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.

 

[FSH 210 Sport]

How are you making out with the bolt extraction?

 

[Neutron]

What broke? The bolt that screws into the mount? If so just replaced the mount.
They are cheap, you can get a set of four for cheap money

 

[madtom]

How are you making out with the bolt extraction?

FSH,

Today, I finally managed to get a few uninterrupted hours on the repair. The limited access has made it impossible to pull the engine, so I'm working within the constraints presented by the situation—just dealing the cards I was dealt!

I'm using diamond-tipped granite bits at a conservative 600 rpm, which means the process is naturally going to take some time. My plan is to carefully attempt to extract what remains in the threads. However, if I end up stripping the plate entirely, I believe it would be more efficient to replace it with a new stainless steel helicoil.

For reference, I’ve attached a picture of the backside of the intermediate bearing—the very source of today's challenge.


Tom

 

[madtom]

What broke? The bolt that screws into the mount? If so just replaced the mount.
They are cheap, you can get a set of four for cheap money

One of the mount bolts that go into the hull

 

[Neutron]

One of the mount bolts that go into the hull

Oh, that sucks.
What will possibly happen is the nut that is set in the stringer will spin free. Had this happen a few times

 

[madtom]

So my diamond drill bit idea was successful while trying to remove what was left of a stubborn bolt. The approach proved successful, albeit with a few challenges along the way. In the process, I ended up using roughly eight 1/4-inch bits(thank you Amazon lol). The key was to go slow—taking about two hours to drill down far enough while regularly rinsing out the accumulated steel filings from the bit.

The primary goal was to drill down the center of the bolt—or as close as possible—ensuring that the bit stayed within the bounds of the bolt itself in for about one inch of depth. Once I achieved that, I switched to a left-hand 1/4-inch bit from an HF extractor kit. This allowed me to drill thru the rest of the bolt

After the initial drilling, I repurposed the diamond bit as a grinder to remove the remaining material from the bolt, up to the threads. To ensure accuracy, I threaded one of the middle bolts halfway in; this served as a gauge for the hole I had drilled. I then used a 19/64-inch left-hand bit from the HF kit to measure the diameter. The bolt hole ended up being approximately 7.4 mm, which was just sufficient to start off with an 8 mm tap. This precise outcome ultimately saved me from having to resort to the more complicated helicoil route.

I just hope that whatever is left of the bolt eventually makes it's way back to the area under the cleanout port so I can get it out . Stuff just rattling away makes me OCD. I still occasionally pull out a ziptie clipping that comes out thru the drain plug..... from when the factory put it together.... in 2018 .

This process not only demonstrated the effectiveness of the diamond drill bit method but also confirmed that with patience and careful control over the drilling and grinding actions, one can achieve a clean rethread even in challenging conditions.

 

[Neutron]

So my diamond drill bit idea was successful while trying to remove what was left of a stubborn bolt. The approach proved successful, albeit with a few challenges along the way. In the process, I ended up using roughly eight 1/4-inch bits(thank you Amazon lol). The key was to go slow—taking about two hours to drill down far enough while regularly rinsing out the accumulated steel filings from the bit.

The primary goal was to drill down the center of the bolt—or as close as possible—ensuring that the bit stayed within the bounds of the bolt itself in for about one inch of depth. Once I achieved that, I switched to a left-hand 1/4-inch bit from an HF extractor kit. This allowed me to drill thru the rest of the bolt


After the initial drilling, I repurposed the diamond bit as a grinder to remove the remaining material from the bolt, up to the threads. To ensure accuracy, I threaded one of the middle bolts halfway in; this served as a gauge for the hole I had drilled. I then used a 19/64-inch left-hand bit from the HF kit to measure the diameter. The bolt hole ended up being approximately 7.4 mm, which was just sufficient to start off with an 8 mm tap. This precise outcome ultimately saved me from having to resort to the more complicated helicoil route.

This process not only demonstrated the effectiveness of the diamond drill bit method but also confirmed that with patience and careful control over the drilling and grinding actions, one can achieve a clean rethread even in challenging conditions.

Nice work. Patience pays sometimes

 

[FSH 210 Sport]

So my diamond drill bit idea was successful while trying to remove what was left of a stubborn bolt. The approach proved successful, albeit with a few challenges along the way. In the process, I ended up using roughly eight 1/4-inch bits(thank you Amazon lol). The key was to go slow—taking about two hours to drill down far enough while regularly rinsing out the accumulated steel filings from the bit.

