Hello,

This is my first time rebuilding the engine of a 1975 Mercedes 240D diesel. Changed O-ring on fuel injector, cleaned up fuel pump, and all reassembled but the engine won't start. Primed the fuel line many times - no fuel came from the line to the fuel injector. Any advice would be appreciated.

Thank you,
Wayne

Maybe God's telling you to get a 617 turbo diesel and give up in the go kart!

Lol sorry just kidding.

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When you're priming, are you getting fuel from the return line?

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1981 240D 4sp manual. Ivory White.

On Mutt the Race Truck (Chevy S-10 with an OM617) I've used every priming trick I can think of as well as the online tricks, all to no avail. The purists scream and pull out their hair but whenever I have to open the fuel system I always have to start Mutt with starting fluid for a few seconds. Once he's running everything is fine from then on. I know this isn't the approved method but it DOES work. So far no damage and I run this engine much harder than you folks will ever run yours - full rack for a mile at a time, shifting at 5200 RPM (4 speed manual) with engine mods good for about 230HP. I'm not recommending this method, just saying that it works.


Dan

Oh, I get it.

Whenever I need to open my pump (timing purposes), I have an awful time getting all of the air out. Removing hardlines, not so much. Draining the pump (OFV), not so much. But both? Woof...

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1981 240D 4sp manual. Ivory White.

I really hate to use starting fluid, but sometimes we have to. I like to disconnect the glow plug relay, or just let the glow plug cycle end, and let them cool for a minute. I want the compression to ignite the ether late in the compression stroke, not let the glow plug ignite it early.

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'75 John Deere 450C (times 2)
'83 240D plus parts car
'87 F350, 6.9L IDI
'89 F350 crewcab, 7.3L IDI
'89 F-Superduty, 7.3L IDI
'91 F-250, 7.3L IDI
'91 F-350, 7.3L IDI
'94 F-350 Crewcab, 7.3L IDI
'94 E-350 Ambulance, 7.3L IDI

I think we all have this problem one time or another.....

I can usually get the engine to begin running on two or three cylinders, I learned the hard way to never, EVER let off the full to the floor throttle until all cylinders are hitting .

Yes, it souds like you're going to kill it but the governor will prevent that from occurring .

Many loosen the injector hard lines at the injector end one 180 degree turn , pin the throttle and then crank until the bubbles stop, stop cranking, tighten the loose hard line ends then start it with the throttle pinned, it'll still not start on all cylinders but seems to fire up *much* faster and certainly is easier on the battery and starter...

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

If the Fuel Injection Pump was removed from the Engine and you are getting good amount of fuel when you loosen the Fuel Injection Hard lines at the Injector the suspicion would be the Fuel Injection Pump is not timed correctly or some other timing issue.

The presumption on the above is good compression.

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84 300D, 82 Volvo 244Gl Diesel

The starting fluid issue as mentioned is having the glow plugs on when you do it. The other is spaying in what may be more then you need into the intake and then running to crank and start the engine. That is a good way to get a larger gulp of starter fluid then you need into the Engine.

Instead disconnect the Glow Plugs at that wire coming off the fire wall or at fire wall the one at the very rear that connects the Glow Plugs to the voltage and have someone else start cranking the Engine while you control the starter fluid spray. That way you spray in the minimum needed to start.

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84 300D, 82 Volvo 244Gl Diesel

I am getting fuel from the return line without any bubbles. Started the engine and tried loosening the injector hard lines for all four to no avail. Started the engine again, but still no fuel came out from the fuel injector pump to the injector. I'm unsure what to try next.

Thanks,
Wayne

Are you parked on a hill by any chance?

Can't remember when or where I read this, but the fuel rack fills from the first element (toward the front of the car).
If you're nose up -which I've been every time this has occurred- it's possible to get a big air bubble in there that won't bleed out until the engine is running. The OFV is in the middle of the pump.
The primer simply can't generate enough pressure to compress the air sufficiently. Once the lift pump is going it's another story.

Crank for whatever amount of time is safe, let the starter cool for whatever time is recommended, and repeat.
That's all I've been able to do in the past when the IP was sufficiently air bound to prevent ignition.

Mind you, some of the purists here will keep directing you toward the hardlines... food for thought.

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1981 240D 4sp manual. Ivory White.

Hello,

My car is parked on level ground. When I rebuilt my car I took off the fuel injector pump for a year and replaced the flat copper washer seal and O-ring for the injector. Do you think its possible that the fuel injector pump could be damaged as a result?

Also, I set the timing on the engine 24 degrees and I aligned the fuel injector pump to the slot but it keeps clicking past the slot about 5 degrees. Could that have messed up the timing?

Thanks for your response,
Wayne

I think you really just gotta get it running with the fluid.

All of us have had this problem where it seems like it's never gonna start, u go through a week of trickle charging the battery every night and are so worried your gonna ruin your starter. Your wife it's annoyed with you for making her come turn the key for an hour everyday lol. But then almost magically it finally kicks on.

I'd really try to the starter fluid method with a buddy with throttle slammed.

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So it is easier to for others to understand the Mercedes Service Manual due to who translated it from German often uses several names for the same part in different parts of the Manual and the Parts Manual or references may ever have another name.

Here on the Forum the Injector is the part of your fuel injection system that screws into the Cylinder Head.

In the attaché picture is the name of some of the parts. These names were what was used when I worked in a fuel injection shop.
In the Mercedes Factory Service Manual part called the Delivery Valve Holder is called "Pipes" or "Pipe" in some parts of he Manual and I think apparently called Injector in some other parts of the manual or parts catalog.

Where the crush washer is in the pick does not indicate the order/position that the Crush Washer was supped to go in.

Also the picture is for an M Type Fuel Injection Pump not the MW type that comes on my 84 300D.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel