View Full Version : Optimax 250 Not running

06-29-09, 07:38 AM
After a weekend of running excellent out on the water, i hit a standstill. I never usually run the fuel tank this low, but i ran it to about 1/4 tank. I was doin about 50 mph when it suddenly bogged down to about 3K RPM. I stopped to fill her up and it ran great for a couple of mins then bogged back down. I finally made it to a dock took the cover off the motor and the throttle body was completly black (oily, sooty). Apart from that the whole trip back to the dock while it was bogging, it was smoking a hell of alot. Does this have to do with the fuel? Do I use throttle body cleaner to clean the throttle body and that whole section?

I also noticed that the small air filter by the throttle body was completley black and dirty which it wasnt before.

Any advice on the situation. Ive been treating the gas with stabil ethanol formula, but I'm scared that the previously owner never treated it and it might have water at the bottom of the tank?

Sorry for the long post but I need to get back on the water!

06-29-09, 04:06 PM
No one on this topic?

07-02-09, 11:14 AM
I really need help can anyone help me out with this Optimax?

07-07-09, 07:49 AM
So after finally getting sometime to work on the engine I got her running rough but at least shes running. Put a new air compressor filter on it and removed the throttle body and thoroughly cleaned the body and the intake. It was horribly dirty but i left it looking brand new. While i was there i changed out the fuel/water separator and there was no water in the system thankfully. I will be changing out the plugs today to see if it stops running rough. At least it runs! If you guys have any suggestions, let me know

07-07-09, 09:05 PM
Sorry, I was away on holidays and did not see your thread. It is possible that you had some dirt or contaminants in the fuel, but I don't think I would bother using Stabil or any other chemical every tank unless the boat sits for long periods at a time, just stick to good clean fresh fuel.

Remember with a two-stroke anything you put in the fuel ends up lubricating the crankshaft. If everything is sooty and black definitely start with changing the plugs, two-strokes can be very sensitive to plug condition no matter what they look like.


07-08-09, 08:14 AM
Thank you man. I changed out the plugs last night and they were extremely sooty. Only last from february to now? SOmething seems odd. It is working excellently now though!