The primary goal was to drill down the center of the bolt—or as close as possible—ensuring that the bit stayed within the bounds of the bolt itself in for about one inch of depth. Once I achieved that, I switched to a left-hand 1/4-inch bit from an HF extractor kit. This allowed me to drill thru the rest of the bolt

After the initial drilling, I repurposed the diamond bit as a grinder to remove the remaining material from the bolt, up to the threads. To ensure accuracy, I threaded one of the middle bolts halfway in; this served as a gauge for the hole I had drilled. I then used a 19/64-inch left-hand bit from the HF kit to measure the diameter. The bolt hole ended up being approximately 7.4 mm, which was just sufficient to start off with an 8 mm tap. This precise outcome ultimately saved me from having to resort to the more complicated helicoil route.

I just hope that whatever is left of the bolt eventually makes it's way back to the area under the cleanout port so I can get it out . Stuff just rattling away makes me OCD. I still occasionally pull out a ziptie clipping that comes out thru the drain plug..... from when the factory put it together.... in 2018 .

This process not only demonstrated the effectiveness of the diamond drill bit method but also confirmed that with patience and careful control over the drilling and grinding actions, one can achieve a clean rethread even in challenging conditions.

Congratulations !!!

That was a long hard battle in what I’m sure was less than a comfortable position! Well done!

 

[madtom]

The lack of drama continues. The second intermediate bearing replacement was uneventful. I assembled the new bearing unit and confirmed that when grease is added through the fitting, it flows out at the rear around the shaft. Judging by the grooves machined into the housing, it appears that all the grease is directed toward the rear seals, and I’m not even sure if any reaches the bearing in the middle. I packed that puppy well before assembly so it is good to go. I reused the alignment pins from the old housing.


I plan to disassemble the old bearing assemblies later to assess their condition.

I removed the four motor mount bolts and the exhaust clamps before sliding the engine forward. No broken bolts this time only broke a 3/8 universal joint while removing back right mount. All new bolts for reassembly so timewise much easier to do. Difference is it requires more manhandling of the engine to remove shims and reinstall them after the new bolts were started. When i did the other engine more bolts to remove but just slide the engine around vs rocking this one to get the mounts to line up. Some of the shims between the mounts and the engine did not fall off completely, so I took photos of each mount prior to disassembly to record the number of shims at each corner—two shims on each rear mount and one on the front mounts. Once I pulled them out and laid them out in the correct location for each corner so I wouldn't forget their location. Apparently Yamaha makes them in different thicknesses so you don't want to mix them up.

Finally, before reinstall, I scrubbed all the sand and grit from the exhaust and the mounting surface of the intermediate bearing using dish soap and a plastic brush and using a pick under the exhaust rubber connector to remove all the hard stuff. Ended up hosing all the crap out of the engine compartment after I was done.

 

[FSH 210 Sport]

The lack of drama continues. The second intermediate bearing replacement was uneventful. I assembled the new bearing unit and confirmed that when grease is added through the fitting, it flows out at the rear around the shaft. Judging by the grooves machined into the housing, it appears that all the grease is directed toward the rear seals, and I’m not even sure if any reaches the bearing in the middle. I packed that puppy well before assembly so it is good to go. I reused the alignment pins from the old housing.
View attachment 234828

I plan to disassemble the old bearing assemblies later to assess their condition.

I removed the four motor mount bolts and the exhaust clamps before sliding the engine forward. No broken bolts this time only broke a 3/8 universal joint while removing back right mount. All new bolts for reassembly so I'm much easier to do but more manhandling of the engine to remove shims and reinstall them after the new bolts were started. Some of the shims between the mounts and the engine did not fall off completely, so I took photos of each mount prior to disassembly to record the number of shims at each corner—two shims on each rear mount and one on the front mounts. pulled them out and laid them out in the correct location for each corner so i wouldn't forget their location. Apparently Yamaha makes then in different thicknesses so you don't want to mix them up.

Finally, before reinstall, I scrubbed all the sand and grit from the exhaust and the mounting surface of the intermediate bearing using dish soap and a plastic brush and using a pick under the exhaust rubber connector to remove all the hard stuff. Ended up hosing all the crap out of the engine compartment after I was done.View attachment 234830

Did you add that temp sending unit?
How were the rubber Cush drives in the love joy drives?

