intermediate bearing replacement info.

[anmut]

So... is 2-3 pumps per season from the zirt fitting connected to the hose still correct?

 

[madtom]

Hi,

Current 2019 Yamaha FSH 210 owner and am currently replacing the intermediate bearings. I have about 145 hours on the boat. the previous owner used it in brackish water (Florida), docked on weekends, and then put back on the trailer on Monday mornings. Last year, the left engine drivetrain developed a persistent grinding/roaring noise, and its RPM was 400–500 lower than the right engine. I rebuilt both pumps, but the noise remained. Although there was no water leak, I noticed that the grease on the left side had a rusted, water-intruded appearance and was starting to drip from the front of the housing. Clearly, that bearing is worn out and has extra play.

I’ve received all the required parts from Boats.net and have rebuilt the bearing assemblies for both sides. Since replacing one is such a hassle, I decided to replace both at the same time rather than doing it piecemeal. The parts cost a bit more, but I’m confident that I’m getting genuine Yamaha components with authentic Japanese bearings instead of rebuilt ones from eBay. Interestingly, the same intermediate assembly is used in various models of Wave Runners and other jet boats from the past 20 years.

I added grease to the first bearing after assembly and when the pump got to where it felt full the extra grease was coming out on the back side of the seal around the intermediate shaft. Seal design and installation indicates it will keep water out but the grease will push past the seal lip. I also packed the bearings before putting the assemblies together.

I plan to post pictures of my progress as I move further along with the repairs.

Additionally, I added white 4200D sealant to the seams in the hull because the factory sealant around the pump shoe was deteriorating. I expect this will bring a slight performance boost once I finish reassembling everything.

While removing the engine mount bolts to lift the engine, I broke one of the bolts. The combination of saltwater, aluminum, and stainless steel creates a strong galvanic reaction—something I underestimated with my regular 3/8" ratchet. I ended up breaking the bolt, which now poses another challenge.

I also broke several drill bits while trying to start a pilot hole. I have now switched to a carbide-tipped/diamond bit (the type used for drilling granite), and I’m working slowly at a low speed of around 400–600 RPM to keep the bit cool. I’m hoping that the drilling will generate enough heat for the Kroil to penetrate the threads, making removal easier. Worst case, I might have to drill out the plate and install a Heli-Coil—a solution that’s eating into time I could be enjoying on the boat!

Has anyone else experienced a broken motor mount bolt? The bolt broke flush with the fiberglass, and I’m not keen on welding a nut on top. As mentioned, I’m slowly drilling to avoid complications.

I also learned that the Yamaha boat design features an aluminum plate embedded in the fiberglass where the motor mounts attach. This plate is pre-drilled and threaded for the motor mount bolts. Does anyone have a recommendation for an ideal anti-seize or thread locker when putting it back together?

Feel free to share your experiences or suggestions!

 

[FSH 210 Sport]

Hi,

Current 2019 Yamaha FSH 210 owner and am currently replacing the intermediate bearings. I have about 145 hours on the boat. the previous owner used it in brackish water (Florida), docked on weekends, and then put back on the trailer on Monday mornings. Last year, the left engine drivetrain developed a persistent grinding/roaring noise, and its RPM was 400–500 lower than the right engine. I rebuilt both pumps, but the noise remained. Although there was no water leak, I noticed that the grease on the left side had a rusted, water-intruded appearance and was starting to drip from the front of the housing. Clearly, that bearing is worn out and has extra play.

I’ve received all the required parts from Boats.net and have rebuilt the bearing assemblies for both sides. Since replacing one is such a hassle, I decided to replace both at the same time rather than doing it piecemeal. The parts cost a bit more, but I’m confident that I’m getting genuine Yamaha components with authentic Japanese bearings instead of rebuilt ones from eBay. Interestingly, the same intermediate assembly is used in various models of Wave Runners and other jet boats from the past 20 years.

I added grease to the first bearing after assembly and when the pump got to where it felt full the extra grease was coming out on the back side of the seal around the intermediate shaft. Seal design and installation indicates it will keep water out but the grease will push past the seal lip. I also packed the bearings before putting the assemblies together.

I plan to post pictures of my progress as I move further along with the repairs.

Additionally, I added white 4200D sealant to the seams in the hull because the factory sealant around the pump shoe was deteriorating. I expect this will bring a slight performance boost once I finish reassembling everything.

While removing the engine mount bolts to lift the engine, I broke one of the bolts. The combination of saltwater, aluminum, and stainless steel creates a strong galvanic reaction—something I underestimated with my regular 3/8" ratchet. I ended up breaking the bolt, which now poses another challenge.

I also broke several drill bits while trying to start a pilot hole. I have now switched to a carbide-tipped/diamond bit (the type used for drilling granite), and I’m working slowly at a low speed of around 400–600 RPM to keep the bit cool. I’m hoping that the drilling will generate enough heat for the Kroil to penetrate the threads, making removal easier. Worst case, I might have to drill out the plate and install a Heli-Coil—a solution that’s eating into time I could be enjoying on the boat!

Has anyone else experienced a broken motor mount bolt? The bolt broke flush with the fiberglass, and I’m not keen on welding a nut on top. As mentioned, I’m slowly drilling to avoid complications.

I also learned that the Yamaha boat design features an aluminum plate embedded in the fiberglass where the motor mounts attach. This plate is pre-drilled and threaded for the motor mount bolts. Does anyone have a recommendation for an ideal anti-seize or thread locker when putting it back together?

Feel free to share your experiences or suggestions!

As far as PM on the bolts is concerned my first thought is the white Loctite 572, it’s the same low yield thread sealant used on the large jet pump bolts that hold the pump assembly to the transom plate.

https://www.amazon.com/dp/B000O03DTQ?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1

That is such a drag that bolt broke off! Sounds like your slow going method is the best, I hope the bolt remnant will come out cleanly enough to re use the same hole, but if it doesn’t you’ve got plan be in the form of a heli coil to fix it.

Thanks for the info on the seal design and how some grease will push past. Kinda sounds like the previous owner did not grease the seals ?

Looking forward to your project pics.