MEP-004a injection pump problems

[Tatersalad812]

soooo... i bought my 4th and 5th generators this week. both are mep004a and I started going through one to get it running after fighting with everything under the sun i finally got fuel to the injection pump... i found the solenoid on top of the pump to be stuck in the running position.... not sure how thats possible but hey i always get the weird stuff. The rack in the pump was also stuck in the run position so i moved it a couple times and it freed up. i still for the life of me cant get the injectors to get fuel. i cracked the lines at the pump and i get notta. what am i missing? should i pull the pump and rip it apart and clean everything? it doesnt look as simple as my mep002a pump. any tips or tricks gettting deep into the pump? oh and the glass ball is clean as well as the filter on the pump inlet. iv got fuel in and out of the pump but nothing at the injectors. ive got the throttle at half. thanks in advance for any and all help

 

[Scoobyshep]

I had a 005 act the same way. Ended up the shaft in the pump had sheared

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[Scoobyshep]

Theres an access plate on the side of the pump. You can remove that and see if the pump is turning over. Fuel goes here so be ready for that

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[Guyfang]

This gen set is well known for taking a long time to bleed itself. Crack the lines at the IP and see if anything comes out. If you get fuel out of the lines, tighten them up and crack the injector line farthest from the IP and turn it over. Your sure the L1 solenoid on the IP is getting voltage and working?

 

[Ray70]

I had a similar problem with an 005 recently. Rebuilt the pump and then got nothing out of it.
I believe the problem was just as Guy stated. The gravity feed system took FOREVER to get the air out of the pump cavity so that the transfer pump in the end of the IP could start working.
I ended up loosening the screws on the top cover and letting it sit ( with the day tank full ) overnight and that eventually seemed to help bleed out the air. I think the trick is to create an opening where the air can escape so that fuel can gravity feed into the cavity.
The 002 /003 is a different system which is under pump pressure, so it will force the air through and out the return line.
Your system is not under pressure and the glass check ball is blocking the air from escaping easily.

 

[Tatersalad812]

Theres an access plate on the side of the pump. You can remove that and see if the pump is turning over. Fuel goes here so be ready for that

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I opened the back of the pump and the pump is spinning and the veins aren't locked up.. any other ideas?

 

[Tatersalad812]

I had a similar problem with an 005 recently. Rebuilt the pump and then got nothing out of it.
I believe the problem was just as Guy stated. The gravity feed system took FOREVER to get the air out of the pump cavity so that the transfer pump in the end of the IP could start working.
I ended up loosening the screws on the top cover and letting it sit ( with the day tank full ) overnight and that eventually seemed to help bleed out the air. I think the trick is to create an opening where the air can escape so that fuel can gravity feed into the cavity.
The 002 /003 is a different system which is under pump pressure, so it will force the air through and out the return line.
Your system is not under pressure and the glass check ball is blocking the air from escaping easily.

Ok so more updates and info, I pulled the side cover and there are 2 surfaces visible. A left and a right. The left has a line on it and doesn't spin the right side spins.. has crud all over it but spins while cranking. The solenoid on top was frozen but it was frozen in the run position. Ive got it freed up and working pump is full of diesel Ive even tried to start it with the top cover off and still no dice. Not a single drop out of the injection lines. They are wet but don't drip. Im betting something is gummed up but not sure where to start to take the pump apart. I even went as far as to run it on starting fluid.. i never use it on a diesel but frankly I was mad and tired of fighting with it so I ran it slowly on starting fluid with the lines cracked and the battle short on so the fuel pumps would run and still didnt get any out of the lines

 

[Scoobyshep]

Ok so more updates and info, I pulled the side cover and there are 2 surfaces visible. A left and a right. The left has a line on it and doesn't spin the right side spins.. has crud all over it but spins while cranking. The solenoid on top was frozen but it was frozen in the run position. Ive got it freed up and working pump is full of diesel Ive even tried to start it with the top cover off and still no dice. Not a single drop out of the injection lines. They are wet but don't drip. Im betting something is gummed up but not sure where to start to take the pump apart. I even went as far as to run it on starting fluid.. i never use it on a diesel but frankly I was mad and tired of fighting with it so I ran it slowly on starting fluid with the lines cracked and the battle short on so the fuel pumps would run and still didnt get any out of the lines

thats the timing mark for the pump, if its spinning then your shaft is good. If you are still not seeing any fuel coming out of the output lines then the pump may be internally gummed up. If it were me id seek a diesel engine shop to rebuild the pump.

 

[Tatersalad812]

thats the timing mark for the pump, if its spinning then your shaft is good. If you are still not seeing any fuel coming out of the output lines then the pump may be internally gummed up. If it were me id seek a diesel engine shop to rebuild the pump.

do you or anyone have a link to a service manual? im confident in rebuilding it myself. ive done much more for way less i just need destructions lol i also have 2 of these to do both are probably sludged and im layed off ive got more time than money right now

 

[Scoobyshep]

do you or anyone have a link to a service manual? im confident in rebuilding it myself. ive done much more for way less i just need destructions lol i also have 2 of these to do both are probably sludged and im layed off ive got more time than money right now

click the TM tab on the header of this site, search for generator and electrical, look for mep004.