 

[madtom]

Did you add that temp sending unit?
How were the rubber Cush drives in the love joy drives?

Added those temp units last year. Trailtech 22mm units..... Cut the hose at the thermostat for each, inserted sensor assy and ran wiring up to helm...self powered so no extra wiring. Engine Overheating Warning - Cleanout Plug Issue?

Rubber was starting to separate in port engine assy.... I haven't got Starboard apart yet. they were definitely cruddy on the backside from all the time setting in salt water with PO. When I pulled anodes from engine two years ago it was only a little ring around the bolt left lol. Saltwater has to be rinsed after every use and i would never just leave any jetboat just docked for days in the water like that. Freshwater different story.

Only 145 hours or so but PO literally put it in the water each weekend and pulled it out on Monday as he lived on the water....so untold hours just sitting in salt water/brackish. Port was making roaring noise after an all day cruise up to DC last year so it had to get done. Grease had rust in it so it was time. Glad this is done. pumps got rebuilt after the roaring noise because I wanted it to be the easy problem to fix...but i was wrong lol.

 

[FSH 210 Sport]

Right on…. You’ve done a bang up job bringing this boat back from neglect. These are great little boats, very versatile

Thanks for the information about the rubber Cush drives..

How were the pumps when you pulled them apart?

I just turned 600 hours on my engines the other day.. bout time for another valve lash check, and I’ll probably have the mechanic check those Cush drives while he is at it.

Also really appreciate the information on greasing them with a grease gun. Basically, if you have a little bit of finesse, you add grease until you feel the gun’s resistance slightly increase then stop, and any excess will push out around the shaft?

 

[madtom]

Follow-up. After reading thru the oil level discussion I double checked mine to make sure it was not impacting my RPMs. Both were right under the 3/4 mark after following the instructions. Today was a nice day to get out. Potomac was like glass today and not really any waves or wind. I was able to hit 8k on both engines 42-3 GPS speed, 46 on the Yamaha dreamo meter. Old bearings were pulling the RPMs down a little as I was never able to do that in the past. It was like 7.2 and 7.5 on the RPMs last year...... and no more roaring noise now. Wife even noticed it was quieter on the trip out. She usually ignores me after the first sentence of what I am working on and why it is critical to get it right. lol. She usually makes a joke from the movie " My Cousin Vinny" "Does it have posi-traction"

 

[FSH 210 Sport]

Follow-up. After reading thru the oil level discussion I double checked mine to make sure it was not impacting my RPMs. Both were right under the 3/4 mark after following the instructions. Today was a nice day to get out. Potomac was like glass today and not really any waves or wind. I was able to hit 8k on both engines 42-3 GPS speed, 46 on the Yamaha dreamo meter. Old bearings were pulling the RPMs down a little as I was never able to do that in the past. It was like 7.2 and 7.5 on the RPMs last year...... and no more roaring noise now. Wife even noticed it was quieter on the trip out. She usually ignores me after the first sentence of what I am working on and why it is critical to get it right. lol. She usually makes a joke from the movie " My Cousin Vinny" "Does it have posi-traction"

That’s awesome to hear!!! I’m a bit envious.. I’ve never gotten my boat to go that fast, the lowest elevation I’ve ever had it at was 600’, I see you’re at like 50 so that makes sense.

I’m glad to see that all that freaking hard work paid off and you’re back at it!


Damn that girl was hot in that movie!

 

[Jerlane]

I hope I never have to do this, but I'm curious how you move the engine out of the way? Do you happen to have a shop with a lift? Doesn't sound like something your average DIYer could do.

 

[FSH 210 Sport]

I hope I never have to do this, but I'm curious how you move the engine out of the way? Do you happen to have a shop with a lift? Doesn't sound like something your average DIYer could do.

I’m pretty sure you just muscle it forward…. From what I’ve seen posted there is enough room to slide it forward on the mounts

 

[madtom]

I’m pretty sure you just muscle it forward…. From what I’ve seen posted there is enough room to slide it forward on the mounts

TR1s only weigh 160lbs... slide it forward 2 inches with pump already pulled so you can remove intermediate assembly. Hoses and wiring have enough slack built in. Other big help was platform plank over engines. Not pretty but it works. Lying on that allows you to use both arms and hands as you work vs using one arm for support.