MEP 002a Not producing Electricity, I am looking for someone who is familiar with the 002a to work on it.

[chb32nj]

I have a MEP 002a that I bought from a Gov auction in 2012. It came from Robins AFB and it had 0.9hrs on the meter. It runs great but does not make any electricity. After reading many threads on this site I checked everything I could get my hands on for loose or disconnected wires, nothing is loose. The inside of the control cubicle is clean and no signs of burnt wires, fuses or circuits. I am not an electrician nor do I like doing electrical work, it is not my thing. I think this generator is in great shape but something is not working correctly. My luck it will be one wire I did not see, lol!
I would like to find someone that is familiar with these generators to trouble shoot it for me. I will put it in my truck and bring it to your location and pay you for your services. I am in NJ but I will drive a couple hundred miles if I have to. Thank you.

 

[rickf]

I am right around the corner from you so I can take a look at it, I am in Browns Mills. Send me a pm with some contact info.

Rick

 

[rickf]

PM sent

 

[Chainbreaker]

Just curious if this problem was ever resolved? If so what was the issue? It always good to know the outcome and the repair applied for others that might experience a similar issue.

 

[chb32nj]

Just curious if this problem was ever resolved? If so what was the issue? It always good to know the outcome and the repair applied for others that might experience a similar issue.

I have not been able to find the problem yet. I am still trying to figure it out. I thought it might have been the voltage regulator but now I think it is in the stator.
As soon as I find the problem I will post it right away. Thanks for asking.

 

[Guyfang]

Start it up. Measure at the 120 volt outlet. Any voltage there?

 

[rickf]

I had talked to him on the phone and he has no voltage at all anywhere when running. He did flash the windings during start as per the manual.

 

[Ray70]

Could also be a bad CVT , as well as a half dozen other things.

 

[Chainbreaker]

Rotating Diodes in gen head also come to mind...

If you search in this forum using either "MEP-002a rotating diodes" or "MEP-003a rotating diodes" I am confident you will get some info on how to test to determine if bad and fix if necessary.

 

[Guyfang]

You need to start someplace, so start like this. Open the AC output box. Look inside. Anything burnt, loose, shorted out, rats nest, "spare" parts rattling around or smell funny? Look at the box mounting bolts. Have they been removed? Are they loose? Could mean someone tried to fix it sometime before. Are the cables to the box loose? Screwed in correctly? Not cross threaded? Pins not burnt off. If there is someone near by with a MEP-002A, con them, or better yet, ask them to load you the AC output box. Just to test. Even a MEP-003A box will work for the test. Just don not think a MEP-003A box is the fix. It has one or two small differences. BUT will let the set make voltage. Then I would test/check the rotating diodes. and then the main gen itself. The tests are in the -34 TM. Did you check, and then recheck if the Volt Reg is PROPERLY hooked up? All the wires, in the right spot? No burnt places on the front or back of the card?

 

[chb32nj]

You need to start someplace, so start like this. Open the AC output box. Look inside. Anything burnt, loose, shorted out, rats nest, "spare" parts rattling around or smell funny? Look at the box mounting bolts. Have they been removed? Are they loose? Could mean someone tried to fix it sometime before. Are the cables to the box loose? Screwed in correctly? Not cross threaded? Pins not burnt off. If there is someone near by with a MEP-002A, con them, or better yet, ask them to load you the AC output box. Just to test. Even a MEP-003A box will work for the test. Just don not think a MEP-003A box is the fix. It has one or two small differences. BUT will let the set make voltage. Then I would test/check the rotating diodes. and then the main gen itself. The tests are in the -34 TM. Did you check, and then recheck if the Volt Reg is PROPERLY hooked up? All the wires, in the right spot? No burnt places on the front or back of the card?

I have opened up the control box and looked for anything burnt or loose. Nothing that I see is bad, and I checked all the connections and they are tight. To me, it looks brand new inside the control box. I have another MEP-002a. I bought them both at the same sale. MEP-002a #2 does not run currently. It has the typical IP problem. I have never had #2 running so I don't know that it produces electricity either. I was thinking about switching the control boxes but it looks so clean inside that after I checked the connections I did not think anything was bad. At this point I guess it can't hurt to try it. I will have to start reading about the diodes. I looked at the VR and everything looked good but I did not check the wires for proper terminal location. I will try to do that tomorrow night. I am going to try and post 2 pictures of the control box. Thank you for your help and suggestions.

 

[chb32nj]

Rotating Diodes in gen head also come to mind...

If you search in this forum using either "MEP-002a rotating diodes" or "MEP-003a rotating diodes" I am confident you will get some info on how to test to determine if bad and fix if necessary.

I will start reading about that in the TM. Thank you for your help.

 

[Chainbreaker]

Yes, read up on them in the TM. However, if you use the search function here (at very top of page in the generator forum) using "MEP-002a rotating diodes" you will get several hits on various threads and tips on how to check and install new ones if necessary. Substitute MEP-003a also in your search as the process and parts are the same for either model.

I'm not saying this is your issue but it can certainly be one of many causes that prevent AC output.

