Hi All,

I’m working on a 190DC with a 220D motor in it. I had to pull the head to fix a bad pre-chamber and a broken timing chain. The car has sat for years, probably due to the broken chain, and I am trying to get it running again.

The problem is I can’t get any fuel to the injector lines. After installing the new chain I pulled the pump with the crank timing mark at 24 degrees and lined up the marks on the pump and re-installed in the same position the pump was originally in. I installed a new primary fuel filter, and then used the hand pump to prime the system using the bleeder screw on top of the filter housing; I also bled fuel out of the bleeder screw on top of the injection pump. With everything closed up I can hear the rasping noise when I use the hand pump which is the fuel going into the return line. I also took the return line off and cranked the motor and the lift pump appears to be working as fuel was pumped out. I also topped the oil level off in the injection pump (up to the fill plug on the side).

The start stop cable appears to be adjusted correctly. I’ve been searching for answers and found something about a stuck rack, but it was on a newer style injection pump, how would I check the rack on the 220 pump? I can look down the oil fill hole and see the start/stop arm move away from the diaphragm actuating rod (sorry don’t know the technical terms) and the rod only moves and 1/8th of an inch or so to the front of the car while the arm moves quite a bit further forward, is that normal? Or could the diaphragm be stuck somehow?

Not a drop of fuel has come out of any of the injector lines. I have all four loose at the injectors and have cranked a fair bit with the starter. Oil pressure comes up fine when cranking. I tried putting vacuum on the governor line from the intake which should actually cut the fuel off as far as I understand it, but it had no effect. It didn’t hold vacuum either though so would that mean it needs a new diaphragm? Could that be causing lack of fuel? I would think it would just keep the governor from working at higher speeds.

One other stupid question, as long as the pump is turning it should pump fuel out of the injector lines regardless of timing right?

Any help or things to check would be greatly appreciated. Thanks.

Sven

Last night I tried a procedure in the FSM where you pull the cover off the rod at the mounting end of the IP and then push the stop/start lever to "hard" stop, then put your finger over the vacuum fitting for the governor at the other end of the IP and release the lever and watch the rod. The rod is supposed to slide or move a "little" and if it keeps moving it means the diaphragm is bad.

I'm not sure what they mean by a "little", but my rod only moved a barely perceptible amount, no way I could even measure it. I then took a hose attached to the vacuum fitting and blew and sucked to see how much it would move and it would only move the same amount. I'm not sure what that means, if that rod is stuck or if that's normal, but I think I'm going to pull the pump out this morning and pull the diaphragm housing off and see what's going on.

You might want to have the admins move your thread to the Vintage forum. In addition, I have a 200D engine and transmission for sale that I might end up parting out if the injection pump would help you.

Did you change the oil in the injection pump or just top it up? Sounds like you are on the right track though......just keep at it.

Good Luck

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Thanks Daw_two, I'll try and get this one working, but if not I'll let you know about the pump. I did just top off the oil, but when I pull the pump today I will drain it, clean it out and re-fill with fresh.

Junkscouts-
I have the same engine as you and some of the same challenges, so unfortunately I don't have any great words of wisdom. Except, there is a forum member here named Govert (and he is on benzworld.org as well) and he is really helpful and knowledgeable about the diaphragm governed injection pumps. You might look him up and PM him directly.

Based on your description, it sounds to me like your diaphragm is okay. What Govert has discussed previously is additional leakage that occurs around something called the poppet cam. It is the rotating part at the back of the IP, not far from the outlet that you were covering with your finger. I guess the bearings and seals leak which affects idle control. I do not think this sort of leak would keep fuel from getting to the injectors, but they would keep your vehicle from idling well.

So my hunch is that it is something bigger than a leaking diaphragm or poppet cam, but I don't have any other suggestions. Good luck.

Thanks Shortsguy1. I did partially pull apart the pump and the diaphragm does look ok although it is made of some kind of cloth instead of the brittle old rubber I was expecting. It doesn't seem like that cloth would hold much of a vacuum though.

So I pulled the pump out of the car and then ran gasoline through it with the hand pump and then cranked the pump with the gas in there. In the process the injector line outlet closest to the oil fill started squirting but the other three are still dry. I then proceed to pull all the cover plates off as well as the diaphragm housing.

I think the pump is just gummed up after sitting for 10 plus years. Two things seem wrong to me. First the rack visible behind the access plate on the side of the pump only moves a little but I think it should move quite a bit further back. In this picture you can see the rod which I believe is the rack with a bracket and screw at each of the pump's cylinders and then to the right on the rod there is a clip who's only purpose appears to be to keep the rod from going too far to the right, this is why I think it should move much further to the right than it does. Anyone know how much it should move?



