'79 240D won't start

Hi all, All I did was put on new fuel filters, both primary and secondary. It cranks and occasional tries to fire but just can't. What the heck happened? Any ideas? Was running fine before that. Thanks, Steve

Reply to
runbiodiesel
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Air in the system?

Did you bleed all the air out when you changed the main screw-on filter?

Reply to
Karl

That's all I could think of too. I've changed those same filters on my old 240 and both my 300 diesels with no problem and I did it the same way.

If it is air > Air in the system?

Reply to
runbiodiesel

On top of the main filter is 2 banjo bolts. One has arrow pointing to the filter. The other has an arrow pointing away. The line goes down to the front of the injection pump. Take a 17mm wrench and crack open the banjo bolt with the arrow pointing away. Operate the hand pump until straight fuel pumps out. Close the fitting. Start the car. Any other air will just be in the injectors and bleed out quickly.

Earlier diesels had a bleed screw on top of the injection pump between the last two foot valves so you can bleed the pump all the way to the foot valves. But the last I have seen this on was the 115 bodies [76 and back].

If it is air > Air in the system?

Reply to
Karl

OK, I did that when I installed the filter, but apparently not long enough. I just did it again and there WAS air in the system. So I pumped until I had a lot of straight fuel coming out, tightened it back up and cranked and cranked and cranked. Nothing. Not even a sputter now. Any next steps?

Reply to
runbiodiesel

There's air in the high pressure lines and nozzles. Floor the accelerator and keep it floored while you crank the motor to expel the air.

Reply to
-->> T.G. Lambach

On Jan 21, 1:41=A0pm, "-->> T.G. Lambach

Reply to
runbiodiesel

. Assuming the air is in the high pressure lines and nozzles, how

It's been a few years since I last did it, but from memory it's easier as a two-person job. One person cranks the engine from the driver's seat, the other opens the 17mm hex cap-nut that connects the high- pressure line to each injector, in turn. Barely open each nut until diesel appears, then squeeze them up again. On your own, I suppose you could open them all, crank, and check for a showing of diesel at each.

I once had an experience with an audi diesel that wouldn't restart. It turned out that the front of it was lifted while the fuel line was open, and the diesel all flowed back to the tank. It took an age to re- start it, we had to slightly pressurise the tank with an air line to get the diesel up to the engine. Just thought I'd mention it in case your car was not on a reasonably level surface.

john

Reply to
John (Ireland)

Well, lesson learned. It took a LONG time to get the air through. I guess since I'd never had a problem before I rushed the bleeding process. Never again! After one more battery run down, it started. Noticeably peppier too with the new filters! "Peppy" being very relative in a 240D! :)

Reply to
runbiodiesel

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