 

[Guyfang]

The 004A and 005A are for the most part the same-same. If the 004A TM, and you want the -34 TM, if its hard to read, then simply open the 005A -34 TM and its should be better quality. Ray 70 has done this at least once, and is a world of knowhow.

 

[Tatersalad812]

The 004A and 005A are for the most part the same-same. If the 004A TM, and you want the -34 TM, if its hard to read, then simply open the 005A -34 TM and its should be better quality. Ray 70 has done this at least once, and is a world of knowhow.

Thanks for the info, dug into the pump... it came apart super easy. Found a ton of dirt and the bottom 2 pistons are rusty and 1 of them is stuck. So I'd say I found the probem. Ill update as I have more info

 

[Ray70]

Well.... I'm not sure you found your problem just yet. The power piston being gummed up won't cause your issue, but is a sign of other issues. Take out the rotor assembly and check if the 2 side plungers are stuck. These plungers are what does the pumping action at high pressure. If they are stuck in the head they will not pump anything.
Next, if you have little speck of black plastic crap in there, your flex coupler ring is falling apart. There is a new updated weight basket available that eliminates this plastic / rubber disc.
When you reassemble pay close attention to the instructions! If you go by any videos on the internet BEWARE! There are 2 versions of this pump, Clockwise and Counter Clockwise, depending on which side of the motor the pump is mounted. Follow the TM instructions, everything on the internet is based on stuff like John Deere etc. which is mounted on the opposite side and turns the opposite direction.
Lastly... and Guy will vouch for this... LUBE the crap out of the umbrella seals on the input shaft. If the one closest to the pump flips over you will leak diesel into your oil pan!
After you install and time it ( per the TM directions ) Do as I stated earlier to bleed, or better yet, dump clean diesel into the upper cavity until full to help Pre-fill it.

 

[Tatersalad812]

Well.... I'm not sure you found your problem just yet. The power piston being gummed up won't cause your issue, but is a sign of other issues. Take out the rotor assembly and check if the 2 side plungers are stuck. These plungers are what does the pumping action at high pressure. If they are stuck in the head they will not pump anything.
Next, if you have little speck of black plastic crap in there, your flex coupler ring is falling apart. There is a new updated weight basket available that eliminates this plastic / rubber disc.
When you reassemble pay close attention to the instructions! If you go by any videos on the internet BEWARE! There are 2 versions of this pump, Clockwise and Counter Clockwise, depending on which side of the motor the pump is mounted. Follow the TM instructions, everything on the internet is based on stuff like John Deere etc. which is mounted on the opposite side and turns the opposite direction.
Lastly... and Guy will vouch for this... LUBE the crap out of the umbrella seals on the input shaft. If the one closest to the pump flips over you will leak diesel into your oil pan!
After you install and time it ( per the TM directions ) Do as I stated earlier to bleed, or better yet, dump clean diesel into the upper cavity until full to help Pre-fill it.

Yea the whole inside of the pump is the problem its filthy lol, all of that is noted. Im going over it with a fine tooth comb to get everything clean and flowing. Im down what I belive to be the advance stud, the ones the power pistons push on.. is their a special tool to get it out kinda looks like a torx but doesn't at the same time. And thanks for the tips ill make sure I follow the tm to the T

 

[Ray70]

You are correct, it's very similar to Torx but does have a different name ( which eludes me at the moment ) , however a Torx bit does work, think it's a T-40 or a T-45.
They are extremely tight, so be careful the ring doesn't try to rotate while you're loosening the ball stud.

 

[Tatersalad812]

You are correct, it's very similar to Torx but does have a different name ( which eludes me at the moment ) , however a Torx bit does work, think it's a T-40 or a T-45.
They are extremely tight, so be careful the ring doesn't try to rotate while you're loosening the ball stud.

you know sir... your freaking awesome! another question for ya... fuel filters.. i have 2 large cans and 1 small. ive got the 6 and 10 micron for the big cans but i cant find anyone referencing what goes in the little guy i would imagin its a water seperator.

 

[Scoobyshep]

Little guy is a water seperator. He can be cleaned

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[Tatersalad812]

Little guy is a water seperator. He can be cleaned

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is there supposed to be an element in the housing? i bought mine without anything in them

 

[Scoobyshep]

is there supposed to be an element in the housing? i bought mine without anything in them

Yes, It looks like a bunch of stacked up plates

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[Tatersalad812]

Yes, It looks like a bunch of stacked up plates

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Well the high pressure plungers are stuck in the shaft and tips or tricks on how to get them freed up? I've tried heat and freeze spray and oil and can't get them to budge