Reset MEP-002a won't stay running more than a minute

[JOHNPFD1]

I have an MEP-002a that was reset and had 2.8hrs on it. I have tried to get it started numerous times, it will run the first time for about 2 to 3 minutes then gradually starts to die.
If I run it after the initial 1st time it will not run for more than 1 min almost exactly 1 minute.
I have checked the fuel system I get plenty of fuel and have tried manually holding the fuel solenoid open and it will still die.
I have jumped out the oil pressure switch and replaced the temp switch and still does the exact same thing.
There is slight white smoke when I get it running but that usually goes away.
Any ideas would be greatly appreciated.

 

[jamawieb]

It could be the plunger guide in the injector pump, it may be able to start, then falls out of place, making the unit stop.

Also, check the timing of the injector pump. For some reason the last 2 units that I've got from the military have had the wrong timing buttons. If the pump is replaced, then they have to make sure it doesn't need a different timing button. I can help you check the correct timing button is installed, just let me know.

 

[R Racing]

There is a check valve inline from the fuel pump to the injector pump. check it for being sticky or trash in it.

 

[Keith_J]

There is a check valve inline from the fuel pump to the injector pump. check it for being sticky or trash in it.

Bingo. Trashy fuel causes them to leak causing slow pressure drop which reduces fuel flow. At 1800 rpm, there isn't enough time to fill the plunger with low priming pressure.

also check fuel pump strainers, they clog easily and are a prime bad fuel bottleneck. If you tank looks like a Mississippi River sediment, your strainers are clogging. Clean diesel makes any engine happy.

 

[JOHNPFD1]

Jamawieb, I would welcome any help you can give me

 

[JOHNPFD1]

R Racing, I did check the valve and it seems to be working and clean with no issues

 

[JOHNPFD1]

Keith J I have fresh fuel and the tank is brand new. I am using an external pump from another unit and not using the ones on the unit because there may or may not be an issue with them working properly.

What drives me crazy is how it runs the first time the longest and after that it will not run more than 1 minute.

 

[Isaac-1]

Are you getting good fuel return to the tank, back pressure on return lines can cause some types of injection pumps to stop pumping, not sure about the Ambac M-50 on these though.

 

[JOHNPFD1]

Isaac-1, Yes I get good fuel return to the tank, it is not a solid stream but it is a steady flow, is it supposed to be solid or a weak stream back to the tank?

 

[Ddmk18]

My injector timing was off 180* and it would just for a few minutes then slowly die off. Restart run for a minute or two then die off again. Does your valve cover get really hot in the couple minutes it runs?

 

[jamawieb]

Jamawieb, I would welcome any help you can give me

Reference pictures on TM-34 page 137 if your unsure of the parts of the IP
1st: You need to remove the cap nut and delivery valve holder, then remove the valve spring. After you remove the spring, put the cap nut and delivery valve back on.
2nd: Remove the injector line off number 1 cylinder.
3rd: Set your timing mark to PC on the fly wheel. Then rotate the motor counter clockwise 15 degrees.
4th: Turn on the fuel pumps and you should have fuel coming out of the number 1 outlet on the ip (It shoots out about 2 feet so make sure you have something to catch it); rotate the motor clockwise until the fuel stops coming out of the number 1 port. Turn off the pump.
5th: When the fuel stops look at the timing marks on the flywheel, if it has the correct timing button your timing mark will be on PC. If it's not on the PC mark, the wrong timing button is installed or the pump timing is off due to someone installing it incorrectly.

Let me know the results and I can help you figure out what button you need.

 

[JOHNPFD1]

Ddmk18 yes the valve cover gets very hot after running it a few times
How do you check and adjust the timing of the injector?

 

[jamawieb]

Ddmk18 yes the valve cover gets very hot after running it a few times
How do you check and adjust the timing of the injector?

Your IP timing is off by 180 degrees.

 

[jamawieb]

1st look at the TM.
What you need to do is take off the valve cover closet to the blower. Turn the blower until you see the intake valve open and close on the cylinder closet to the blower (this will be the start of the compression stroke of number 1 cylinder), keep turning the blower and watch the flywheel marks until you see the PC mark lined up with the indictor. After that there is a small flat head screw on the IP, towards the back, on the left side, toward the block. You need to take the screw out, then put a small drill bit into the hole until it bottoms out, then CAREFULLY turn the blower left and right, you should feel the drill bit move and get tight (there is a slot on the ip that the drill bit will fall into). If you don't feel the drill bit get tight, then it's not in the grove and would mean that it's off. If it is off, set the PC mark on the flywheel back to where it is lined up with the indictor. Then take the IP off, after removing turn the head on the IP until you can put the drill bit into the hole and have it slide into the grove. Finally just put the Ip back on and it should be ready.

 

[Ddmk18]

Well he is mostly right. If it doesn't fall in the slot when you line up the The PC marks Turn it another 360° and see if it falls into the slot on the PC Mark again that would mean that your 180° out of time. Remember the camshaft turns at half the speed of the crankshaft so that's why you turn it another 360° to see if it lines up

 

[Ddmk18]

Then to turn it 180° Loosen the pump back it off the gears turning the engine 360° till the PC Mark comes up again and install your pump and try it at that point

 

[JOHNPFD1]

Thanks for all the help. It sounds like it is an issue with the pump timing, I will be working on it this week and let everyone know how I make out. Thanks for all the help so far, you guys are the best.

 

[Ray70]

Hi John, your machine is a Letterkenny reset, so who knows what they may have assembled incorrectly! If you have trouble checking the IP I can help you if I see you Thursday night, but Ddmk18 and jamawieb seem to have it covered.