View Full Version : 2005 Merc 50hp efi outboard starving for gas, help!

10-06-2011, 01:34 PM
As the title says 2005 Merc 50hp efi outboard on a 22' pontoon. While running at any speed the motor will starve for gas. If you squeeze the primer bulb 2-3 times it picks up again and runs.
I have changed the filter/seperator, replaced the primer bulb and hose assembly with OEM,replaced the check valve at the fuel tank, and checked / tested the tank pickup for leaks or cracks. It has a 30gallon tank with 10 gallons of gas in it.
While I was winterizing the motor it started to tick. It sounded like a valve train noise. But as soon as I squeezed the primer bulb the noise went away. Fuel pump?? Anyone have any ideas? Thanks in advance, Mark

10-06-2011, 03:21 PM
I have seen a few issues with the fuel pump on those motors. I think that is your problem. They run about 85.00 if it is in the serial # group that I think it is.

10-06-2011, 06:07 PM
Thanks bearrassler, that is sort of what I was thinking. I have 1 more question. When I bought all of my parts, the dealer gave me a fuel /
water seperator and another fuel filter. But I can't find it on the motor.
Are there 2 filters?

10-06-2011, 06:59 PM
There should be an inline filter and a filter by the fuel pump, what is your serial #?

10-06-2011, 11:14 PM
If it is the white plastic fuel filter with a nipple on each end you are referring to it is located on the port side of the engine. It is down towards the bottom of the engine. It has a black sleeve over it that you have to slide back to access the filter. Your fuel pump on the back of the engine is your problem. It is operated off one of the rockers and that is why it is ticking cause it is not pumping fuel. It will do the same thing if it is run out of fuel. These pumps have been an issue with these models.

10-07-2011, 06:51 AM
Bearrassler, ser # OT683782
Polarismike, Yes the filter has hose barbs on each end. Is it pain to replace that filter? And the fuel pump your talking about also has a coolant line running thru it,correct? If it is the pump is it just a bolt on deal? Sort of like old small block chevy fuel pumps? And should I change the filter if I am changing the pump? Thanks for all the help so far guys!

10-08-2011, 12:44 PM
skidoo50, 25226Here is a parts breakdown of the fuel pump, #1 is the complete pump and #15 is your filter, there is still the inline filter also that you refered to with the barbs on both ends. You should replace both filters and your fuel pump in my opinion.

10-09-2011, 05:53 PM
Yes that is the fuel pump with the cooling lines running through it. Yes you should change the filters also. That lower filter is easier accessed sometimes by splitting the lower cowls apart to gain access. About 5 or six bolts that hold the halves together. Just be careful you don't pinch any wires or hoses when you put the lower cowls back together.