MEP-803A genset no crank

[jaybird67k]

i just aquired a MEP803A with 45 hours on it. Bought 2 new batteries and get no crank from either locations. No prime also. The green lights come on with no prime pump and no crank. Jumped the solenoid and it spins. I also get no test lights except for battle and circuit open or closed lights. The start relay is engaging and I have 25v at starter.
Any help would be greatly appreciated.
Thanks, Jason

 

[Ray70]

By " both positions" I assume you mean the dead crank switch and the S1 start switch?
I's start by confirming your E-stop switch is pulled out, the 7.5A circuit breaker inside next to the F1 alternator charging fuse is pushed in and if those all check out, verify the CR1 diode on the panel in the rear left side of the control cube has continuity through it.
Your description sounds more like no power to the control panel than a no crank situation, although it sounds like your saying the cranking relay is engaging?
It sounds by your description like you have no gages, no fuel pumps, no warning lights as well as no cranking.
Do your panel illumination lights work, or are they dead as well?
Might also want to take a look at the TM, or engine side door on the machine for the wiring schematic.
Look at both the S10 dead crank switch, the S1 main switch and the K2 cranking relay, that shows you the path that power takes when cranking from the dead crank or main switch.

 

[jaybird67k]

By " both positions" I assume you mean the dead crank switch and the S1 start switch?
I's start by confirming your E-stop switch is pulled out, the 7.5A circuit breaker inside next to the F1 alternator charging fuse is pushed in and if those all check out, verify the CR1 diode on the panel in the rear left side of the control cube has continuity through it.
Your description sounds more like no power to the control panel than a no crank situation, although it sounds like your saying the cranking relay is engaging?
It sounds by your description like you have no gages, no fuel pumps, no warning lights as well as no cranking.
Do your panel illumination lights work, or are they dead as well?
Might also want to take a look at the TM, or engine side door on the machine for the wiring schematic.
Look at both the S10 dead crank switch, the S1 main switch and the K2 cranking relay, that shows you the path that power takes when cranking from the dead crank or main switch.

The green panel lights do come on. I replaced a 2 amp fuse that was bad behind the control panel under the 7.5amp push in.

 

[Ray70]

That is your battery charging fuse and should be 30A not 2A, but that should have nothing to do with your problem.
Can you confirm you get the same results with both the dead crank and main S1 switches?

 

[jaybird67k]

That is your battery charging fuse and should be 30A not 2A, but that should have nothing to do with your problem.
Can you confirm you get the same results with both the dead crank and main S1 switches?

Dead crank and panel crank same results.

 

[kloppk]

....The start relay is engaging and I have 25v at starter....

I assume when you say "starter relay" you are referring to relay K2?
If so, you'll want to see if terminal A1 on it is getting 24 volts all the time.
Then check terminal A2 for 24 volts when you try and engage the starter from the Dead Crank Switch or S1.

You may have multiple issue since the Primary Fuel pump doesn't run.

 

[jaybird67k]

I assume when you say "starter relay" you are referring to relay K2?
If so, you'll want to see if terminal A1 on it is getting 24 volts all the time.
Then check terminal A2 for 24 volts when you try and engage the starter from the Dead Crank Switch or S1.

You may have multiple issue since the Primary Fuel pump doesn't run.

Thanks. Do I check voltage with relay still installed or pull it out and check the pin slots?

 

[kloppk]

The Start relay is NOT in the row of relays behind the gauge panel.
These are the relays and functions of the relays in that row.






The START relay K2 is located in the AC compartment which is behind the wall where the relays above are located.
You need to take the roof panel off to get to it.
This is K2

 

[kloppk]

The K2 relay is known to get corroded inside causing it to not close causing the no crank problem.
They can be disassembled and cleaned to correct that.

 

[Guyfang]

First I would suggest that you download the TM's, and start reading them. Then you will know where such things like K2 hide in the set. And how to get at it. Might not hurt to take a few pictures of the control panel, the inside of the control panel and maybe the S10, (dead crank ) switch. Perhaps we can see things you dont know about yet.

 

[jaybird67k]

The Start relay is NOT in the row of relays behind the gauge panel.
These are the relays and functions of the relays in that row.
View attachment 929656





The START relay K2 is located in the AC compartment which is behind the wall where the relays above are located.
You need to take the roof panel off to get to it.
This is K2
View attachment 929657

Thanks this helps a bunch.

 

[jaybird67k]

First I would suggest that you download the TM's, and start reading them. Then you will know where such things like K2 hide in the set. And how to get at it. Might not hurt to take a few pictures of the control panel, the inside of the control panel and maybe the S10, (dead crank ) switch. Perhaps we can see things you dont know about yet.

It came with manuals but what is this TM you speak of?
Thanks, Jason

 

[Guyfang]

TM = Technical Manual. The TM's that came with your set may not be newer than what is in the TM forum. You should go to the Generator TM forum, down load the TM's there and compare them. And then spend some time reading the operators TM.

 

[jaybird67k]

TM = Technical Manual. The TM's that came with your set may not be newer than what is in the TM forum. You should go to the Generator TM forum, down load the TM's there and compare them. And then spend some time reading the operators TM.

I found my problem I believe. This unit sat in a field on a pallet for a year since last run. A rat built a nest and chewed close to 20 small wires so I'll be fixing them and go from there.

 

[Light in the Dark]

Not the first... definitely not the last. Do yourself a favor and look up rodent proofing in this forum, for the tips and tricks. Glad the set didnt burn up because of these chewers.

 

[kloppk]

TB-3 is one of their favorite places to build a nest. Bastids!

 

[peapvp]

This is quite mind baffling how rodents can chew through Airframe Type 2 wire, which was invented to carry humanity to the moon and back and to keep jet aircraft in the air……

 

[Guyfang]

I once helped get a 1 million dollar radar ready to go back to Mama Raytheon. Mice got into it in the winter. Total loss. 1 million bucks. The wires all over were chewed through. At last, a mouse got caught in the Magnatron, and the radar burned like a camp fire.

 

[Light in the Dark]

This is quite mind baffling how rodents can chew through Airframe Type 2 wire, which was invented to carry humanity to the moon and back and to keep jet aircraft in the air……

 

[peapvp]

I once helped get a 1 million dollar radar ready to go back to Mama Raytheon. Mice got into it in the winter. Total loss. 1 million bucks. The wires all over were chewed through. At last, a mouse got caught in the Magnatron, and the radar burned like a camp fire.

@Guyfang
Wait until @Light in the Dark ‘s Russian Field Mice get in there….

Maybe we should send some of those Magnatron’s to the Ukraine