MEP- 002a losing 24v power at start-up?? POWER ISSUE SOLVED!

[jamawieb]

Couple of things... Don't trust the onboard Panel Hz meter. The sender or gauge itself can go bad. I would use a Kill-A-Watt meter, or the like, to verify all Hz & Voltage readings.

As you indicated the Control Box has been replaced & the Mfg Placard is probably associated with the Genset it was taken off of. So, the date stamped on it would be meaningless. From the looks of it I would say your unit is in the range of the early to mid 80's.

I must confess I have limited mechanical knowledge with the "Injection Pump & injectors". I am fortunate that all my gensets start reliably & run within parameters so far... knock on wood! Although I've familiarized myself with the IJ pump & injectors inner workings from several excellent SS threads where they dive deep into the IJ pump rebuilds, etc. and would not fear "hands on troubleshooting" them on my gensets.

Thus, I cannot determine if your present generator's sporadic engine issues are caused by the injectors, IJ pump or....? Perhaps someone @Ray70 or @jamawieb can better direct you towards troubleshooting tips to pinpoint the engine bogging down & RPM issues you are experiencing.

It sounds like the plunger guide may be cracked or striped and letting the guide get out 180 degrees. Ive had a couple that would run good, then on another startup run like crap and make the head super hot like yours. Temperatures would be almosy 400 degrees with no load. Sometimes the guide will strip and not hold the plunger in the right position throwing the injector timing off.
Ray70 does an excellent job in rebuilding the injectors but i would time the pump first before moving forward. Then if its off time pull and check the guide.

 

[jamawieb]

There is an ambac injector pump manual on the sight that shows the way to check timing. Basically you take the valve cover off number 1 cylinder. Then rotate the motor until you see the intake valve open then close, then look in the sight hole for the flywheel until you see PC; turn until your about 3-4 marks before PC. Take the IP nut off the front and remove the delivery valve spring. Then take number 1 hard fuel line off to see fluid spray out. Turn the fuel pumps on, you should have fuel spraying out number 1 hard line, turn the motor over by hand until you hit PC on the timing mark. Fuel should stop flowing. If it doesnt then the pump is off

 

[Cm131]

Jamawieb thanks for the info.
chainbreaker thank you as well. and for the tips.

so I am thinking I should at least check the timing and then see where I’m at. Valve adjustment was already gonna be on my to do list so might as well do it now. If the timings good then proceed to the next route. If timing is off then correct it and see if it holds.
How do I find the manual here? I am going to start looking for it now. But I’m brand new and haven’t figured out how to navigate confidently yet.

 

[Chainbreaker]

How do I find the manual here? I am going to start looking for it now. But I’m brand new and haven’t figured out how to navigate confidently yet.

The TM's can be found at the top of the page in the banner up top. You will need to select the "TM" & then wade though all the pgs of TM to find those associated with the MEP-002a unit. However, I will save you the time and provide a direct link to: MEP-002a TM's. THey will show up and there may be a notice saying: "You have insufficient privileges to post here" ... just ignore & select them up top of pg. You can then save them to your device and/or view directly.

 

[Ray70]

Also today it seemed the head was getting pretty hot as it would smoke a little after shutting off. Didn’t do that before or when running correctly.Louvers opened 1/4 -1/2” no load.

This is probably the key indicator to your issue! And @jamawieb has already picked up on it...
If your valve cover is getting abnormally hot within like 5 -10 minutes of running with no load, my bet is that your plunger guide in your IP has skipped 90* and your pump timing is now way off.



The plunger had a flat on one side and an opposing curved side. If the pump sits ( especially with the crap fuel these days ) and the plunger gets gummed up, the plunger guide is designed to split in half to prevent further damage.
I've seen a dozen cases in the last few years where rather than splitting in half, the GU8546 plunger guide skips 90* then the plunger breaks free of its varnish and begins rotating, allowing the engine to run, but with the timing that far off it is typically a little slow to start, low on power and the head gets hot very fast!

 

[Cm131]

Chainbreaker thanks for the link. I have all the manuals out of that section now.

 

[Cm131]

Ray70
Thanks I definitely want to check the timing. I’m currently trying to find the step by step procedure. I’m working on the unit today but at this point I don’t want to start it anymore until I have checked the timing.

 

[Chainbreaker]

Ray70
Thanks I definitely want to check the timing. I’m currently trying to find the step by step procedure. I’m working on the unit today but at this point I don’t want to start it anymore until I have checked the timing.

If you haven't already you should review this pump rebuild thread. It covers everything from A-Z with great pictures to get familiar with how the pump works & is timed. Also, the MEP-003a's pump is same as -002a's.

 

[Cm131]

Thank you. Just found it in the manuals. Goi
G to do the flow test first.

 

[Ray70]

Yes, Don't run it too long in that condition. You will overheat the injectors and they will eventually start to stick if you get them too hot.

 

[Cm131]

That’s what I’m afraid of. Is cylinder 1 by the air filter or the end of the machine by oil cooler.

 

[Cm131]

What should I soak my injectors in to clean them?
Do they need to be torn down further than the photos for soaking??
This is what they look like after 5-8min run yesterday. They were cleaned prior and looked way better than this.
I will update later as what I did today as far as flow test but to my limited knowledge I think I’m still in time.

 

[Ray70]

If the pintles pulled out easily you are 99% there already.
Just clean off the tips of the pintles and get down inside the nozzle with some Berryman's B12 carb clean, or soak them for a day.
Then get in there with a kids art paint brush or similar to scrub the opening a bit.
Reassemble.
Hopefully you didn't touch the pressure adjustment Under the big hex cap.
I would reassemble, then loosen the big hex just a tad.
Remove the plug in the center of the hex cap.
Get inside with an allen wrench and turn the pressure adjustment about 1/4 turn clockwise.
99% of the used injectors I rebuild need a slight pressure adjustment to get back to spec.
Usually 1/4 - 1/2 turn inward.

