Not pumping fuel (Merc 650)

[hibbert6]

Took my boat out today for the first time this season. I'd pretty much drained the tanks at the end of last August, so I put 2 gallons in one of the tanks (the one that happened to have the fuel hose attached) as this annual run was just to find anything that needs fixing before our boating vacation next week.

The engine ran well at any speed for 1-3 minutes, (depending on speed) then died. The fuel line "bulb" was soft. Squeezed until firm, and it would start right up and run until the fuel in the line ran out. Happened again and again, same cure, same result. At one point, I had my son squeeze the bulb every minute or so to keep fuel flowing, and that worked. So, what does this mean? (Yes, I opened the vent.)

OH, NO!!..I just realized that I did not add oil to those 2 gallons of gas today. Would that have caused the problem? Or was sucking air just God's way of saving my motor from my stupidity?

Thanks in advance!http://forums.iboats.com/editpost.php?do=editpost&p=1375470
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Dave

 

[diaric]

Re: Not pumping fuel (Merc 650)

choices are, fuel pump, bad hose, bad hose connectors, bad lines in engine. or the vent is plugged up. if u crack the cap and it runs ok, then the vents at fault, inspect your connector ends and internal hoses to see if they might be sucking air
fuel pump is cheap to redo, could be some sediment plugging it up a bit

 

[hibbert6]

Re: Not pumping fuel (Merc 650)

OK, Thanks, I'll try these tomorrow.

Can you explain how bad hose, hose ends, etc. might cause the engine (fuel pump?) to stop sucking fuel from the tank?

Thanks!

Dave

 

[diaric]

Re: Not pumping fuel (Merc 650)

fuel hose can get soft when it gets old and the inner layer can collapse in on it self on high suction. if you have a manual it should have pictures to show how to inspect your hose fittings.if they are worn, you can start sucking air and not get enough fuel. just came back from a long fishing trip, my buddies boat with a couple year old poly tank had a bad vent. collapsed the tank. sucked it right in, don't know how the engine stayed running

 

[hibbert6]

Re: Not pumping fuel (Merc 650)

Thanks! Now, I WILL inspect all those in the morning!

Dave

 

[diaric]

Re: Not pumping fuel (Merc 650)

good luck, its probably a simple fix, the trick is finding it

 

[hibbert6]

Re: Not pumping fuel (Merc 650)

Uh -oh...I just realized that I did not add oil to those 2 gallons of gas today. Would that have caused the problem? Or was sucking air just God's way of saving my motor from my stupidity?

Dave

 

[hibbert6]

It Worked!

It Worked!

Well, friends, you were right!

I replaced the fuel hose and bulb (used the old connectors as they were expensive) and it's worked well all this week. Thanks a million!

Dave