New to forum, but not to skis. I recently purchased a 99 GTX limited. 135 psi on each cylinder. 160+ hours on ski. test ride on ski made 6800 rpm with worn out wear ring. all stock ski with oil injection still hooked up.
After initial test ride and purchase, I ran ski threw one full tank of fuel as I purchased it. ski would hit 6800 to 7000 rpm, but would often fall to 5800. it fouled out one plug, replaced plug and ran at 5800 max for majority of tank.
I then rebuilt carbs. converted to premix and installed new wear ring. All new fuel lines were replaced. all clamps on fuel system, (minus accelerator pump lines). removed gas tank and cleaned. rebuilt fuel selector switch (new o rings). ski is 100% stock. set carbs to 1.5 low and 0 high. jets are 162.5 and 70. Carbs got all new parts with the exception of needles, needle seats, and the springs associated to the needle sets. I also did not replace the small plastic tab that is screwed onto the valve assembly (item number 40 in the parts catalog).
Ski will hit 5600 rpm from a dead stop and not go past 5600rpm with factory air intake attached. Without air intake attached, it will hit 6000 at approximately 3/4 throttle and after 3/4 throttle to WOT rpm will decrease a couple hundred rpm. At random times, ski will hit 6800+ without air intake, but it only happened for about 5 minutes and then went back to around 6000. Air fuel mixture is good at WOT (golden brown spark plugs) after shutting ski off at WOT. idles fine.
I have double checked the fuel system for leaks. I have test both my Rave valves as well as my water regulator. All move freely by means of air pressure (my mouth) with the springs removed. both rave valves and water regulator are adjusted to be fully turned clockwise. skis runs at 92 degrees max.
I feel it is a fuel issue, but looking for insight. Tomorrow I will be installed a inline primer bulb that are commonly used on outboard boat motors to see if there is a lack of fuel pressure in the ski. I will simply pump the bulb while running to see if the rpm increases past 6000.
One mentionable thing is I can adjust the high speed screws on the carb OUT at idle and the idle will increase. I have found that the ski performs better with the high speed screws out around 360 degrees ( 1 full turn). This makes me think it is a fuel problem aka lack of fuel pressure
carbs are opening fully. When the ski was hitting 6800 RPM without air intake installed, it would slowly climb to 6800 from 6000. speedo indicated around 60mph at 6800 rpm.
My one question are the fuel pump one way valves ( little round plastic circles about size of nickel) directional? I mean can they be put in backwards? I did not see any concave or convex shape that would indicate they are "directional".
any input will be appreciated.
After initial test ride and purchase, I ran ski threw one full tank of fuel as I purchased it. ski would hit 6800 to 7000 rpm, but would often fall to 5800. it fouled out one plug, replaced plug and ran at 5800 max for majority of tank.
I then rebuilt carbs. converted to premix and installed new wear ring. All new fuel lines were replaced. all clamps on fuel system, (minus accelerator pump lines). removed gas tank and cleaned. rebuilt fuel selector switch (new o rings). ski is 100% stock. set carbs to 1.5 low and 0 high. jets are 162.5 and 70. Carbs got all new parts with the exception of needles, needle seats, and the springs associated to the needle sets. I also did not replace the small plastic tab that is screwed onto the valve assembly (item number 40 in the parts catalog).
Ski will hit 5600 rpm from a dead stop and not go past 5600rpm with factory air intake attached. Without air intake attached, it will hit 6000 at approximately 3/4 throttle and after 3/4 throttle to WOT rpm will decrease a couple hundred rpm. At random times, ski will hit 6800+ without air intake, but it only happened for about 5 minutes and then went back to around 6000. Air fuel mixture is good at WOT (golden brown spark plugs) after shutting ski off at WOT. idles fine.
I have double checked the fuel system for leaks. I have test both my Rave valves as well as my water regulator. All move freely by means of air pressure (my mouth) with the springs removed. both rave valves and water regulator are adjusted to be fully turned clockwise. skis runs at 92 degrees max.
I feel it is a fuel issue, but looking for insight. Tomorrow I will be installed a inline primer bulb that are commonly used on outboard boat motors to see if there is a lack of fuel pressure in the ski. I will simply pump the bulb while running to see if the rpm increases past 6000.
One mentionable thing is I can adjust the high speed screws on the carb OUT at idle and the idle will increase. I have found that the ski performs better with the high speed screws out around 360 degrees ( 1 full turn). This makes me think it is a fuel problem aka lack of fuel pressure
carbs are opening fully. When the ski was hitting 6800 RPM without air intake installed, it would slowly climb to 6800 from 6000. speedo indicated around 60mph at 6800 rpm.
My one question are the fuel pump one way valves ( little round plastic circles about size of nickel) directional? I mean can they be put in backwards? I did not see any concave or convex shape that would indicate they are "directional".
any input will be appreciated.
