see is 18 mpg, so you should have plenty in the tank if you drove only sixty miles on a full tank.

I'd try starting with the gas cap off. If you get suddenly start to get fuel, then the tank vent is clearly faulty. (by the way, a bad vent with a good fuel pump can cause the tank to collapse and significantly reduce its capacity). If not, then look to the fuel lines and/or tank screen. Reversing the fuel lines should give you a diagnosis there. I don't think you'd hear suction at the fuel filter inlet if the lift pump were shot, but it's worth checking if the first two tests don't yield an explanation.

Might want to have that alternator checked out before you decide to take another long drive.

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'79 240D

Here is what you're looking for.

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