Yamaha Jet Pump Disassembly - From Grant Browne YouTube

[Bruce]

J

Very helpful as I believe the bearings have seized n starboard up nd stopping rhe engin spinning. Feel more confidant to pull the pum off now

Thanks
Mike
South Wales
UK

Have a look at this thread as well https://jetboaters.net/threads/chan...-and-switching-to-oil-bath-lubrication.10155/

 

[skyrme802]

Have a look at this thread as well https://jetboaters.net/threads/chan...-and-switching-to-oil-bath-lubrication.10155/

Thanks Bruce very useful post i will pull the pump apart first to check first and then see if I can get the rebuild kits in the UK cheers
Mike

 

[Bruce]

Thanks Bruce very useful post i will pull the pump apart first to check first and then see if I can get the rebuild kits in the UK cheers
Mike

The pump bearings and seals are also used on skis.

 

[skyrme802]

That is good to know as there is a Yamaha Jet Ski dealer close to me, Not many Jet Boats in the UK bit plenty of Ski's.
Thanks again Bruce, cheers
Mike

 

[Julian]

As for what Yamaha officially calls for when assembling the pump, this is their Gasket Maker:


Now I've seen many people who've pulled pumps and re-assembled without using this, and all the videos at the top of this thread also make no mention of Gasket Maker (they are dealer videos). So the need for this is limited IMHO.

 

[Cambo]

Has anyone else snapped a bolt I barely put any force on it and it sheared off. They are soft and easy to drill and tap for the install of a new bolt. The boat is in salt water so it most likely gauled up the threads. The previous owner moored it for a season both wear rings needed replacement on a 2017, didn't get three years out of them. My previous 2005 still had original pump liners when sold in 2019 and I had removed all the bolts with no issues. Salt water destroys things if you leave the boat moored or docked.

 

[granpachuck]

Has anyone else snapped a bolt I barely put any force on it and it sheared off. They are soft and easy to drill and tap for the install of a new bolt. The boat is in salt water so it most likely gauled up the threads. The previous owner moored it for a season both wear rings needed replacement on a 2017, didn't get three years out of them. My previous 2005 still had original pump liners when sold in 2019 and I had removed all the bolts with no issues. Salt water destroys things if you leave the boat moored or docked.

This is what frightened me; I have no experience drilling and tapping new threads, and not in hurry to earn that merit badge. Pulled them out today, and all 8 of them were very snug. None broke thankfully.

 

[drewkaree]

This is what frightened me; I have no experience drilling and tapping new threads, and not in hurry to earn that merit badge. Pulled them out today, and all 8 of them were very snug. None broke thankfully.

Now that you're past that part, maybe consider a cheap tap/die set from Harbor Freight, to practice and get comfortable with the process. $10-15 should get you something (although not ideal), and it's better to practice when you're not stressed over something.

 

[granpachuck]

Now that you're past that part, maybe consider a cheap tap/die set from Harbor Freight, to practice and get comfortable with the process. $10-15 should get you something (although not ideal), and it's better to practice when you're not stressed over something.

That is good advice. I am not too old to learn a new skill, and gives me an excuse to buy some more tools.

 

[Cambo]

The biggest mistake you can make is forcing the tap and snapping it, re drilling then becomes difficult due to the hardened steel of the tap being lodged in place. I have taken off about 8 pumps and only once it snapped

 

[granpachuck]

The biggest mistake you can make is forcing the tap and snapping it, re drilling then becomes difficult due to the hardened steel of the tap being lodged in place. I have taken off about 8 pumps and only once it snapped

That ratio does not give me piece of mind at all... Is it crazy to just replace the bolts every time or other time you pull them ? I doubt they get stronger with age, weather, torque. I have no idea of the cost of a set of 8, but using them until they snap maybe isn't in my best interest.