Polaris Jet Ski Engine Running Issue

AC2717 · 08-13-2012, 08:50 AM

My Neighbor has a 1997 Polaris 780 SLT jetski.
They were riding it yesterday morning when all of a sudden it stalled out, it restarted back up but would not go past a certain speed even at full throttle.
and would not stay on idle. Have not had problems like this before on the machine ever.

I took a look at it and it seems like the fuel might be bad. They get their gas from a street gas station and did not stablize it. it gas was in the gas can about a week, but who knows how long at the gas station and then with all the humidity over the past week and a half....By the way they just filled it in the same morning before heading out it was about a quarter full.

So anyways, we changed the plugs, dropped some marine stabilizer in the tank, and a bottle of dry gas. Still wont stay idle, but got litteraly a scooch more power out of the machine. Also Oil is good as well.

My next step is to drain the whole tank and put new gas in there, change the plugs again and hopefully that will solve the problem??? ON a side note when I pulled the plugs and sniffed them they barely had a scent of fuel to them and when we dry fired the engine to check fuel pump there was fuel but barely had the gas smell to it

Only other thing I was thinking about is I did not know and could not find out if the machine had one of those speed switches on it that limited the speed or is it too old. Does anyone know??

Anyone have knowledge on this machine or type of problem?

08-13-2012, 08:50 AM	#1
AC2717 Senior Member Join Date: Apr 2007 Location: Maynard, MA & Paugus Bay Posts: 2,521 Thanks: 747 Thanked 344 Times in 257 Posts	Polaris Jet Ski Engine Running Issue My Neighbor has a 1997 Polaris 780 SLT jetski. They were riding it yesterday morning when all of a sudden it stalled out, it restarted back up but would not go past a certain speed even at full throttle. and would not stay on idle. Have not had problems like this before on the machine ever. I took a look at it and it seems like the fuel might be bad. They get their gas from a street gas station and did not stablize it. it gas was in the gas can about a week, but who knows how long at the gas station and then with all the humidity over the past week and a half....By the way they just filled it in the same morning before heading out it was about a quarter full. So anyways, we changed the plugs, dropped some marine stabilizer in the tank, and a bottle of dry gas. Still wont stay idle, but got litteraly a scooch more power out of the machine. Also Oil is good as well. My next step is to drain the whole tank and put new gas in there, change the plugs again and hopefully that will solve the problem??? ON a side note when I pulled the plugs and sniffed them they barely had a scent of fuel to them and when we dry fired the engine to check fuel pump there was fuel but barely had the gas smell to it Only other thing I was thinking about is I did not know and could not find out if the machine had one of those speed switches on it that limited the speed or is it too old. Does anyone know?? Anyone have knowledge on this machine or type of problem? __________________ Capt. of the "No Worries"