briangrandlake
New member
Hi all! I have a 2000 SeaRay SunSport 28 footer with 7.4 Mercruiser Mag engine, Bravo 3, only 150 hours on boat/motor. Motor starts cutting out after I get it on plane. Bogs down, backfires, etc. Pull back on throttle and it runs great. Here is everything I've done to this point and no change in symptons:
Added 35 gallons of fresh non ethanol fuel to tank
Replaced fuel water separator, poured fuel into clear jar and had zero water in it
Then filled filter up with seafoam and started motor to let it suck it all in
Replaced all spark plugs with the AC plugs motor calls for, gapped to .35"
Pulled Cap and Rotor, I thought this was my issue because it had white crusty stuff on all the contacts, but made no difference
Found vacuum line detached, I assume from the fuel pump. It was just laying under front plenum, so I zip tied it back on, no difference
I'm next going to get a fuel pressure gauge and attach to that schrader valve I found and see what it shows, at idle, and full throttle when the issue begins.
Also, when it gets on plane it will then start backfiring, sputtering, but never dies. I can pull back on throttle and it runs great. It starts fine, idles great, etc. My water temp is running over 170 so I have a new water pump on order and will replace it. I'm running out of ideas, hoping it's not a bad fuel pump but the fuel pressure gauge should tell me what's going on with it. Perhaps a clogged fuel injector or 2? Boat did sit for 1.5 years without being used, badly broken femur I been recovering from.
My motor s/n is 0L68138 and every online parts catalog indicates I should have the inline electric fuel pump with that cooling tube, yet when I was inside the engine compartment on the port side (I believe that's passenger side
), I see at the bottom back side of the motor by the motor mount, a black round pump. I'm assuming that's the mechanical fuel pump??
Anyone have any ideas I should try that I haven't thus far? If it is a bad fuel pump, and I have the mechanical version, how much of a PIA is it to replace that thing? I'm damn glad I've lost over 40 pounds over past 6 months, getting in/out of that engine compartment is much easier now Thanks!
Added 35 gallons of fresh non ethanol fuel to tank
Replaced fuel water separator, poured fuel into clear jar and had zero water in it
Then filled filter up with seafoam and started motor to let it suck it all in
Replaced all spark plugs with the AC plugs motor calls for, gapped to .35"
Pulled Cap and Rotor, I thought this was my issue because it had white crusty stuff on all the contacts, but made no difference
Found vacuum line detached, I assume from the fuel pump. It was just laying under front plenum, so I zip tied it back on, no difference
I'm next going to get a fuel pressure gauge and attach to that schrader valve I found and see what it shows, at idle, and full throttle when the issue begins.
Also, when it gets on plane it will then start backfiring, sputtering, but never dies. I can pull back on throttle and it runs great. It starts fine, idles great, etc. My water temp is running over 170 so I have a new water pump on order and will replace it. I'm running out of ideas, hoping it's not a bad fuel pump but the fuel pressure gauge should tell me what's going on with it. Perhaps a clogged fuel injector or 2? Boat did sit for 1.5 years without being used, badly broken femur I been recovering from.
My motor s/n is 0L68138 and every online parts catalog indicates I should have the inline electric fuel pump with that cooling tube, yet when I was inside the engine compartment on the port side (I believe that's passenger side
), I see at the bottom back side of the motor by the motor mount, a black round pump. I'm assuming that's the mechanical fuel pump??Anyone have any ideas I should try that I haven't thus far? If it is a bad fuel pump, and I have the mechanical version, how much of a PIA is it to replace that thing? I'm damn glad I've lost over 40 pounds over past 6 months, getting in/out of that engine compartment is much easier now
Thanks!