MEP-831a Troubleshooting

[PETE01]

This started all of a sudden. The governor just appears to lose power and fall in between overriding the mechanical governor or shutting down. When in this condition, the magnet does not capture the target, and the governor does not override the mechanical governor.

When I turn the switch to the off position, all the guages go to zero and the engine seems to go on slightly slower idle. When I toggle it back to on, the engine seems to rev up just a little, but nothing else happens. Once in a while, the generator goes back to normal state. I'm thinking that I have a loose connection somewhere.

When this condition happens, the unit still produces voltage, but when I put the unit under load, the circuit breaker opens.

If I latch the governor to the manual start position, I get lots of power at the speed controller and plenty of power at the lugs. Works just fine under load.

Thanks for your help, Chris. I real all 300 posts on this thread. This has been the best info on these great little gensets.

 

[DieselAddict]

Certainly check for loose connections. That is always the first thing to run down. Check for 24v DC power at the governor module when you have the "RUN" switch on. Make sure power to the governor follows the "RUN" switch position correctly.

Before this happens does the generator regulate engine speed correctly? Pay close attention and see if anything else subtle is out of whack. Check the engine RPM to load relationship.

When the governor modules begin to fail they will do a number of odd things like you are describing. I've seen that behavior as well as unstable RPM after a unit runs for a while.

 

[Guyfang]

I have only seen two gov failures on this set. And the problems you describe, were symtoms I saw while repairing those two sets. Having said that, my experience with the 831A is limited. When the 831A runs right, its a nice set.

 

[PETE01]

I will check all my connections. From the above comments, I understand that the controller itself may be at fault. I read from the early posts that getting a new unit from the manufacturer was crazy expensive and you had mentioned building something yourself.

Have you had a chance to pursue your project?

I am thinking that worse case scenario, the generator could be set to run at constant speed with the mechanical governor set at 3450 RPM with the mechanical governor start/stop knob. The electric governor could be replaced with a plunger or other small linear actuator and wired to the off switch. In this way the generator could be started and stopped from the switch, which is the only thing that's important after all.

Weather the engine runs at 3050 RPM or 3450 RPM only makes a difference in terms of fuel consumption and noise. In the civilian world, it should not be a big deal. The plunger could also be wired in the K2? circuit to cut off in case of any faults.

The electric governor and the magnet are elegant solutions but it looks like the government "made 3 left turns instead of one right turn" again...

Your thoughts?

 

[DieselAddict]

I have a prototype going. I've not been able to work on it for the last year because I'm on a big engineering project that is 3000 miles from home. I'll be on the project through Sept of 2017. I won't be able to make any real progress on it till I get back home.

Of the 6 MEP831 generators I've bought at auction 4 of them have had bad governor modules.

 

[AfghanVeteran2010]

Of the 6 MEP831 generators I've bought at auction 4 of them have had bad governor modules.

Makes me wonder whats killing them.

 

[Guyfang]

I just posted in the manuals upload section simple instructions on how to setup and adjust the governor for the MEP-831A. I think its easier to follow then the TM, and if you print it out, (its one page) easier to look at then the TM or computer screen. Got it from a "friend". Thanks dude!

 

[ted50]

Thank You Guyfang!!! This is so much easier to understand than the TM.

 

[PETE01]

Maybe I didn't drink enough coffee this morning, but where is this instruction sheet? I looked in the manuals and did not find anything.

 

[Guyfang]

Look in tm upload, or go to forum and look at threads started today. At some time, the TM upload will be sent to the TM section, but for now, just look at the latest threads started.

Guy

 

[Guyfang]

Look in tm upload, or go to forum and look at threads started today. At some time, the TM upload will be sent to the TM section, but for now, just look at the latest threads started.

Beter known as "Today's Posts"

Guy

 

[kloppk]

As of now it can be found here: http://www.steelsoldiers.com/showth...le-Governor-setup-and-adjustment-instructions

 

[PETE01]

Got it. Great summary. Thanks.

