MEP-804A Military Generator

[@2naturesownplace]

@Beef if I remember my training right when those first came out I was a power generation specialist back in the '90s and early 2000 s for the army. Turning the panel lights on was as quickest way to test to see if all circuits were working properly. And if you want to make those super quiet the army way of doing it was once in place stack sandbags around it and board the top and over the top and you could barely hear that thing 15 ft away

[@tobyzahn9943]

My 15kw fermont MEP 804A has a 10 lead marathon lima mac head. I had a pretty good surge during the hurricane in 2020 and resulted in not cranking. I finally replaced the motor controller, runs 1800 all day long now, and no elec output. I have replaced the diodes in the excitation rectifier. I have the 10 leads from the Gen head itself configured for WYE High 240VAC, but there are 2 smaller wires labeled F1 and F2. This model lima mac says self regulating and self exciting but F2 by the diagram ends up on position 1 of the external voltage regulator. I am in the process of working backwards through all of the failsafe relays to find out in the end what F2 is connected to. It has to be 24 volts but is it intermittent? Applied by solenoid at startup? Or is it constant while running? If anyone could help, I would forever be indebted. At 9:20 you explained leaving in start to avoid undercurrent. Does it hurt to continue running in the start position?

[@michaelconroy8060]

Step one. Make sure the unit is properly grounded. Then, divide and conquer! remove f1 and f2 wires from the exciter stator. take a 12v battery and apply 12VDC to the F1 and F2 terminals MOMENTARILY using jumper wires. Polarity doesn't matter. watch the voltage output when you touch the 12 volts to those terminals. If you build voltage, you have a problem with the regulation circuitry. if you don't build voltage then the problem is internal to the alternator assembly. Could be exciter stator, exciter rotor, rotating rectifier assemblies, bad rotor or bad stator assembly. More often, it's a regulator problem as alternator assemblies are pretty robust. If it's in the regulator end, the first check would be to thoroughly clean the voltage adjusting rheostat. That's the weakest link.

[@chris76-01]

What does it mean if the little red diagnostic lights don't work when pressing the test button?

[@mmrbeef]

Does the generator run? I’m not an expert by any means but I would think you have a main power problem.

[@javidgunraj1500]

Is the sensor for transfer pump also with the fuel level gauge? Mine doesn’t read fuel level.

[@mmrbeef]

For the 804’s yes it is. I had to replace mine when I first got it. It kept throwing a fault. There are some really good technical manuals for these online. Reading through those manuals has been a money and time saver.

[@themaniacmower]

Thats a cool generator.

[@rongray4118]

Looking for one for off grid system in Northern Nevada

[@josephpuchel6497]

Hey nice GENY I’m looking to get 802a. I can’t do auction thing so I’m looking at private person selling. Found 802a , 1/5 hours, no resets, 2009 year. He wants $3500. The pictures unit looks clean. What are these unit going at ? Thank you for any assistance Thank you

[@mmrbeef]

It’s so hard to track prices on these units. About the only help I can provide is some private ads (no known sales). Locally I have seen two ads for 802’s both ads have been up for several months and are $3500 and $4250. That tells me the private market for the 802’s isn’t that high. Personally for 5kw I can’t justify much more than $2,000-2,500.

[@macp721]

Hi is it ok to paint the outside of the generator in black

[@mmrbeef]

I see not reason why it wouldn't be OK. These come in dark green as well.

[@RocknDirt]

Can't get L1 to power up. Any Help?

[@kamrankhan-dn8sl]

How to clear high temperature code of ten seventy generator?

[@mmrbeef]

I honestly have not idea on the newer sets with the LCD displays. The forum Steel Soldiers might be able to help, I have gotten a lot of helpful hints from there.

[@Djkyle65]

How does one find one like this?

[@mmrbeef]

You can buy them at government surplus auctions (which have become very expensive), keep a look out on FB and Craigslist. You just have to keep a look out. There has been a huge uptick in the price of these units in the last 12 months.

[@williamfranklin6283]

I have one for sale in Baltimore area if your interested.

[@davidhenderson3400]

What does something like this cost?

[@mmrbeef]

Recently good running low hour 804’s are selling on the open market for $6,000 and up. Dead are out there but few and far between. A year ago they were 40-50% less. Obviously there are cheaper examples that sell but it seems these units and the 803A’s have become a big ticket item in the last year.