yamaha 115 two stroke salt water series

[marcel1444]

engine runs rough after the boat is bouncing around in the ocean . If I shut the engine down and fish for a while the engine seems to run good. Could water be in the fuel and getting mixed with all the movement? If I take the boat on the river I don,t seem to have the same problem. when I increase the throttle the engine bogs down and runs very rough. Please addvise. Thank you!! Marcel

 

[bossee]

Re: yamaha 115 two stroke salt water series

Hi,<br />Connect a small external gas tank with fresh gas.<br />If it runs OK then it is probably some problem in the boats ordinary fuel supply.<br />Possibly water in the gas tank.<br /><br />Have a look at the spark plugs. If water has been entered in the fuel system the spark plugs usually seems very "clean". You can have a look here how a "healty" spark plug should look like:<br /> Link <br /><br />Do You have a water/gas separator installed?<br />Like this:<br /><br /> Link <br /><br />A 60 GPG filter will work fine.<br />You do not need to buy a Yamaha filter and You do not need a probe but a clear bowl is nice to have. A Racor will work also, like this:<br /><br /> Link<br /><br />The 320R-RAC series will be fine.<br /><br />So I would start with running on an external gas tank with fresh gas. If it runs good then I would probably install a fuel/water separating filter (unless You have it already) or if You have it and the filter element has not been changed in long time I would get a new replacement filter element.<br />I would probably pump out the old gas and use it in a car and fill new fresh gas in boat fuel tank. That is because if there is much water in the gas tank in your boat the fuel/water separator will quickly be full and You need to drain many times before the tank will be empty of water.

 

[CLL2437]

Re: yamaha 115 two stroke salt water series

Marcel, I have the exact same problem as you have. My Yamaha 90 runs great on the lake but in the bay it starts to cut out and bog. I can’t get the RPMs over 2200-2300 until I shut the motor down for a little bit. I can shut the motor off for 10 seconds and restart it and it will be fine for a while. I was told the motor was going in to RPM reduction mode. I never had the alarm go off when it happens so I don’t think it’s an over heating problem. I have replaced the entire fuel system from the tank to the pump and everything in between. I was thinking about rebuilding the carbs and checking the reeds. I really believe the extra bouncing around has something to do with the problem. I’m still trying to track down the problem and plan on rebuilding the carbs within the next few days. I’ll keep you posted on what I find.

 

[marcel1444]

Re: yamaha 115 two stroke salt water series

thanks for the ideas!! I have a little more info. I am wondering if something is getting stuck in the engine. when we push the throttle foward to max,the engines rpm drops to say 2300 or 2400 rpm then runs rough. Just like CLL2437.Is it possible for linkage to get stuck. Choke to get stuck? I drained the tank as much as I could and added new fuel. At the end of the trip I had the same results With the RPMS. Acting like a fuel problemm. Iam convinced it is not.

 

[marcel1444]

Re: yamaha 115 two stroke salt water series

Wondering if they have a computer that can be hooked up to the engine to get a read out as to what is happening to my 1997 yamaha 115 hp two stroke salt water series motor S115TXRV. When I bought the boat someone said that they can tell how many hours are on the engine buy checking with the computer and getting a read out.

 

[rodbolt]

Re: yamaha 115 two stroke salt water series

if you ever get trash or water in the carb bowls you cant get it out. you can usually flush water out by removing the carb drain screws,. trash normally has to be removed manually after removing the fuel bowl. I would pull the drains and the main jets and have a look.