[straw530]

My 72 300 olympique is giving me trouble. I rebuilt the carb (tillitson) put new upper end gaskets in, new fuel lines etc. The sled will start up and run good, I can ride it for 5 miles or so and then it will die, like its starving for gas. If I choke it a little it will run a little. If I then let it sit and cool off, I can ride it again for a few miles with the same result. I am wondering if I am losing prime because the motor is sucking air, or if something is wrong in the carb. Any ideas?

 

[skidoo 68]

you might want to change the needle and seat

 

[JGabriel]

I had the same problem wqith my 71 300. It turned that air was gettin into the fuel lines and it would eventually run out of gas unless you primed it or hit the choke. I replaced the lines and it works perfect now.

 

[DaytonaTurbo]

had the same problem with another 2 stroke(not a sled though). Turned out it had lost too much compression. When cool the piston/sleeve seal was good but as it heated up, clearance increased and it lost compression, and died until I let it cool down, so it contracted, sealed better and compression went back up until I ran it for a while longer.

 

[bwthor]

My 72 300 olympique is giving me trouble. I rebuilt the carb (tillitson) put new upper end gaskets in, new fuel lines etc. The sled will start up and run good, I can ride it for 5 miles or so and then it will die, like its starving for gas. If I choke it a little it will run a little. If I then let it sit and cool off, I can ride it again for a few miles with the same result. I am wondering if I am losing prime because the motor is sucking air, or if something is wrong in the carb. Any ideas?

[snapback]702956[/snapback]​

It sounds like it is running out of fuel, either because the fuel tank pickup or filter is plugged. Usually that would happen a little sooner. Is there a breather on the fuel tank? It is possible that it is sealed so well that as the fuel gets sucked out it creates a vacuum that eventually overcomes the sucking power of the carb. Good luck.

 

[blizzardboy]

[Just checked out the pictures of yourOly. Awsome job! It turned out really nice