I purchased a 97 Seadoo Gti and installed a new wear ring & changed the pump oil. The pump bearings I suspected might need replacing. I had the Seadoo out on the water for 8 hours & it started seriously cavitating on takeoff. The new wear ring was worn far greater than it should for that little use. I suspected bad pump bearings again & ordered the parts for a full pump rebuild.
On disassembly the thrust bearing was being eaten next to the shaft. Pump shaft was worn by the front seal. pump bearings appeared fine. I pulled the pump & did the disassembly however a dealer did the reassembly (I don't have a press.) All new bearings, shaft, anti-rattle cone, Delrin wear ring. Skat Trak 16/21 swirl was installed by previous owner and is in brand new condition. Pump cone was pressure tested & BRP oil used. The first thing I noticed was how tight the impeller fit into the SBT Delrin wear ring. I couldn't turn it by hand. The dealer didn't say anything about this. I had to pull the plugs on the engine to get it to turn over but eventually the impeller seated & engine started great. I thought better for the impeller to fit too tight than too loose.
I took the Seadoo to the lake & WOW what a difference it tookoff & ran great. However after about 3 hours of running my wife came for a ride with me & I notices some cavitation. On full throttle launch its bouncing off the rev limiter. I came home and wear ring clearance is .018". Motor has never been out. Mounts seem like they are good condition since there is no play. Since the motor hasn't been out I wouldn't assume alignment problems. I also don't suspect a bent shaft since no obvious vibration. Wear ring wear appears even. What would cause the rapid wear on the ring & cavitation. Not a shallow water or debris issue. Could it be a bad grind on the Skat Trak 16/21? Nothing obvious to an non expert. Took off intake grate & no play in shaft. My suspicion is a bad grind on the Skat Trak 16/21
Here are pics of the pump shaft & bearing. Notice where the thrust bearing failed. All OEM original 1997.
The wear ring I put in prior to pump rebuild. Notice bad wear with only 8 hours on it. No rocks or debris damage. Impeller looks brand new.
On disassembly the thrust bearing was being eaten next to the shaft. Pump shaft was worn by the front seal. pump bearings appeared fine. I pulled the pump & did the disassembly however a dealer did the reassembly (I don't have a press.) All new bearings, shaft, anti-rattle cone, Delrin wear ring. Skat Trak 16/21 swirl was installed by previous owner and is in brand new condition. Pump cone was pressure tested & BRP oil used. The first thing I noticed was how tight the impeller fit into the SBT Delrin wear ring. I couldn't turn it by hand. The dealer didn't say anything about this. I had to pull the plugs on the engine to get it to turn over but eventually the impeller seated & engine started great. I thought better for the impeller to fit too tight than too loose.
I took the Seadoo to the lake & WOW what a difference it tookoff & ran great. However after about 3 hours of running my wife came for a ride with me & I notices some cavitation. On full throttle launch its bouncing off the rev limiter. I came home and wear ring clearance is .018". Motor has never been out. Mounts seem like they are good condition since there is no play. Since the motor hasn't been out I wouldn't assume alignment problems. I also don't suspect a bent shaft since no obvious vibration. Wear ring wear appears even. What would cause the rapid wear on the ring & cavitation. Not a shallow water or debris issue. Could it be a bad grind on the Skat Trak 16/21? Nothing obvious to an non expert. Took off intake grate & no play in shaft. My suspicion is a bad grind on the Skat Trak 16/21
Here are pics of the pump shaft & bearing. Notice where the thrust bearing failed. All OEM original 1997.
The wear ring I put in prior to pump rebuild. Notice bad wear with only 8 hours on it. No rocks or debris damage. Impeller looks brand new.
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