1998 120xr sportjet pump and drive

[shub shub 123]

I have a 1998 tracker 18 pro with a 120 xr sportjet.Years ago I found the previous owner had cracked the grate and the turbine housing .I half ass welded and JB welded it together twice in 15 years.The second time I sucked a rope and had to redue the repair.2 years ago I took it out on the way in with 3 adults and a small child it wouldn't get on plane it was plowing water.So it sat for covid.So I rebuilt the carbs and drain the tank.It starts fine. I have 2 issues .I have a real bad stall stumble off idle that can be a non issue if you throttle slow past the stumble area .I seemed to get on plane with me and my daughter that weighs 100# .The second issue is more of a issue. When I open it up it seems like it cavitates almost like obstruction in The grate. But gets up and has ample speed.But next i had my caught sit up front and this time it took longer to get on plane and it seemed to struggle. So I'm thinking the housing is cavitating and it might be time to find some housing parts. But my question s are , could the throttle issues be my route issue? And what to check. ? Is there any way to be sure it's is the jet pump ? Does any one know where i can find a used jet drive unit? Does anyone know what other boats or jet skies use this same jet drive?

 

[QBhoy]

Have you checked the impeller prop to wear ring clearance ? Is the pump intake all well sealed
The other issue is carb related, most likely

 

[shub shub 123]

Thanks ,no i don't know how to do that .I ordered a manual,maybe it will help. I may be found carb kits.they were listed as tilston c series i think. It looked close so I took a chance