MEP-002a fuel pump issue?

So on my MEP-002a generator I am turning the start switch to "Prime Run AUX" and I get a normal sound of a fuel pump running. When I switch it to the next clockwise position of "Prime Run" I don't hear a fuel pump running and I hear what sounds like a relay clicking? I am trying to figure out what might be wrong with this newly acquired MEP-002a generator. I have primed it on the "Prime Run AUX" position and started the generator. It will stay running after starting and leaving it in the "Prime Run" position. Any help would be greatly appreciated.

See if you have power to the pumps.

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Scoobyshep said:

See if you have power to the pumps.

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It has a three pin connector on the pump. A,B,C pin. Do I check A,C and B,C with my multi-meter?

24v+ to chassis on P61D16 AND P61F16

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Not sure I understand your issue...are you saying it won't start & run if you start it in just the "Prime & Run" position that it will only start when you first put it in "Prime & Run Aux Fuel"?

It is normal to hear a fast paced clicking if you have the switch in the Aux Fuel position if you don't have an auxiliary fuel tank connected to the Aux fuel pump as there is no fuel to prime that pump. It is also normal to hear a slow click (yes it does sound a bit like a relay clicking) when the main fuel pumps have fully primed the system.

Also, be sure to let the oil pressure build to a steady pressure on the gauge before releasing the start switch. It is ok to hold it in "Start" position for several seconds after it starts as there is a starter lockout that prevents the starter from continuing to engage after it reaches a certain RPM.

Regarding operation of the 3 onboard fuel pumps, the Aux pump only pulls fuel from an auxiliary source (Jerry Can/Auxiliary fuel tank) and only pumps fuel when the day tank drops to about 1/4 full to refill the Day Tank. The Aux pump does NOT pump fuel into the fuel filters & on to injection pump. So if your unit is starting & running you can rest assured that at least 1 of the 2 main pass-through pumps is pumping fuel. There are 2 main fuel pumps for redundancy and must be matched units that have the pass-through provision in case one malfunctions.

Have you read the Technical Manuals for this unit?

It doesn't sound to me like you have a problem at all. Everything Chainbreaker said is spot on.
I'd say your fuel pumps are acting correctly, you just may not be familiar with their normal operation.

Chainbreaker said:

Regarding operation of the 3 onboard fuel pumps, the Aux pump only pulls fuel from an auxiliary source (Jerry Can/Auxiliary fuel tank) and only pumps fuel when the day tank drops to about 1/4 full to refill the Day Tank. The Aux pump does NOT pump fuel into the fuel filters & on to injection pump. So if your unit is starting & running you can rest assured that at least 1 of the 2 main pass-through pumps is pumping fuel. There are 2 main fuel pumps for redundancy and must be matched units that have the pass-through provision in case one malfunctions.

Have you read the Technical Manuals for this unit?

Click to expand...

I haven't read the TM's for this generator yet. Thanks for your response and explanation of how those fuel pumps operate. It just sounded odd switching between the AUX pump which sounded like a normal fuel pump to me with the humming noise the switching to the main pumps with the relay clicking noise. I assumed that something was wrong as I am really not that familiar with these gen sets. I believe that from what you said, everything is working as advertised on this generator. Thanks again. These things seem to be built like tanks.

RTB