2002 yamaha 115 v4 problems

[Jeffrey Green]

Having problems with it running at full throttle.I think I'am having a vapor lock problem or fuel pump problem.Motor is on a 1900v bay sea pro with built in 37 gal tank.When it gets to half of tank of fuel it bogs down when you try to go full throttle.Hooked to a portable 6 gal. tank today and it ran great,hook it back to built in tank ran bad,hooked it back to portable tank and then it still ran bad,so now I'am leaning towards fuel pump problems.ANY HELP WOULD BE NICE.I have replaced plugs ,fuel line and bulb,cleaned fuel filter.

 

[Jeffrey Green]

Re: 2002 yamaha 115 v4 problems

Any idea's

 

[DadTo2Marines]

Re: 2002 yamaha 115 v4 problems

If you can run off the small tank, and use half of your large in boat tank, without any problems it's not your fuel pumps. It sounds like your fuel pickup in the tank has a hole in it. Pull it out and take a look.

 

[Jeffrey Green]

Re: 2002 yamaha 115 v4 problems

Okay,I've replace fuel line and bulb,fuel pump,fuel filter on motor,and installed a water fuel separater on boat.Pumped out all old gas out of tank,checked fuel pickup tube for obstruction,it was clean.Tested boat today and at first it did'nt run good at all then all the sudden it cleared up and ran like hell turning 5800 rpm and flying for about 45 min.then we hit a big wave and something happened it started bogging down again like it was'nt getting any fuel,I could take the manual choke on the front of motor and pull it out about 1/4 inch and it would clear up.Does anybody have any idea was going on with this motor.

 

[triumphrick]

Re: 2002 yamaha 115 v4 problems

Have you cleaned the carbs? Have you tried to Sea Foam the tank and the engine? The rig I recently bought had been sitting since last Fall, and after spending some time on the forum and using search fuctions, I had repeatedly found users had good luck with Sea Foam. I tried it and with a variation of the application it really cleaned up carbs, carbon, etc.

Google Sea Foam and it will take you to their site. I bought it at Advance Auto. The instructions tell you to use 1/3 in tank, 1/3 in crankcase and 1/3 in inlet vacuum hose. Don't need the crankcase, so put appropriate amount in tank. Poured rest into a atomizing spray bottle and fogged it into each of my three carbs, on a warm motor, while my son kept the revs up so engine doesn't die. Once in the motor, turn off, let sit for 5 mins.
Restart with revs up. Smokes like hell!! All good tho'. Stuff works.
Seems that since you get some good results with the choke, should be carb related, so give this stuff a shot.
Use search for Seafoam...see what some others have done with it.

 

[Jeffrey Green]

Re: 2002 yamaha 115 v4 problems

They were cleaned in march when I bought the boat by the dealer I purchased it from, but I don't think they really done it.

 

[Jeffrey Green]

Re: 2002 yamaha 115 v4 problems

Please Help Somebody