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-   -   83 240D Injection Pump Not Pumping? (https://mercedesforum.com/forum/diesel-discussions-33/83-240d-injection-pump-not-pumping-54688/)

Buckshot68 05-20-2014 08:50 PM

83 240D Injection Pump Not Pumping?
 
Hi All,
I have never had an injection pump failure in a diesel mercedes, but this may be my first.
My car is turning over good (new starter, battery, starter cable-it's got the power) but it is not starting. I removed the fuel lines to one injector and turned the engine, but only a few drops of fuel came from the line. Then, I tried the other fuel lines and had the same result. Basically, the fuel is not being pumped to the injectors.
Does this sound like the injector is shot. I thought fuel would be gushing from the pump, since it has to be pressure through the injectors?
Any ideas?

Diesel9112 05-20-2014 11:15 PM


Originally Posted by Buckshot68 (Post 166400)
Hi All,
I have never had an injection pump failure in a diesel mercedes, but this may be my first.
My car is turning over good (new starter, battery, starter cable-it's got the power) but it is not starting. I removed the fuel lines to one injector and turned the engine, but only a few drops of fuel came from the line. Then, I tried the other fuel lines and had the same result. Basically, the fuel is not being pumped to the injectors.
Does this sound like the injector is shot. I thought fuel would be gushing from the pump, since it has to be pressure through the injectors?
Any ideas?

If Fuel was gushing out of the Fuel Injection Lines that is the amount of Fuel that would be getting Injected into the Engine and that would be too much.

You need to determine if Fuel is actually being supplied to the Fuel Injection Pump Housing.
The Fuel Filters and or the Fuel Tank Screen could be plugged.

Changing the Fuel Filters and bleeding the Air out of the system takes care of the Filter issue.

If you have more than 1/2 Tank of Fuel you can swap the positions of the Fuel Inet Hose with the Fuel Out let Hose (also known as the Cigar Hose). That will bypass the Fuel Tank screen and draw Fuel from a higher position in the Fuel Tank.

Do one of those at a time and test so that you can tell which one corrected the Problem.

If you are having some massive Air Leak or the Fuel Supply/Lift Pump is not working Fuel is not going to get inside of the Fuel Injection Pump Housing.

You see if you are getting Fuel Volume out of the Fuel Supply/Lift pump by loosening the Fuel out let Tubing (going to be messy) and cranking and seeing if you get anything out of it. Now this is where the Fuel should pulse out.

Remove the Vacuum Hose from the Vacuum Shutoff Valve/Servo and see if it puts out Fuel after that. If it does you are getting Vacuum to the Vacuum Shutoff Valve/Servo when you are not supposed to.

See if any of the above helps you find the problem.

Concerning the Fuel Filters. I have seen new Filters installed on Diesel Vehicles and other Equipment and seen the Filter plug up in as little as 10 minuits. If you got a Tank of Contaminated Diesel Fuel that can happen fast.

Buckshot68 05-21-2014 10:13 AM

I ran a fuel line directly to the pre filter from a gallon tank of diesel, bypassing the tank because I did not know how much fuel was in the tank. I pumped the air out of that fuel line, cracked open the bolt on top of the filter and pumped until there were no air bubbles. Had a friend watch the fuel line while I tried to crank the car. Fuel was being drawn in through the overflow tubes backwards.

Buckshot68 05-21-2014 10:15 AM

Oh, I did remove the vacuum lines to the shut off. I was worrying it might not be functioning correctly and shutting fuel to the injector.

Buckshot68 05-21-2014 12:04 PM

I replaced the hand primer pump with the new style pump because it looked to be leaking. I removed the primer pump assembly to tighten the fuel connections and discovered it looked different than the ones I have seen in the past. It was only connected with two bolts to IP, rather than three bolts. And it had a solid pin that went into the ip, instead of the roller. The inside of the ip looked like it should take a roller, not a pin. Is this a new type of replacement for the roller? I though it odd.

Buckshot68 05-21-2014 01:21 PM

IP Primer Pump Assembly
 
3 Attachment(s)
Here are some pics of my IP, the fitting of the primer pump assemble, and the two different primer pumps. The one that fits my IP is the one on the left. I was confused as to why it has a pushing pin , instead of a roller. It fits inside the IP, but does not seem like it would matchup against the roller inside.

Diesel9112 05-28-2014 07:37 PM

1 Attachment(s)
There is different types of Fuel Injection Pumps that went on the various Models.

Take a good look at the Fuel Injection Pump in the Picture. This is an MW Type Fuel Injection Pump. Compare it to the one you have.
If the one in the Picture does not look like the one that you have You likely have a M Type Fuel Injection Pump.
The MW Fuel Injection Pump uses a different Fuel Supply/Lift Pump that has a Roller and also has holes for 3 Studs.

You need to use the Fuel Supply/Lift Pump that came with your particular Fuel Injection Pump.
Locate the Banjo Bolt that on the Engine Side of the Fuel Injection Pump and take a look at the head of it. Note if there is a Ball Bearing Pressed into the end or a Plug that you can screw out.
If you have the type that yo can screw out remove that Banjo Bolt and insde if is a Valve. Remove the Plug and there should be a Spring and a Ball Bearing that is the Valve. Stretch the Spring to get a free length of 27mm and assemble it and pump on the Hand Primer to get the Air out of it.
The above is the Fuel Pressure Relief/Overflow Valve and it is what holds the Fuel Supply Pump pressure inside of the Fuel Injection Pump Housing.

See if the return Fuel from there is still trying to go back wards.

Diesel9112 05-28-2014 07:51 PM

You might want to read through this thread: 1985 300sd NO POWER will not rev Bad lift pump? need help!

I was finally able to view Your Pictures. You definately have an M Type Fuel Injection Pump and the Fuel Supply/Lift Pump with the Steel Plunger is what it is supposed to use.

Buckshot68 05-29-2014 03:01 PM

Thank you so much, Diesel9112!!! Much appreciated. I will let you know.

Buckshot68 06-12-2014 06:45 PM

HI,
UPDATE:

I installed new fuel lines to rule out an air leak and installed a new primer pump. I put on new filters, primed them. After cracking open each line on the injectors, I use the hand pump and crank the engine to try to get fuel through from the IP to the engine. Fuel does come out in drops to cylinder one, but not the other cylinders. Fuel is feeding backwards to the overflow lines to the injectors. I am using a line directly from a canister of diesel, not the tank. I have the overflow going back into this canister. Fuel must be making it through the IP housing, but it is not getting to the injectors.
Is there anything I am missing here???
Please help.


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