96 Raider Air in the fuel filter???

[tigerorion]

Yes, the same bogging Raider. AKA (Zoolander) can't turn Left, ski. After checking everything and I mean alot of stuff:

Pulled engine, replaced lower seal
Carb inspection twice
lines blown out
new fuel filter
bypassed reserve switch
engine compression 130 and holding on all three
new fuel
rebuilt fuel pump
took off Riva Air filters, replaced with orig Yamaha
restricted return line to gas tank

This ski still blogs out when it jumps around, worse on the left turn, unless you keep and let it over 3/4 throttle n the turn.
When I decided to bypass the reserve on / off switch, I kept the engine hood open, to see if it was pulling fuel into the filter before I took it out on the river and might have realized I had hooked it up wrong. I noticed that the filter filled up with 3/4 air. The only other thing different about this ski is that the owner before me put a primer system in place of the choke. Could this primer be letting air into the system?

[Technical Support]

Re: 96 Raider Air in the fuel filter???

You could be sucking air any place between the sending unit up to the carb, go back and check everything. You can even bypass everything and run a fuel line from the tank directly to the carb, see how that works then go back and find the problem.

[John Kubiak]

Re: 96 Raider Air in the fuel filter???

The "Left Turn Syndrome"
You will find in all instances that your watercraft will turn more easily to the right than to the left. The reasons are basically simple. First, engine torque constantly places pressure on the hull to turn right. If your engine's performance is marginal, you can notice a dramatic falloff in power in a hard turn. This power falloff can't always be blamed on the engine, being over-propped can also cause the engine to slow enough to fall off its power peak. An engine with a peaky power curve is especially susceptible to a very dramatic power loss in a hard left turn. Most recently, with the increase of Sport and Runabout racing, there has been a marked improvement in hull design with a dramatic increase in "G" forces encountered while turning: over 2.5 G's. In some instances such a hard left turn can cause momentary loss of power due to fuel starvation in the carbs. Jetting changes cannot correct this situation, the best solution is to rotate the mounting of the carbs 90 deg, so that their throttle shafts are perpendicular to the crankshaft axis rather that parallel. To date, this solution to the problem has been most successful. This becomes even worse when the fuel diaphragms are facing away from the engine, as the g-forces physically forces the liquid fuel away from the fuel metering jets. Sometimes the fuel lines are routed under the steering cable, and become pinched closed in hard left turns...this can be addressed by re-routing the fuel lines to a better location.