MEP-804A Shutdown on Under Voltage, now won’t start

[Jdj211]

How full is your primary fuel tank? Aux fuel pump should only start running when your primary is down to 1/4 tank, and shut off when it gets to 3/4 tank. Is the aux line clear and hooked up properly at both ends?

I haven’t even gotten to the point of hooking up the aux tank yet. The issue is that when I turn the switch to the prime/aux/run position from the prime/run position the entire set shuts down as if it had been turned to the off position.
I understand that the aux fuel pump won’t run until the day tank is around 1/4, but I can’t even keep the set running with the aux mode active to see when it cuts on/off.

 

[peapvp]

@Jdj211

You need to check the S1 Circuit Schedule in this diagram.
Either the S1 switch is defective or corroded or one of the wire(s) is on the wrong terminal or one of the jumpers are missing.
The Diode CR5 is only active during start for Pre Heat.

 

[Jdj211]

@Jdj211

You need to check the S1 Circuit Schedule in this diagram.
Either the S1 switch is defective or corroded or one of the wire(s) is on the wrong terminal or one of the jumpers are missing.
The Diode CR5 is only active during start for Pre Heat.

I will study this circuit. But looking at the switch terminals themselves I’m a bit lost. I’m not sure which screw terminal corresponds with which number on the diagram. It looks like there were some numbers stenciled on the phenolic discs near some of the screws, but they are not legible. Any guidance on determining which screw corresponds to each of the numbered terminals in the diagram?

 

[peapvp]

I will study this circuit. But looking at the switch terminals themselves I’m a bit lost. I’m not sure which screw terminal corresponds with which number on the diagram. It looks like there were some numbers stenciled on the phenolic discs near some of the screws, but they are not legible. Any guidance on determining which screw corresponds to each of the numbered terminals in the diagram?

That is sort off an uphill battle and maybe the cause off this. Someone previously may have tried to repair this unit and ran into the same issue you are experiencing.
The terminal numbers are usually printed on the switch next to the terminal.
They are hard to read most often and you may want use a strong flashlight and a magnifying glass.
As I am getting older, these two tools have become mandatory when I work on terminals.
I am just grateful that I am not a presidential candidate…….

 

[Jdj211]

I figured a video would demonstrate better than my description. You can see the generator is running and producing power. I should be able to turn it back to the prime/aux fuel and run to pull from an external fuel tank while it is running, yet it shuts down when I do so. I’m not sure how well it comes through on the video, but I can hear the appropriate clicking of the aux fuel pump in this position, so at least that appears to be working appropriately.

IMG_9821.MOV

drive.google.com

 

[Jdj211]

That is sort off an uphill battle and maybe the cause off this. Someone previously may have tried to repair this unit and ran into the same issue you are experiencing.
The terminal numbers are usually printed on the switch next to the terminal.
They are hard to read most often and you may want use a strong flashlight and a magnifying glass.
As I am getting older, these two tools have become mandatory when I work on terminals.
I am just grateful that I am not a presidential candidate…….

I will take a closer look with a better light.

 

[Guyfang]

One of the wires on the S1 appeared to be "strange". Like it was twisted, Maybe broke. But you have to check the switch AND wires. The attachment is the diagram for the switch.

 

[peapvp]

One of the wires on the S1 appeared to be "strange". Like it was twisted, Maybe broke. But you have to check the switch AND wires. The attachment is the diagram for the switch.

@Guyfang
I am not sure, but I think the diagram you posted is for another switch style, the newer square version.
He got the older style 2 level switch like from the 00 hundred series meps

 

[Guyfang]

In post #19 it shows a picture of the new square S1.

 

[peapvp]

In post #19 it shows a picture of the new square S1.

@Guyfang
Ah, ok, didn’t see the square mounting plate in the picture

 

[Guyfang]

My seeing eye dog alerted on it. I am sitting here wrapped up in my blankie, sipping warm milk and searching for my store bought false choppers!!