Fuel Pump?

[egaito]

So, the new battery charger is in, and we're ready to leave the slip, but I wanted to do oil changes before we left, and cranked the girls up to warm the oil.

The starboard engine began to struggle at idle after a minute or two, and finally stalled....wtf? I restarted, listened, advanced the throttle, and eventually it stalled.

The gauge on the racor didn't show any more vacuum, so on a whim, I turned on the priming pump, and she came back to life and ran fine, until I shut it off, at which time she stalled again.

So, I'm thinking I'm dealing with a failed fuel pump.

Any other ideas before I pull it? Any tips on the job?

Thanks,

 

[OBXTucker]

Any chance you still have air in the fuel line?
Is the fuel filter full after stalling?
Try starting it from the engine room with the line from the fuel pump to the fuel filter off and see if it's pumping from the racors. Just put a cup under the line to catch any fuel that is pumped, if any.

My fuel pumps are different for each engine, ones a left rotation, the other is right. If you need to replace, make sure you get the correct one. Not sure which engines you have.

 

[egaito]

Any chance you still have air in the fuel line?
Is the fuel filter full after stalling?
Try starting it from the engine room with the line from the fuel pump to the fuel filter off and see if it's pumping from the racors. Just put a cup under the line to catch any fuel that is pumped, if any.

My fuel pumps are different for each engine, ones a left rotation, the other is right. If you need to replace, make sure you get the correct one. Not sure which engines you have.

Does the pump not "pull" through the racor?

I pulled the canister off of the engine filter, and while there was stuff in the bottom of the canister, the filter looked fine.

If I can figure out which line is "out" from the fuel pump, I'll pull that one and see if it's pumping, but if it's not the pump itself, there has to be an obstruction somewhere.

They're 9v92TI's.

 

[OBXTucker]

TI's are over my head, but I agree it sounds like you have an obstruction or air in the line. Sure, it could be the fuel pump, but I'd check down the line first.

Others with more experience will chime in I'm sure...

 

[TopHattandTails]

Is the fuel draining back from the Racor to the tank at all? Maybe you have fuel in he secondary filter, but some air in the Racor from "drain back". She starts on the fuel in secondary, but stalls before reprimed from air in Racor. How much fuel do you have in the tanks? The lower the level, the quicker she'll drain back. If this is happening, I'd bet on a fuel pump going bad. Keel tanks act like siphons with anything less than perfect fuel pumps.

 

[saltshaker]

Sounds like the Racors are leaking fuel back to the tank. Before you start the engines again, open the Racors and see if they are full to the top. If not, they are allowing fuel to return to the tank. Very common and easy to fix. You can take them apart and clean the ball check valve. I would order a rebuild kit and redo them.

 

[Pascal]

Fire it up with the priming pump, let it run a few minutes, turn off the pump. When it dies Open the racor and check if it s full

If it stalls right away when you turn the pump off, I d guess the pump is bad

If it keeps running for a while I d lean for air being sucked in

I forgot how the priming pumps are plumbed on sanctuary but the engine driven pump is between the primary and secondary. Secondary is under pressure. I d Change it anyway, when was it changed last?

 

[Pascal]

And recheck the oil, smell it to make sure you don't have fuel in the oil, the pump can leak into the crankcase

 

[Canuck Dennis]

Place a small mirror under the fuel pump, crank the engine and you can see if the pump is actually turning, if it is, problem elsewhere

 

[aquaddiction]

I had teh same problem on my port engine 8v92TI where I had warmed up, threw the mooring lines off and STOP!

After thinking the worst, running through the basics, checked racors were clear, I ran the electric fuel priming pump for 5 minutes and overcame the issue.. My problem was bleed back of fuel after being moored for a long time and solid period of circulating fuel to tank cleared the air bubbles. As teh GM's run a common rail with full pump pressure up to your injectors, much of the fuel will circulate back to the tank.

If you have given it a good run on the electric pump and it wont run without it it sounds as though you are up for a fuel pump rebuild.First things first crack the fuel line on the rail before the injectors and see if you are getting any flow while cranking

 

[oldawg]

My boat has a crossover/return line after both filters with a one-way check valve. If that valve gets stuck the engine will pull air from the return side and starve the engine. Spent well over $2k with Cat mechanics and fuel polishers before I found that $8 check valve.