If only I had a responsive Speed control module, it would be great. i took my 2 old modules and stuck them under an incandescent light bulb for a week. They stayed nice and warm in hopes that any moisture inside the potting would find its way out. I know these generators were left outside, some of them for years, and it turns out the load speed controller appear to be sensitive to weather conditions. I haven't had a chance to see if this fixed the problem yet but I'm not too optimistic.

I found one source for new parts (WB Parts) who quoted $473.21 for a new speed control module. I found another one who wanted north of $700. That's a little high in my opinion so I'm looking for alternatives. I googled the NSN Number and I found a manufacture in New Jersey, Polytech industries who obtained a contract to make some modules for the government a few years ago. I emailed and they responded them but they don't seem too much in a hurry to provide a price. I asked for a price for (2) two and I think that they blew me off... Might be a good idea to try to organize a group buy.

I tried Ebay, no luck and I think that getting a used speed controller is a crap shoot as they are probably all failing.

Guyfang mentioned that it's a good idea to shed the the load before turning the generator off. I think he might be on to something. I think my generator started acting strange after I shut it down without first opening the circuit breaker. I don't know what else could have happened.

I still think there's a better way to skin the cat with these governors. This is an awfully complicated way to get from point a to point b.

 

[Guyfang]

Its always a good idea to shed the load before turning off a gen set, not just this one.

 

[ted50]

Hi,
I fine tuned both of my 831's using Guyfangs new TM and they are working great. I have a meter that has a frequency setting but the readings I get on the A and B terminals are in the 800 range. It works fine on my shop receptacle [60hz] and on my 803 but not on the generators. I had to use the VAC settings. My question is -Am I using the meter properly in the frequency mode? I think I read somewhere on here that the leads had to be disconnected? Also why is the HZ reading better than the VAC reading. Again thanks to everyone. This site is invaluable. Enjoy the festive season!!!!
Ted

 

[dav5]

Hi I have been reading all the generator posts for the MEP831a and downloaded the TM's. I used Guyfangs set up TM and have the generator operating as it should except for one thing. It shuts down fine which it wouldn't before but the magnet won't release to restart. My friends generator releases the magnet as soon as it is switched to the run position. When I first got it the magnet was set at about 2 lbs. I adjusted it to as close to 5 lbs as I could. Any advice would be appreciated. Thanks

 

[Dewie38]

The magnet should not pop off when the start switch is in the run position.
Because you have a low oil pressure fault there is no power to the actuator.
What should happen is as you crank the engine by placing the start switch to the start position the oil press will start to build up and when you are in the start position all faults are bypassed, the actuator should get full 24 volt control power for a split second and the actuator should move to full fuel.
This could take a while of cranking to happen.
By the way...Guy's procedure that he posted is the procedure I wrote for the tech manual and for when I was training the soldiers on using the 3 kW.

 

[Guyfang]

Dewie!

Did not know you wrote that. I would have given you credit for good work, had I known. I got it from a CECOM guy I know a while back, in 2010??. Cant remember. I found it on my lap top computer, and posted it. If no one else will say thanks, I sure will!! Take care and hope your New Years is a nice one!!!!!!!!!!!!!!!!!

MFG,
Guy

 

[dav5]

Dewie!

Did not know you wrote that. I would have given you credit for good work, had I known. I got it from a CECOM guy I know a while back, in 2010??. Cant remember. I found it on my lap top computer, and posted it. If no one else will say thanks, I sure will!! Take care and hope your New Years is a nice one!!!!!!!!!!!!!!!!!

MFG,
Guy

Thank you both for all the information you have posted over the last while. It has been a real help. Dieseladdict has been a great source of info too. I will try cranking it longer. The low oil warning light was on.

 

[dav5]

OK Dewie I cranked it for a long time and the low oil pressure light went out fairly quickly. I continued to crank it until I was afraid I would overheat the starter. The magnet just won't release. If I manually pop the target it starts right away and operates beautifully with smooth acceleration and runs fine with 2 heaters and 2 drills connected which registers about 3.2 KW on the load gauge. It shuts down with no problem.