Also inside of control box appears good, however one suggestion is: With batteries disconnected put a screw driver on every screw inside there to make sure wire terminals are fastened down tight and not loose, also tug on each wire to make sure it is tight in terminal ring. Being a 2 cylinder engine with both pistons moving in synchronous motion it vibrates the control box quite a bit, if any terminals are loose it could cause intermittent connections. Its just one more thing to eliminate.

 

[chb32nj]

Yes, read up on them in the TM. However, if you use the search function here (at very top of page in the generator forum) using "MEP-002a rotating diodes" you will get several hits on various threads and tips on how to check and install new ones if necessary. Substitute MEP-003a also in your search as the process and parts are the same for either model.

I'm not saying this is your issue but it can certainly be one of many causes that prevent AC output.

Also inside of control box appears good, however one suggestion is: With batteries disconnected put a screw driver on every screw inside there to make sure wire terminals are fastened down tight and not loose, also tug on each wire to make sure it is tight in terminal ring. Being a 2 cylinder engine with both pistons moving in synchronous motion it vibrates the control box quite a bit, if any terminals are loose it could cause intermittent connections. Its just one more thing to eliminate.

I will do that, thank you!

 

[Chainbreaker]

Another thought is that the AC reconnection switch has sat unused for years and might be oxidized and slightly corroded. If so, it is not at all uncommon that you will not get any AC output.

So, with generator off open up the metal panel's cover undoing the captive screw to access the "AC Output Reconnection Switch". Normally for house mode it should be pointing to the right 120/240 mode. But since your unit only has .9 hrs on it it may be set for another default configuration for military use.

See if you can gently at first, rock that switch back-and-forth to get it to rotate to the left to all the other positions several times. It will feel spring loaded like you have to get just the right amount of tension to break it free. If it does not want to move, try a little more rocking back & forth with more effort. But do not put too much force on it to the point of breaking something. Do not put pliars on it to "gorilla wrench it" as you risk breaking the knob off.

If the switch is stuck tight report back here as there is a way to free it up that requires taking off the side panel and loosening the wafer switch screws (not removing them!) to the big wafer switch and then using contact cleaner lubricant to free up switch. Otherwise, you can do a search for that method if you want the info on how to do that.

Good luck!

 

[Guyfang]

Checking the A.C. output switch is a good idea, but can not be the problem, if you do not have 120 volts at the 120 volt outlet. Well, as long as the Circuit breaker for the 120 volt outlet is pushed in, and working. Looking into the AC output box should be the next step.

 

[chb32nj]

Another thought is that the AC reconnection switch has sat unused for years and might be oxidized and slightly corroded. If so, it is not at all uncommon that you will not get any AC output.

So, with generator off open up the metal panel's cover undoing the captive screw to access the "AC Output Reconnection Switch". Normally for house mode it should be pointing to the right 120/240 mode. But since your unit only has .9 hrs on it it may be set for another default configuration for military use.

See if you can gently at first, rock that switch back-and-forth to get it to rotate to the left to all the other positions several times. It will feel spring loaded like you have to get just the right amount of tension to break it free. If it does not want to move, try a little more rocking back & forth with more effort. But do not put too much force on it to the point of breaking something. Do not put pliars on it to "gorilla wrench it" as you risk breaking the knob off.

If the switch is stuck tight report back here as there is a way to free it up that requires taking off the side panel and loosening the wafer swicth screws (not removing them!) to the big wafer switch and then using contact cleaner lubricant to free up switch. Otherwise, you can do a search for that method if you want the info on how to do that.

Good luck!

The AC output switch works fine. It was not frozen when I got the generator. I checked all 3 positions for 120/240 current on the L1, L3, Lo lugs. Nothing. Thanks for the suggestion.

 

[chb32nj]

Checking the A.C. output switch is a good idea, but can not be the problem, if you do not have 120 volts at the 120 volt outlet. Well, as long as the Circuit breaker for the 120 volt outlet is pushed in, and working. Looking into the AC output box should be the next step.

Thanks Guyfang and everyone else for all your help and suggestions so far. Should I pull the AC output box off the other generator and switch it just to see what happens? The good thing is it is plug and play. The same question for the control box? Thanks

 

[Chainbreaker]

Thanks Guyfang and everyone else for all your help and suggestions so far. Should I pull the AC output box off the other generator and switch it just to see what happens? The good thing is it is plug and play. The same question for the control box? Thanks

Yes on the AC output box, since your issue is a "no voltage output" issue and you have that option to swap it. That should eliminate anything inside that box as being faulty. That is assuming your other box is good. I would say a very low probability of both having issues though. If that solves the problem you would then know there needs to be troubleshooting directed to the components inside that box to fix the problem as I assume you would want to get both units running 100%.

If that does not remedy the problem then swapping the Control Panel box should do the same for the components/wiring inside that box.

The only issue here is you are not dealing with anything being "known good" except the unit that has the engine that runs. Which only validates that all the functions/controls/wiring inside the control box necessary to run the engine are verified working. But since you have the luxury of having 2 identical units, module swapping my be the quickest way to pinpoint where the no AC output issue lies.

 

[Guyfang]

And LOOK in the second AC output box, to make sure there is not rats nest in it!