Mep 802a

[Broka]

Hey, can anyone assist me with a 802a fermont generator inoperable, i mange to get something going but the big problem i have is that it won't start from the switch has low oil pressure warning light on and the solenoid won't activate i have to hold it in and use a screw driver to short out starter

 

[Toolslinger]

I'm sure the real experts will be along shortly, but until then...
If you have not downloaded the TM's (technical manuals) for the 802a you should do so, and spend a little time trying to read them. They're challenging until you get used to how the military wrote them, but they are excellent, through resources.

Have you ever had/seen this unit running before?

Is there oil in the set?

When you did short it to start, did you register any oil pressure on the gauge? The gauge runs on a different circuit than the one that triggers the warning light, so it's unlikely they'd both be bad.

I just went through a oil pressure light issue. Haven't actually figured out the root cause, but it was either a corroded contact in J&/P& connection, or it was the fault panel. Either way, the wiring harness burned as a result. You don't want that happening I assure you. Once I got that replaced, I found the fault light panel was also bad, so I had to replace that as well.

 

[Broka]

I'm sure the real experts will be along shortly, but until then...
If you have not downloaded the TM's (technical manuals) for the 802a you should do so, and spend a little time trying to read them. They're challenging until you get used to how the military wrote them, but they are excellent, through resources.

Have you ever had/seen this unit running before?

Is there oil in the set?

When you did short it to start, did you register any oil pressure on the gauge? The gauge runs on a different circuit than the one that triggers the warning light, so it's unlikely they'd both be bad.

I just went through a oil pressure light issue. Haven't actually figured out the root cause, but it was either a corroded contact in J&/P& connection, or it was the fault panel. Either way, the wiring harness burned as a result. You don't want that happening I assure you. Once I got that replaced, I found the fault light panel was also bad, so I had to replace that as well.

 

[Broka]

Thanks for responding, i never saw it run because i bought it from the auction, it has oil the oil Guage registered 40psi i don't know where the j&/p& connection is located

 

[Toolslinger]

When you open the control panel door there are 3 black plugs at the back right. That's the area. They disconnect from below if you were ever to need to disconnect them. If I got another machine, I'd probably do it just because, and hose all the contacts down with Deoxit.

Good that you saw pressure on the gauge.
Once you pull the manuals, you want to look for the Oil Pressure Switch, and associated circuit. Start at the switch, and check function, then back along the circuit, and eventually to the relays, and fault panel. Having only worked on my one unit, I can't tell you what's likely to be the cause. There's really good troubleshooting procedures in the TM's.

 

[DieselAddict]

Once you get a chance to peak at the TMs, take photos of the unit and post them up for us to check out.

 

[Ray70]

Do you have the dead crank switch in the normal position and the red E-Stop button pulled out?
It sounds like you don't have power to the control panel.
Do the fuel pumps run when S1 is put in the prime/run position?

 

[Broka]

Yes i have the dead crank switch in normal and the red switch has pull out and also i have power at the panel. Both pump run.

 

[FarmingSmallKubota]

Have you cleared/Reset the faults on the fault panel before trying to start it again?

 

[Broka]

Yes i clear the fault reset and even unplug the wire to but still not starting. I hold in the reset and try crank and all you hear is clicking sound

 

[Toolslinger]

Clicking from the pumps, or something else like relays?

Are both your batteries good? As in really good? One weak battery will give you all sorts of headaches. This is also something I found out the hard way...

 

[Guyfang]

Ope up the control panel. There is a whole line of relays. But one of them is NOT a relay. The one on the far left, is NOT a relay. It LOOKS like one, but its not. So see if all the relays are tight in the socket, and that the far left one is NOT the same as the rest.

 

[kloppk]

Ope up the control panel. There is a whole line of relays. But one of them is NOT a relay. The one on the far left, is NOT a relay. It LOOKS like one, but its not. So see if all the relays are tight in the socket, and that the far left one is NOT the same as the rest.

The leftmost "Relay looking" thing is S14, the Frequency Trip Switch. Inside of it you should see a green circuit board and components on it.
If it's missing or defective it will prevent the starter from engaging when using S1.
K12, K15, K16, K19 & K20 are all relays and are the same part number.
** Edit - better picture with relay functions

 

[Broka]

Hi guys thanks again for the continuous help, i not sure if the two batteries are perfect, i took them out of my crv and frontier these vehicles use everyday and i dont have starting issue with them in the vehicle
When i bought the generator s14 was missing, so i went on the thread and saw someone post the part number to be MJN2CF-DC24, i purchased it and place it in. I didn't check to see if it has any green thing inside

 

[DieselAddict]

That is NOT the correct part number for S14. As noted before, its not a relay even though it fits the same base. Order the correct part from @kloppk and go from there.

MA - MEP-802A, MEP-803A S14 Frequency Trip Switch 5930-01-396-2940, 88-21091

MEP-802A & MEP-803A Frequency Trip Switch - S14 Replaces 5930-01-396-2940, SPS-100-88-21091, 88-21091 · Direct replacement Frequency Trip Relay for S14 for the MEP-802A & MEP-803A I personally assemble each of the S14 Frequency Trip Switch's. Once built each S14 is installed in my MEP-802A...

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