MEP-831a Troubleshooting

[OverkillTASF]

It is definitely the 1500 watt heater. That outlet is only rated up to I think 10 amps, your heater is about 12.5 amps. It is a "convenience" outlet, and doesn't come anywhere close to supporting the power output of the generator or even a standard home circuit.

 

[Cord]

Yea, that outlet is only good for 1000 watts. Try testing it with something else. If it still trips, disconnect the wires to the outlet. If it holds, then the outlet is bad.

Connecting to the main terminals is super easy. Just follow the diagram.

 

[Guyfang]

Buggsy,

The GFI is only supposed trip if you have something plugged in that is defective. Or, if you have voltage going outside of the normal path, or going to ground. So, could your heater be bad? Is the 110 volt plug on the gen set bad? Have you taken the GFI out, hooked it to an outlet in the house and then hooked a load to the output side of the GFI? That's the only way to test it indapendlenty of the 831.

 

[buggsy458]

That was problem! I thought that the heater was less than 10 amps but it isn't so I just ran a fan for about 30 minutes with no problems! Thanks guys you are geniuses!

 

[Guyfang]

Good to go!

 

[bsstephe]

FYI, Read through tons of information on this thread, all very useful but figured I would look for some other fuel side issues. This may have been mentioned somewhere along the way but I didn't pick up on it reading the posts. I have a MEP-831A that had horrible governor oscillations. I replaced the drain back hoses from the main fuel tap, injection nozzle, down to the tank and fixed the issue for good. The long run of line to the tank had collapsed and was keeping back pressure on the nozzle and pump. This hose looked otherwise perfect. Any of you that have dealt with the disintegrating JB pump governor ring issue know that back pressure on the drain back causes many issues. I hope this is useful to someone as there is yet another reason to have this stability problem.

 

[ted50]

I am having governor problems and have read the adjstment sequence many times. I am still confused about the 5/16 measurement between the lever plate and the governor actuating lever. Would anyone have a photo of where the measurement is taken. The info on this site is invaluable. Thanks

 

[ted50]

For anyone needing a 24 V battery a guy on the big auction site has the Concorde battery. He has it listed as an aviation battery but it is the one for the 831 with normal posts. The one I got was in the original mint box. It showed 25% charge when I got it but 6 hours on my NOCO got it to 100%. It was built in October 2014 and he wants $145 shipping included. It is a great battery.

 

[Cord]

I am having governor problems and have read the adjstment sequence many times. I am still confused about the 5/16 measurement between the lever plate and the governor actuating lever. Would anyone have a photo of where the measurement is taken. The info on this site is invaluable. Thanks

You will need to go through the adjustment sequence several times as later adjustments will throw the early one off.

The gap is referring to the space between the target and the magnet.

 

[ted50]

You will need to go through the adjustment sequence several times as later adjustments will throw the early one off.

The gap is referring to the space between the target and the magnet.

Thanks again Cord. When I read the posts on the govenor it was clear that was where everyone meant but then I read the TM and the references to the diagrams don't show the target and magnet at all.

 

[Cord]

The TM assumes the adjustment of the target magnet is beyond the capabilities of the field mechanic. Based on what the mechanic had done to my engine, I doubt he was qualified to wash windows.

 

[ted50]

Yes I agree. The generator that works beautifully had only 2.9 hours on the clock and was missing nuts on the guages, missing fittings on the oil drain a broken fuel cap and all four of the battery cable set screws on both machines were only finger tight. The 2nd generator had only 22 hours after a Reset and had all kinds of problems. The engines and generator heads were both spotless and were obviously very low hour units. It is a shame that they are sold with such an obvious lack of maintenance. If the government put even minimal effort into getting them serviceable the payback would be huge.

 

[R Racing]

Remember the lowest bidder gets the work in the world of the government.

 

[ted50]

That is the sad truth for sure

 

[Guyfang]

The stories I could tell about Reset. Folks, Reset can be good. But its often something a little less. Take the word of Reset with a grain of salt.

 

[PETE01]

Hello:

Trying to diagnose my MEP-831a. I had this thing running like a top. All voltages at the speed controller were in spec. Suddenly, unit would not stop with the switch any more. Voltages at A/B, B/C, C/A read 152 volts. Engine runs slowly.

No problem at the fault lights.

This is an intermittent problem.

Any ideas about what is going on would be greatly appreciated.

Thanks,

Pete

 

[AfghanVeteran2010]

Hello:

Trying to diagnose my MEP-831a. I had this thing running like a top. All voltages at the speed controller were in spec. Suddenly, unit would not stop with the switch any more. Voltages at A/B, B/C, C/A read 152 volts. Engine runs slowly.

No problem at the fault lights.

This is an intermittent problem.

Any ideas about what is going on would be greatly appreciated.

Thanks,

Pete

Sounds like your throttle plate thumb screw might of come lose (part 10), mine gets come lose often. If not then the TM would be the best place to start TM 9-6115-639-13&P. page WP 0013 MALFUNCTION 7 (ENGINE FAILS TO STOP WHEN START/RUN/STOP SWITCH IS PLACED IN STOP POSITION OR EMERGENCY STOP BUTTON IS PRESSED)

 

[Cord]

On occasion my magnet still gets out of adjustment. It's an exceptionally fine line where the unit won't surge and the magnet has enough pull to shut the engine down. Even tightening the nut is enough to throw the adjustment off. If it's only an occasional problem, the easy solution is to just pop the cover open and push down on the lever. Yea, it's not supposed to be shut down this way, but messing with the magnet could throw it further out of adjustment.

 

[PETE01]

The mechanical governor and the plate are all in good shape. No loose parts. There seems to be an event, which causes the voltage on A/B/C to drop down to 150 volts. When that happens, the speed load regulator becomes unresponsive. Seems to happen more often in cold weather. I'm thinking that there is a fault somewhere in the K12 fault relay, where the electric governor becomes de-energized by some fault not shown on the fault lights. Then out of the blue, it starts to work ok again. This one's a real head scratcher!

 

[DieselAddict]

Can you describe the events in the sequence as you know more?

Does the magnet capture the throttle target and the engine continues to run or does the magnet not capture the target?
If you flip the "RUN" switch back on does the generator pick up and control speed again?
What happens if you cycle the "RUN" switch on and back off?