Generator stopped working, seems starved for fuel, can I add an electric pump

[Looking Glass]

My Northen Lights 20kw generator stopped working suddenly. I am almost certain it is a fuel starvation problem. I checked all the lines and there is no blockage. If I use the manual pump on the fuel pump, as if I were bleeding the system, the generator will run for a few minutes, then die. I assume it is just running out the fuel that I manually pumped in.

I cranked the engine with the line off the fuel pump and it pushes a little bit of fuel out, but not much.

In between the fuel pump and the racor is what looks like either a electric pump or perhaps a shut off solenoid. I have no idea. It has four wires going to it. I have attached a picture.

Does anyone know what this is? I though perhaps the manual pump needed an electrical assist pump because the resistance of a long run to the fuel tanks, plus the racor in between.

 

[Looking Glass]

I have since bypassed what ever that is in the picture. So, if it is a shut off, it is not the problem. If it is an electric pump, it might be the issue.

 

[Pascal]

Could that be a priming pump?

If it runs using the mechanical priming pump I would suspect the electric fuel pump.

Edit... brain fart. The NL20s have mechanical fuel pumps not electric

How many hours on the racor and on the secondary? I always start with fuel filters when troubleshooting a diesel

 

[racclarkson@gmail.com]

If you've bypassed your electrical thingy (fuel lines), does the unit now run? The fuel pickups for generators are higher than those of your engines so gennys will starve out before mains. So how much fuel do you have in your tank that feed the generator? If its low, transfer some fuel and see if the problem goes away. I have the same unit, BTW, and never needed an fuel pump. The mechanical fuel pump is a diaphragm pump. Manually supplying fuel with the lever should indicate a good pump. You may be just sucking the last little bit with the priming lever.

 

[SEVEN]

Don’t bank on the fuel gauges to be accurate. I agree with Robert.

 

[jim rosenthal]

The only thing predictable about those tank gauges is their inaccuracy. If you're lucky, they will be consistently inaccurate; if you're not, they will be inaccurate AND inconsistent.

Would gravity feeding from a temporary tank be useful? Seems like if it would run that way, the lift pump may be faulty.

Also, I have that generator set up as my home standby set, and that little lever on the pump takes a LONG time to prime the fuel system. I added a squeeze bulb and a manual shutoff so it didn't lose prime.

 

[Looking Glass]

Thank you all for responding.

Our tanks are full so that is not the issue. I am going to try a small container of fuel, close to the generator and see if that helps.

I have checked on various forums and with other boaters, and no one seems to know for sure what the thing in the picture is.

 

[racclarkson@gmail.com]

Thank you all for responding.Our tanks are full so that is not the issue. I am going to try a small container of fuel, close to the generator and see if that helps.I have checked on various forums and with other boaters, and no one seems to know for sure what the thing in the picture is.

if that electric pump isn’t pumping then its stopping the flow. Bypass it.

 

[Looking Glass]

if that electric pump isn’t pumping then its stopping the flow. Bypass it.

I did bypass it. It did not help.

 

[Looking Glass]

Update:

I ran a fuel line from the mechanical fuel pump straight to a small can of fuel sitting next to the generator. And now it works fine.

So, either the unidentifiable thing is an electric assist pump that has failed, or there is something further down the line clogging the fuel lines. I did not think it was the second issue because I can blow through the lines and hear air bubble in the open racor.

In any case, I plan to keep moving the small can of fuel further down the line (bypassing the racor) and see if the generator will still run.

I have attached a couple more pictures of the part. When I blow through it I can hear something spinning. Perhaps it measures the fuel rate? And, I found an identical part on the return lines.

 

[davidwigler]

Update:

I ran a fuel line from the mechanical fuel pump straight to a small can of fuel sitting next to the generator. And now it works fine.

So, either the unidentifiable thing is an electric assist pump that has failed, or there is something further down the line clogging the fuel lines. I did not think it was the second issue because I can blow through the lines and hear air bubble in the open racor.

In any case, I plan to keep moving the small can of fuel further down the line (bypassing the racor) and see if the generator will still run.

I have attached a couple more pictures of the part. When I blow through it I can hear something spinning. Perhaps it measures the fuel rate? And, I found an identical part on the return lines.

View attachment 31811View attachment 31812

If the same part is in the return line it sounds like a fuel flow meter maybe a Floscan. Never heard of those for a generator though.

 

[racclarkson@gmail.com]

OK, it pulls from a bucket, the paddle wheels are from a flow meter and the tanks are full. Your fuel line is blocked or it's got a leak and picking up air. I don't suppose you've noticed bubbles in the Racor? Good seal on the Racor lid? You can blow back from Racor to tank and see if it's a clog; maybe also take line loose at tank and check there too. If it won't stay lit then, you can add a section of clear hose where the fuel line from the Racor transitions to metal and look for air. A vacuum gauge is helpful.

Since the flow meters are not standard, is it possible they were installed with teflon tape? May a bit have broken off and moved up stream?

I'm betting some air will clear the fuel line and you'll be fine.

 

[davidwigler]

OK, it pulls from a bucket, the paddle wheels are from a flow meter and the tanks are full. Your fuel line is blocked or it's got a leak and picking up air. I don't suppose you've noticed bubbles in the Racor? Good seal on the Racor lid? You can blow back from Racor to tank and see if it's a clog; maybe also take line loose at tank and check there too. If it won't stay lit then, you can add a section of clear hose where the fuel line from the Racor transitions to metal and look for air. A vacuum gauge is helpful.

Since the flow meters are not standard, is it possible they were installed with teflon tape? May a bit have broken off and moved up stream?

I'm betting some air will clear the fuel line and you'll be fine.

Or the lift pump is not strong enough to pull from the tank. The diaphragm could be bad. My Kohler has an electric lift pump and I replaced it for under $100.

 

[racclarkson@gmail.com]

Or the lift pump is not strong enough to pull from the tank. The diaphragm could be bad. My Kohler has an electric lift pump and I replaced it for under $100.

Yep, possible. But LG was able to hand pump it, and that's the same diaphragm moving lots slower by hand. Still, it's possible. Also a ruptured diaphragm could be leaking into the motor. Better check the oil.

I don't recall the boat model posted. I'm wondering if, as stated, the tanks are full that fuel isn't gravity feeding the Racor as it would do in mine with a clear fuel line.

 

[davidwigler]

The floor of my generator room is well above the top of the fuel tanks.

 

[Texastailboard]

Sounds like a blockage or it’s sucking air. If it does run how is the smoke? Will it put around on low load? As it was said before bypass that thingy, see what happens. Check both your feed and return lines it can be as small as a seep that’s causing the troubles.