4-stroke running erratically

[backer]

I have a Yamaha F115 4-stroke with approximately 75 hours on it. Recently, the motor began to idle roughly and seems to "load up" on acceleration. If I back off the throttle a little, it seems to catch up, but still runs erratically. The fuel filter shows no evidence of water in the fuel (fresh tank full with WaterZorb in it.) The carbs can't be dirty, since this one's fuel-injected. Any ideas, anyone?<br /><br />I did have to jump start the battery. Could this be a voltage-related problem?

 

[JB]

Re: 4-stroke running erratically

Hi, Backer.<br /><br />What is WaterZorb? Is it a water miscifier like acetone? If so, it may be the source of your problem. Check your Owner's Manual for advice on fuel additives.<br /><br />Install a water seperating fuel filter in your fuel line from the tank, fill up with quality gas, 87 or higher octane, and give her time to purge herself. <br /><br />Let us know what you find. Good luck.

 

[backer]

Re: 4-stroke running erratically

Water Zorb is an additive thst is supposed to remove water from the fuel system. It does not contain alcohol or methanol, so should not be the problem.<br /><br />It's a 53 gallon tank, but I'll run it out and see if it will purge the system.<br /><br />Thanks, JB!

 

[JB]

Re: 4-stroke running erratically

Hi, Backer.<br /><br />No additive can remove water. The best they can do is make it mix in solution or emulsion with the gas. The result is a solution or emulsion that is not pure gasoline. The most common active component in these additives is acetone, which is chemically related to alcohols.<br /><br />Your safest and most reliable way to keep water out of your EFI system is a good water seperating filter.<br /><br />Good luck.