Custom/Hybrid bob gen 2 pump problem??

[jstuntin]

I have a bob gen 2 setup with a kawi 750 motor,driveshaft and pump. since my driveshaft like the yamaha setup is not all one piece with the pump i cant really shim it. I have the engine in the hull non shimmed and the rear pump shimmed down in the rear. So now heres the problem. The first pump shaft spun the impeller off ruining the shaft and impeller againt pump walls. Rebuilt pump shaft and bearings, new impeller installed. Rode for about 1 hour, impeller was coming loose again and hitting pump walls. Took impeller out of the pump and put lock tight on it to stop from loosing up. Then rode yesterday for about 2 hours, sheared pump shaft right in half?? how do i shim this,solve this or has anyone else had this problem??? need help

 

[rubbertoe]

i ran into an issue when i switched to a mag pump with my driveshaft needing to be shimmed at the impeller nose, you might be experiencing the same problem ? if your driveline is not long enough you might not have proper engagement at the drive couplers causing enough vibration to cause the problems you are describing ..idk .just something to consider .on the Bob the couplers are tucked back in the hull so i would pull off the head pipe and make sure you have proper engagment at the drive couplers ,if you don't, space the drive shaft at the nose of the prop with a small piece of waterline to act as a spacer .remember you still need a reasonable amount of spline engagement at the prop(i wouldn't space much more than 1/2" , make sure everything is lined up straight at the drive couplers all the way around (equal reveal in spacing all the way around ,and couplers are lining up titties straight with each other ) loosen the bolts at the driveshaft bearing housing if necessary to line everything up then re tighten . hope this helps you .

 

[wanderer1]

Have you called The Ski Clinic? Maybe they have the answer. Rubbertoe gave some good advice also

 

[jstuntin]

sweet thanks for the help. I talked to dave and ski clinic, the just tighten the shaft housing down during shipping so its doesnt rattle around. I guess i have to bolt everything together with the housing loose so it can adjust itself and then when everything is straight and correct tighten it right up so there is no binding. Gonna give it a shot, if not back to the drawing board. Thanks homies

 

[DK-Freestyle]

sweet thanks for the help. I talked to dave and ski clinic, the just tighten the shaft housing down during shipping so its doesnt rattle around. I guess i have to bolt everything together with the housing loose so it can adjust itself and then when everything is straight and correct tighten it right up so there is no binding. Gonna give it a shot, if not back to the drawing board. Thanks homies

Yes, that sounds correct.
Also, if you have any future questions, do not hesitate to give us a call or shoot us an email, we'd be glad to help you out!

(925) 706-2858
thebobhull@theskiclinic.com

 

[wanderer1]

There you go, call the dudes that make/build them and you are square. Good luck.