MEP-003a DC circuit breaker troubles

[Uloadit]

I had the gen running and the neg cable fell off and the engine started to die .I ran over to but it back on and i got a big spark and it still shut off.went to restart and it keeps poping the push button shut off, i can turn it to the glow plugs ok but i cant turn it on at all and keeps poping the fuse. what did I do? now i am bumming out!

 

[armytruck63]

We need a little more information, like what kind of generator you are talking about.

 

[Uloadit]

I am sory it is a mep003a your avatar , its kool. did the starter short out

 

[RichardR]

Uloadit

Apparently, something on the DC 24 Volt power buss has failed resulting in a short to ground. This happened almost surely as a result of a voltage spike on the buss when the neg connection to the battery fell off. You'll have to track it down by disconnecting things one at a time until the short goes away. I would start by disconnecting the fuel pumps at the connectors (are those called Packard connectors?) in the wires hanging below the control box.

I'll bet you will find that one or more of the fuel pump EMI filters has developed a hard short to ground. If you are lucky, the pump itself will still be OK and you can run your genny without the EMI filter(s).

If that's not the problem, I'd next suspect the battery charging regulator. But that doesn't sound like the symptoms you are seeing.

Best of luck,
Richard

 

[Uloadit]

where are the emi filters located

 

[RichardR]

They are each mounted by a metal tongue under the bolts holding the fuel pumps to their bracket. To unground them, just take out the bolt and suspend the EMI filter in air by its wires. Keep the fuel pump grounded if you want it to work.

 

[Uloadit]

yes your the man! I have the auxiliary pump and run pump so now it starts and runs but the one that pops the fuse is the one next to the gen what does that one do? should i fix it and what do to fix that do i need it AND THANK YOU SO MUCH!!

 

[RichardR]

The pump next to the gen is the second of two pumps that work in series to feed fuel to the filters. You might be able to run the genny on just one pump by disconnecting the power to that pump, but I have never had much luck doing that. In any case, you CAN operate without the shorted EMI filter simply by cutting it out of the power line and connecting the two wires together.

 

[Uloadit]

can i fix that one ? is the short in the little box on the side or in the round part if i can not fix that one where can i get another one

 

[RichardR]

The short is in the little box (the EMI filter) and not in the round pump. I don't think the shorted EMI filter can be fixed, at least with reasonable effort. And I don't know where to get another one without also buying the pump. The pump and EMI filter are sold together as an assembly even though they are simply connected by a wire. Maybe someone knows where to get just the EMI filter. The assembly is made by Facet and is available for purchase. You could do us all a big favor by contacting Facet and asking them if they sell only the EMI filter or the pump individually. I need 3 of the EMI filters myself.

Regards,
Richard

 

[doghead]

You can simply remove the round part and reconnect the wire . I used a butt connector to splice mine, when I removed the filter.

RR, great diagnosis!

I've experienced the same failure when I ran an MEP-002 on a slave cable and it came unplugged while it was running.

 

[Uloadit]

yes he knows his stuff ! I took off the box off the frame and it works now but i cant let it touch the frame or it will short out. Can I just cut out the box and tye the wires back together ?

 

[Speddmon]

I'm going to give this thread a better title. "Now what did I do?" doesn't quite help anybody else out who actually searches the site for answers. Inaccurate or non related thread titles are one of the big reasons the search feature on this site is in the sad shape it is in.

I'm happy to hear you got your set running again. Good luck with it.

 

[doghead]

yes he knows his stuff ! I took off the box off the frame and it works now but i cant let it touch the frame or it will short out. Can I just cut out the box and tye the wires back together ?

Yes

 

[NJ_Toolnut]

Kudos to RichardR!