oil injection and mixed fuel

[cruisersveesport]

i have a a ski that is oil injected, the previous owner put a new engine in a year ago. He ran mixed fuel and left the injection system intact. His reasoning was he would never have the worry of the injection system failing. It would just smoke a little, can this do any harm to the ski or is a good idea to use mixed fuel and run the oil injection also

 

[liquidlew]

Re: oil injection and mixed fuel

On a brand new engine you are supposed to run extra oil for the break-in period, so that would be fine running premix plus the stock oil injection. After the break-in you can just quit using premix and just use the stock oil injection.

On my Yamaha's I have disconnected the stock oil injection systems and just run 50 to 1 premix, I now don't have to worry about an oil pump failure (although I've never heard of one breaking), or an oil line coming off the carb, if that happened while you were running you wouldn't know it until it was too late. I also now don't have to clean up spilled 2 stroke oil off my ski from overfilling the tank cuz it's hard to see the tank and fill it at the same time.

Running premix is not any more of a hassle than dealing with an injection system, the oil is in the fuel so you don't have to worry about mechanical failure or a loose oil line. I use a Ratio-Rite cup and add about 12-1/2 ounces of oil into a 5 gallon jug, fill it with fuel so it mixes, then pour it into ski.

Happy riding!

 

[H20Rat]

Re: oil injection and mixed fuel

running premix + injection CAN be bad... More oil means less fuel in the cylinder, but the same amount of air. Adding extra oil means you are leaning out the engine. Might not be a problem unless you get some crappy fuel or are already close to detonation.

 

[haulnazz15]

Re: oil injection and mixed fuel

You can also foul out the plugs, especially on 2-stroke models if you have too much oil in the mix. Think about it: you have 50:1 premix in the tank, and the oil injection system is putting in oil to try and mix roughly the same amount. You just doubled what the manufacturer set as optimal. You may not see as big of a difference at high speed or WOT, but you WILL notice it when it comes down to idle or get out of the hole. Starting will be considerably more difficult as well.

Oil injection systems don't have a high fail rate, so I wouldn't mess with premix unless you 1)know your oil injection system is bad, or 2)disconnect the oil injection system completely and just run premix.