It can't be this easy. Premix question. Why wouldn't this work?

[97SPX]

Okay, I'm sure there is a very good reason why this is a bad idea but I'm just curious why this would not work. If you have a Seadoo and are worried about accidental oil starvation and want to convert it to premix, what would happen if you just filled both the gas tank and oil reservoir with premixed oil and gas? I would think the carbs would just mix the two tanks together as normal and then it would still end up burning straight premix. I figure it has something to do with the oil pump or jets or sensors.

Just curious.

 

[kustomkarl]

Most seadoo Oil injector systems use a Variable rate injector system. The oil is injected at different rates as the rpm's raise or lower. The oil injector pumps calibrated to use a specific weight and API gravity oil to maintain it's injector rate at a given rpm. It would not prove any purpose to have extra fuel and oil in the injector and pre-mixed fuel in the tank except burning more oil ...premixed at 40:1 plus injector will only waste oil and cost more... than the plugs will get fouled more often too...this adds to the expense.

Karl

 

[97SPX]

That makes sense, I figured there'd be a reason. Once I get my DESS ironed out and get it running I'll probably convert it to Premix just to be safe.

Thanks,

 

[kustomkarl]

I would be more set to just flow test the oil pump and save the expense of premix and use the conveniences of the injector.

Karl

 

[97SPX]

Once I get the DESS sorted out (another issue you're helping me with, thanks!) I need to get it running good and go over everything with a fine tooth comb first. I'm not in to hard-core racing or modifying this one. My goal is to maintain a highly reliable ride to tool the kids around the lake on, do as much of the work myself as possible and most important, keep the budget as low as possible!!

I though converting to premix might aid the reliability in the long run. I see conflicting advice on whether this is a good idea or not.

Thanks again.

 

[kustomkarl]

My own personal opinion with 30 years in the water craft field...keep the injector...everyone here has different backgrounds and experiences.

Karl

 

[kmack]

FWIW, coming from a 2-stroke motorcycle background, deleting the injector system (at least on motorcycles) means you have to re-jet the carbs. The addition of oil in the fuel stream going through the carb jets actually lessens the amount of fuel. What happens is you end up running the engine lean.

On my old Yamaha RD's, I always tried to keep the injector systems. When the pumps failed or were suspect, I always had to go to larger jets to compensate for the additional oil.

 

[robin savell lloyd]

Does any one know why the # seller of remanufactured seadoo engines addvices to pre mix your fuel when you buy a engine from them? I have a few ideas. Lets hear yours. :cheers: