Main start switch dead Mep-802

[Ranger Danger]

I've been using my MEP-802 for my off grid property for about 3 years. Its been great! Ran the gen for about 10 hours about 2 weeks ago to charge the RV batteries, watch TV etc. Went back to the property about 1 week later to find the main start switch dead (no clicking no lights no nothing). I was thinking dead batteries as a first step. Pulled both batteries to find a full charge and load tested good. Time for a head scratch. Went to the bypass start switch in the engine compartment and motor turns over great but no start even with main start switch in run position. Checked the fuel to find an empty tank. I have an external 100 gallon tank (with 50+ gallons in it) but both my wife and I occasionally forget to put start switch in aux tank setting. Never ran out before. I refilled the primary tank. The main start switch is still dead (no clicking no lights no nothing). I suspect that I will have to reprime the motor but shouldn't the main start switch be powering up? Also, is the starter 12V or 24V? I'm running 2 12V Napa gold batteries. I want to be sure the batteries got put back in correctly (series or parallel).

Can I connect the aux tank line to the line out of the main tank to bypass the main fuel tank so as to not run out of fuel again or is there a low fuel shutoff sensor in the main tank preventing this?

 

[Zed254]

24 volt system. Check TM to confirm battery wiring is correct. Dead Crank functioning implies proper battery connection. Did you fill tank with Aux fuel pump - it is 24 volts? You should hear the main fuel pump come on when you put Master Switch in Prime/Run position: any sound? Is your generator rodent proof?

 

[Ranger Danger]

Got it. I put them back in the way they came out and the engine turns over well. Ill check them again just to be sure. Thanks

 

[Ranger Danger]

No sound at S1 at all! I refilled the tank from a 5 gallon jug. Its as rodent proof as I can get it. Its mounted inside a "wind and water tight" shipping container. Doors are always closed.

 

[Zed254]

Got it. I put them back in the way they came out and the engine turns over well. Ill check them again just to be sure. Thanks

Is your main fuel pump square or a cylinder? Cylinder type are considered better pumps. Is S1 a plastic blue switch or metal? Might be as simple as exercising the S1 with some contact cleaner. Could be a loose wire inside control cabinet, too.

 

[Ranger Danger]

I opened all the compartment doors and the front panel. No evidence of rodents or bugs.

 

[Ranger Danger]

Is your main fuel pump square or a cylinder? Cylinder type are considered better pumps.

Dont know. Could you provide a pic of both so I could tell for sure?

 

[Ranger Danger]

If you are referring to the pump in the tank, its round.

 

[Zed254]

E switch pulled out? Dead Crank in Normal position?

 

[Zed254]

If you are referring to the pump in the tank, its round.

This is considered the better pump.

 

[Zed254]

Once electrical power to S1 is established you will probably need to prime your fuel system (main pump) for a few minutes if the fuel ran dry.

 

[Ranger Danger]

E switch pulled out? Dead Crank in Normal position?

S1 is dead even with dead crank in normal. I'm going back up there today so I will check to see if the E switch is set.

 

[Ranger Danger]

Will reprime if needed. Thanks for all the help, Ill report back on Sunday.

 

[Ray70]

Check the DC circuit breaker inside the control panel, right next to the gray fuse holder for the alternator, make sure it hasn't popped out.
It's the black button mounted to the bracket sticking out to the left of the AC select switch.

 

[Zed254]

but both my wife and I occasionally forget to put start switch in aux tank setting.

Can I connect the aux tank line to the line out of the main tank to bypass the main fuel tank so as to not run out of fuel again or is there a low fuel shutoff sensor in the main tank preventing this?

Not sure about this: I like the system as set up by military. If your fuel tank gauge is properly functioning - and you observe the control gauges at startup - it will act as a reminder to refill the onboard tank. If fuel gauge is broken....like mine was.....here's a cheap replacement: https://armysurpluswarehouse.com/military-issue-fuel-gauge/

 

[Ranger Danger]

Check the DC circuit breaker inside the control panel, right next to the gray fuse holder for the alternator, make sure it hasn't popped out.
It's the black button mounted to the bracket sticking out to the left of the AC select switch.

Will do, Thanks.

 

[Ranger Danger]

Not sure about this: I like the system as set up by military. If your fuel tank gauge is properly functioning - and you observe the control gauges at startup - it will act as a reminder to refill the onboard tank. If fuel gauge is broken....like mine was.....here's a cheap replacement: https://armysurpluswarehouse.com/military-issue-fuel-gauge/

When using the aux tank, it just keeps the main tank full but if S1 is in the main position instead of the aux position, it will run the main empty.

 

[Ray70]

Your main tank has a combination float in it that works both the aux. pump as well as tripping the "low fuel" warning light and it shuts off the fuel pump when you get almost empty, so you can't just move the lines around, you would need to bypass the low fuel warning circuit.
Now, if you were out of fuel and the warning light did not come on or shut the gen off, then you also have issues with that system as well.
Once you get the control panel working, push the " push to test" button on the warning light panel to make sure it's plugged in and lights are good. You may have a problem with the float module or the actual fuel float in the tank.
Out of curiosity ( or maybe I missed it ) when you turn S1 do your gages move at all? I'm not clear if you have no power at the panel or just no fuel pump or starter function. You can also try the glow plug and see if that clicks to verify if you have any power at S1.

 

[Guyfang]

Do you own a multi meter? If so, I think we can shorten this troubleshooting process.

 

[Ranger Danger]

Your main tank has a combination float in it that works both the aux. pump as well as tripping the "low fuel" warning light and it shuts off the fuel pump when you get almost empty, so you can't just move the lines around, you would need to bypass the low fuel warning circuit.
Now, if you were out of fuel and the warning light did not come on or shut the gen off, then you also have issues with that system as well.
Once you get the control panel working, push the " push to test" button on the warning light panel to make sure it's plugged in and lights are good. You may have a problem with the float module or the actual fuel float in the tank.
Out of curiosity ( or maybe I missed it ) when you turn S1 do your gages move at all? I'm not clear if you have no power at the panel or just no fuel pump or starter function. You can also try the glow plug and see if that clicks to verify if you have any power at S1.

S1 is dead no clicking no lights no pump noise...nothing. The float module in the tank was replaced about 2 years ago. When I discovered what looked like an empty main fuel tank, I put about 4 gallons in it and it was full so, I'm not so sure it ran to empty.