Here is a video of how much the rod moves:
Mercedes 220D Injection Pump :: MOV03230.mp4 video by junkscouts - Photobucket

Also in the picture above if you look at the springs behind the rack you can see two of the lifters (for lack of a better word, these things ride on the cam like lobes on the main shaft below) at the base of the springs on the one on the left and the 3rd from the left. These two stay up all the time while the other two which you can't see in the picture move up and down as you rotate the main shaft. The two that stay up can be slid down with a screw driver but on the next rotation of the crank they stay up again. They may free up if I keep pushing them down, rotate and repeat. I'm unfortunately out of carb cleaner but I've rinsed everything with gasoline including the "crank case" and then sprayed PB blaster on everything.

Anyone have any tips for freeing up these parts? Any problem with submersing the whole thing in gasoline for a while? I could use acetone, but I'd be worried about it eating some of the rubber seals if there are any left. I haven't searched for any yet but are there any rebuild kits available for these pumps?

There are more pictures here of the pump for anyone interested or if you are going to take one apart they might help you: Mercedes 220D Injection Pump pictures by junkscouts - Photobucket

Thanks for the help guys.

Sven

Well that is the Rack right in the front of the Picture; with the steel Blocks with Screws. Move it by Hand and see if it is sticking.
Don't thouch the Screws on the Blocks that is how the set the Fuel adjustment for each of the Elements.
There is a few people who have had stuck or gummed up Fuel Injection Pumps.

__________________
84 300D, 82 Volvo 244Gl Diesel

Diesel911,

It does move, but barely. Do you know how far to the right it should slide? From looking at it it seems like it should move maybe a half inch or so but it's only moving maybe 1/16th or 1/32nd of an inch or less. I tried prying lightly with a screw driver on the bracket on the diaphragm end of the rod but it didn't give at all so I didn't push it.

Sven

I think you need to get some carb cleaner or something similar and get those 'lifters' ungummed. Sorry, no idea on how far the rack should move, although my intituion is that it should be much more than 1/16th.

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Hoping for an update on this issue.

.

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The injection pump elements stuck from long sitting would be common as well. I would start with getting some solvent in there and tapping the ones stuck or immobile at the top of their bores and pushing them down to meet the cam in its lowest position . Doing this several times may loosen them up. Some form of penetrating oil might be best and let them sit awhile after moving any stuck elements to give the solvent portion of the penetrating oil a little time to work.

I know this is an older thread but anyone reading it with similar issues might benefit.

I have the same problem with the injector pump on my 72 220D. Could it be just gummed-up and need a cleaning? Its been over 20 years since the engine ran. I do not have any fuel coming out of the injector lines when I crank the engine.

The 2 that are stuck up are stuck up their due to rust and or dried Fuel and are also likely to be what is keeping the Rack from Moving. If the Element Plungers that are stuck up do not come down they cannot fill up with Fuel.
On the others it is also possible that the Fuel Feed Holes in the Elemens are plugged.

I can tell you what I have done in the Past to loosen up stuck Plungers but I cannot guarentee it will work.

First of all do only one at a time. Next before removing the Delivery Valve Holder all of the Fuel Lines must be removed and you lay something flat a crossed all of the tops of the Delivery Valve Holders and note that they are all the same Height.

Remove one Delivery Valve Holder, Remove the Spring inside and remove the central Valve and look down into the Hole. You should be able to see the top of the Element Plunger. Squirt in some Penatrating Oil and let that soak if you want.

A this point you will need a 1/8"-3/16" depending on the size of the Hole Brass Rod about 3-4 inches long.

round the tip of the Rod that is going on top of the Element Plunger and find something that is light weight to tap on the end of the Rod that is sticking out.

But, here is the tricky part. If the Camshaft Lobe in the Fuel Injection Pump is up when you tap the Plunger is not going to Move. So you have to rotate the Pump a bit tap tap and see if the Plunger Moves. You keep doing that till you feel the Plunger move down. The Plunger should not move more than 1/4" or so.

A other trickie part. You do not want the outer Barrel of the Element to rise up as it can come out of the Slot that lines it up. So when you turn the Fuel Injection pump watch in side and see if anything besides the centeral Plunger is moving.

When the Plunger is loose spray in some more Oil and assemble it. At this point you don't need a New Crush Washer but you need to assemble it completely and snug down the delivery Valve Holder so the Element Barrel will not move.
Then go to the next one.
Run the Delivery Valve Holder down snug but do not torque them. Lay that flat thing you used before over the top of the Delivery Valve and see if any are sticking above the others.
If one or more are sticking above the others there is a chance that the Element Barrel came out of the Slot and did not go back. If you torque the Delivery Valvel Holder like that you can ruin something.

Go to this site and see if you can find a picture of the Fuel Injection Parts so you can see what you are dealing with.'
Pick a site:
http://mb.ilcats.ru/

http://www.mbpartsworld.com/

__________________
84 300D, 82 Volvo 244Gl Diesel

I removed the delivery valve holder, spring and central valve. The central valve looks like the attached image. Is the central valve two pieces? Below that is a solid piece with a hole in the center. Image attached. I tried tapping on that valve as you suggested but it does not move. I cranked the engine over and it still does not move or it I tap it there is not movement. I checked the other three and none of them move up or down. Am I doing this correct?

Attached Thumbnails

   

Don't know how to attach images to thread..