130 Yamaha powers out

[Keelbar]

130 yamaha loses power (bogs down) at higher power but not all the time<br />some days works great, but other days it might start acting up right away or half way<br /> through day<br /><br />I have had it to a shop where they - checked compression, head gaskets, cleaned carbs, <br />new plugs<br /><br />I myself changed ignition coils, boots, plugs, checked connectors, cleaned entire fuel system<br />(hoses, tanks, filters, carbs, etc...)<br /><br />I changed the CDI units 2 years ago because when it went the motor wouldn't even idle. It <br />ran great up until this problem showed up. I think it has to be electric the way it comes and<br />goes.<br /><br />Anything else I should try?

 

[rodbolt]

Re: 130 Yamaha powers out

hello<br /> rebuild or replace the fuel pump. you may also try a vacum gage on the ful inlet and monitor fuel system vacum to check for restrictions, yammis need a pump rebuid as do mercs about every three years or so.<br /> good luck and keep posting

 

[jim dozier]

Re: 130 Yamaha powers out

You might try running it on a portable tank with a different fuel line(or a different tank and fuel line if it already is on a portable) to rule out tank and fuel line problems.

 

[Keelbar]

Re: 130 Yamaha powers out

Hello thanks for the info <br /><br />I have tried running it on a separate portable directly to motor to rule out tanks etc...<br />I have not done anything however with the fuel pump other than to dissassemble and look at <br />insides, didn't see anything obvious. The motor is a 1993 and has given me great years of service, however RODBOLT you say the fuel pumps go so I will check that out.<br />Thank you

 

[Keelbar]

Re: 130 Yamaha powers out

One other thing I forgot to mention was that I have tried the choke switch when it bogs down<br />and by bumping the choke switch it will increase rpm momentarily and a few times brought the <br />rpm up somewhat. I don't know if that means much?

 

[elcamino12sec]

Re: 130 Yamaha powers out

Bumping the choke and RPM going back to normal (what you describe as hi RPM) usualy indicated a possible lean condition, you say the fuel system has been checked out and so have the carbs, I would try the fuel pump first, should be able to do that your self in a hour or two. If thats not it, I would look at the carbs again, possibly getting a little trash in one or two causing a disruption in the fuel flow to one of the cylinders, making the RPM drop slightly or a slight "bog", had the same problem wit a 85hp Suzuki, I went through the carbs about 7 times in the 4 years I had that boat, the last time, it took me 45 min, to go through the 3 carbs, but each time, I would find just one tiny piece of something in the neele in seat or one of the jets, I know, its aggervating.

 

[Ray Loxterman]

Re: 130 Yamaha powers out

As ELCAMINO12SEC mentioned it could be small particales of dirt in the carbs. I highly recommend adding a water seperator filter inline. After you install the filter and run the engine for a couple of trips, you can remove the filter and pour all of the fuel from the filter into a glass jar, let it settle for a few hours and see if there is any trash in the bottom of the jar. Sometimes it is prettry obivous, some times very minute particles. I was absolutly amazed at what I found. It sure has save me many headaches ($$$) over the years.

 

[arkansasboatman]

Re: 130 Yamaha powers out

A couple of things you might try: First, if it is a fuel pump problem, when the smothering starts squeeze the fuel bulb with your hand to pressurize the carbs. Most times this will fill the carb bowls and the engine will run normally. Second, I use an oil squirt can filled with 50:1 premix, remove the cover and air box have someone else drive the boat, when the engine starts smothering start squirting gas into the carbs one throat at a time, you will know when you hit the lean one as the engine will pick right up. That will be the carb giving the problem. Good luck.

 

[Keelbar]

Re: 130 Yamaha powers out

Thanks for tips I will try those. I do run a RAYCOR inline fuel filter and find they work really well.<br />I will keep you posted.

 

[Keelbar]

Re: 130 Yamaha powers out

Ok I ran it today with air box off and found that squirting fuel in the #2 throat on top carb brought the engine rpm back where as squirting fuel in the rest of them had little effect on rpm. So I quess I have a problem with #2. I also squeezed the primer bulb but found it hard throughout the higher rpms.

 

[arkansasboatman]

Re: 130 Yamaha powers out

Looks like you have found the faulty carb. As far as the fuel bulb, you are trying to apply extra pressure to the fuel system to force fuel through a faulty fuel pump and keep the float bowls full so the engine will run properly. Good diagnostics and good luck with the repair.