 

[Cm131]

If the pintles pulled out easily you are 99% there already.
Just clean off the tips of the pintles and get down inside the nozzle with some Berryman's B12 carb clean, or soak them for a day.
Then get in there with a kids art paint brush or similar to scrub the opening a bit.
Reassemble.
Hopefully you didn't touch the pressure adjustment Under the big hex cap.
I would reassemble, then loosen the big hex just a tad.
Remove the plug in the center of the hex cap.
Get inside with an allen wrench and turn the pressure adjustment about 1/4 turn clockwise.
99% of the used injectors I rebuild need a slight pressure adjustment to get back to spec.
Usually 1/4 - 1/2 turn inward.

@Ray70
@jamawieb
Thanks for the info and adjustment tip. I have not messed with the top hex or Allen screw. I plan to let them soak for a day or two and then reassemble. I was messing with the flow test and checking timing but after reading more I believe I need to redo checking the timing. I’m was getting confused on where and when PC should line up in reference to the intake valve. If I remember correctly PC lined up just as the #1 intake closed and began the compression stroke?? I will have to recheck but if that is the case I believe I may in fact be out of time. Also can I remove the IP and just check the Oliver guide for cracks and put back on if it’s ok without needing parts?? Thanks again for all the help.

 

[Ray70]

Yes, PC should line up slightly before TDC on cyl #1 compression stroke, shortly after the intake valve closes, but that stuff is mainly irrelevant for your situation because that is all mechanical connections between the cam and crank. It has nothing to do with the timing of the IP's fuel pulses.
You want to perform the "flowing the pump" test to see if pump flow on cyl 1 stops right at the PC mark.
If the plunger guide has skipped, that test will fail completely.
You can disassemble the IP, inspect the plunger guide and reassemble without any new parts, but at that point you would be reusing the old seals and could end up with leaks afterwards.

 

[Cm131]

Yes, PC should line up slightly before TDC on cyl #1 compression stroke, shortly after the intake valve closes, but that stuff is mainly irrelevant for your situation because that is all mechanical connections between the cam and crank. It has nothing to do with the timing of the IP's fuel pulses.
You want to perform the "flowing the pump" test to see if pump flow on cyl 1 stops right at the PC mark.
If the plunger guide has skipped, that test will fail completely.
You can disassemble the IP, inspect the plunger guide and reassemble without any new parts, but at that point you would be reusing the old seals and could end up with leaks afterwards.

@Ray70

Thanks again for getting me straight. I still want to recheck the flow test that I did yesterday but I was getting fuel before PC. Fuel Stopped and I was dead on PC. Then I got fuel shortly after passing PC. Fuel went from solid stream to off and back to solid stream. But there wasn’t much of a window between full fuel, no fuel flow, fuel fuel. If that makes since. So does this mean I’m in time. I’m sorry I’m just confused a little on-how To check the timing

 

[Ray70]

Yes, that sounds correct. You should have fuel flowing, then it will suddenly stop right at the PC mark.
I don't recall how far you have to turn the engine before fuel flow comes back, but it's not very far.
The time when you have no fuel flowing from the pump is the time when it would be sending fuel to the injector instead of circulating through the IP.
However! Now you've got me questioning if a skipped plunger guide would affect the timing or not, I think perhaps not!
The plunger guide is there to rotate the plunger into the correct position to send the fuel to the right cylinder based on which one is about to fire.
The pump flow timing method is only telling you the timing of when the plunger begins to get pushed forward by the cam to start building pressure to fire the injector.
I don't think the rotational position of the plunger will affect the pump flow test, now that I think about it more in depth.
So in other words there's still a good chance your plunger guide could be off and the pump flow timing test doesn't give us the information we need.

 

[Cm131]

@Ray70 Im sorry I don’t need to confuse you also. I will recheck the flow test just to make sure. Do you have a fool proof way for me to check the timing. If I have to remove the pump I just want to make sure I have the parts needed to reinstall. But prefer not to take it off if not needed. Also I’m soaking the injectors while I have them out. I’m trying to build a pop tester but having issue finding the needed fittings. But one thing at a time. I really do appreciate all the advice.

 

[Ray70]

Not your fault.... I was thinking it would show up as a problem with timing, but I guess not. Usually when I see a machine displaying your symptoms I just take the pump out and open it up. That may be the only sure fire way to know. I've seen it so often lately it's just 2nd nature to pull the pump out to have a look inside, it only takes maybe 20 minutes at this point to pull it off and open it up.
Just be sure you have the motor at PC on cyl#1 with an 1/8" pin in the pump alignment slot before removing it. That will take the guess work out of reinstalling it correctly.
Are you building the bottle jack pop tester? That's what mine is.
Had to do a little welding and make a couple adapters to allow me to attach 002/003 as well as 802/803 injectors. But it works pretty well.

 

[Cm131]

@Ray70
Perfect I’ll see what parts I need to uninstall and reinstall plus get a plunger guide just to be safe assuming I can find the parts. As for the pop tester I was planning to go the porta power route as I have several. Just ordered what I think will be the right connections to make the hook-up. I just would like to know where they are as far as pop pressure before I make to many changes and create more variables. I’m personally leaning forwards timing 1st injectors 2nd. As it ran perfect about a week ago for several straight hours. I have plenty of fuel getting to the injectors but seems know that it is firing out of sync or is starved of fuel.