2006 F115 Fuel Injector Problem ?

[comptrw]

2006 F115 Fuel Injector Problem ?

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I have a 2006 F115 with only 20 hours on it. I bought it at the end of 2007 new in the crate and installed it myself on my pontoon boat. I had to have it certified by a Yamaha dealer before i turned the key to get the extended warranty. The motor has run great the last 2 summers, but the first time I took it out this spring it cranked and idled fine but had no power under load. The Yamaha dealer recommended replacing the fuel filter and getting the 10 micron inline filter. I have always diconnected the fuel line at the launch and run the engine till it cuts off and when I stored the boat the external tanks were empty. I have always started with fresh fuel in a clean tank, but have no control over what is in the fuel when I buy it. So with all that being said the fuel filters did not help a bit and the second time I took it out it started missing on one cylinder. I assume I have injector problems since the plug is firing. I have noticed reading alot of these forums that this seems to be a common problem with the Yamaha's. I have rebuilt many car engines, but have limited experience with outboards. I am not afraid to tear something apart and put it back together though. Should I just go ahead and remove the injectors and have them serviced ? I feel for sure this is the problem. Any suggestions ??

 

[cousinabe]

Re: 2006 F115 Fuel Injector Problem ?

did you see this post?
you may want to try to soak and clean as an option.

http://forums.iboats.com/showthread.php?t=370721

 

[99yam40]

Re: 2006 F115 Fuel Injector Problem ?

Do you have a Yamaha service manual for your motor?
If not get one you will need it.
I am not up one the 4 strokes but I am sure they have filter and screens on the motors and pumps somewhat like the 2 strokes and could be plugged or partially blocked.
I would think there would be some pressure tests you could do to help troubleshoot in the manual. Pulling the injectors and having them serviced is a good idea. And there are maintenance items yamaha recommends I am sure.

There are lots of opinions on this ,but my thoughts are:
Running a motor till it dies may not be the best way to set one up for any length of time because it leaves some fuel in the system. As that evaporates quicker being less fuel it leaves residue behind and plugs things up. It would be better to make sure that fresh fuel is stabilized and in the system before putting up for storage. It will take longer for it to dry out and cause problems. These outboards need to be run as often as possible to keep them going trouble free.

 

[Silvertip]

Re: 2006 F115 Fuel Injector Problem ?

Do not run an FI engine dry. DO use a fuel system additive like SeaFoam or Stabil. And when you do lay the boat up for long term storage, add the fuel system additive and let the engine run long enough to draw it into the entire fuel system. The fuel pumps and injectors must stay protected or they will become sticky and/or corroded.

 

[seahorse5]

Re: 2006 F115 Fuel Injector Problem ?

When a fuel injected motor is run dry, the electric fuel pump gets damaged and worn each time. Gasoline both cools and lubricates the in-line electric fuel pump and any disruption of fuel flow causes the pump to run hotter than normal plus adds wear to the copper brushes on the armature. Newer Yamaha pumps went to graphite brushes to lessen particles that get into the system as the brushes wear.

Particles from the pump (and any fine debris from the fuel system) accumulate in the injector screens which eventually plug up and/or restrict the flow of fuel. On an inline fuel rail like the 115 has, the debris works its way to the bottom injectors and causes them to act up first.

You should have the injectors cleaned and tested by someone like Flagship Marine in Punta Gorda, FL then the fuel system pressure tested while the motor is running at all speeds to see if the pump or the pressure regulator is damaged.

 

[comptrw]

Re: 2006 F115 Fuel Injector Problem ?

Yes, I accidently posted on this thread and got scolded for not starting a new thread Thats ok I never mind being straightened out.

 

[comptrw]

Re: 2006 F115 Fuel Injector Problem ?

Yes i have a Yamaha manual for my motor. I have the fuel rail off and the injectors out of the rail. I have done the test that Rodbolt suggested in another thread. I took a clear 2 liter bottle and cut a hole in the cap so the injector fit snugly.I used carb cleaner and filled up the injector and connected the jumpers correctly. I bumped the negative lead on the battery and the No.4 injector barely dribbled. No.3 sputtered and they got better as I went up. I would have to conclude the injectors are stopped up and No.4 being on the bottom is definitley the worse. Has anyone used Flagship Marine for injector cleaning. i went to their website and it said $50 per injector retail.

 

[seahorse5]

Re: 2006 F115 Fuel Injector Problem ?

Flagship Marine is where Yamaha tells their dealers to send injectors and HPDI pumps for cleaning.

 

[comptrw]

Re: 2006 F115 Fuel Injector Problem ?

Thanks, i appreciate the info.

 

[comptrw]

Re: 2006 F115 Fuel Injector Problem ?

I sent my injectors off to Flagship Marine and got a great turn around time on them. Cleaned and flushed the rest of the fuel system while I waited on the injectors. The VST was really nasty, had a reddish brown varnish all in it that took a lot of work and a small wire brush to clean it all out. Put it back together on Saturday and took the boat out on Sunday and it ran great. I will never put ethanol fuel in this motor again. I have 2 gas stations near me that tout the benefits of no ethanol fuel and they have made a believer out of me. Thanks for the great forum and the good info I was able to gleen from the many posts here.