KingCold
Jet Boat Lover
- Messages
- 40
- Reaction score
- 12
- Points
- 67
- Location
- Mount Vernon, VA
- Boat Make
- Yamaha
- Year
- 2017
- Boat Model
- FSH
- Boat Length
- 19
Pull engine.
Note: You can remove the coupler with the engine on the ground, or suspended on a chain. I did one each way. Just as easy each way. I’d go suspended (mine was on a gantry crane).
Use a large allen socket to remove the retaining bolt on the end of the drive coupler. I used a t-60 torx socket that was sloppy, but worked. This is a left-hand thread bolt and easy to remove. So you should be a righty-loosey - turn it clockwise.
Remove rear cylinder coil pack and spark plug.
Put a really long screw driver or other slim lengthy thing in the spark plug hole.
Rotate the the crank clockwise - using a pry bar / breaker bar through the drive coupler teeth. Rotate it until the screw driver pops up as far as it will go and then drops back down lower into the cylinder.
Once the screw driver drops away from top dead center (all the way out of the hole) and the piston is down, remove the screw driver and feed 3/8” braided poly rope into the spark plug hole.
Note: I had to use the screwdriver to push the rope at the edge of the spark plug hole into the cylinder head.
Now that the cylinder has a bunch of rope in it, use the pry bar to rotate the crank counter clockwise until the piston comes up, compresses the rope, and stops. The rope keeps the piston from hitting top dead center and rotating back down. Yay! Crank is now stationary.
Use a heat gun to heat the drive coupler and loosen the thread locker. Heat goes into the hole on the end of the crank you removed the retaining bolt from - this puts the heat directly onto the threads of the drive coupler and crank.
Note: Heat gun doesn’t take long. I would not recommend a torch.
Once the drive coupler is hot on the outside edge, like hard to touch hot, turn off the heat and use a long breaker bar through the teeth of the drive coupler to turn the drive coupler counter clockwise. Both of mine went pretty easy and did not require massive force. Once you get it going with the pry bar, use a rag to spin the hot coupler off and clean the threads.
Note: I reinstalled a different coupler and used it to rotate the crank clockwise (to release the rope in the cylinder). You could likely use a protective rag and water pump pliers on the crank too - it just has to bump a bit clockwise to release the rope).
Note: You can remove the coupler with the engine on the ground, or suspended on a chain. I did one each way. Just as easy each way. I’d go suspended (mine was on a gantry crane).
Use a large allen socket to remove the retaining bolt on the end of the drive coupler. I used a t-60 torx socket that was sloppy, but worked. This is a left-hand thread bolt and easy to remove. So you should be a righty-loosey - turn it clockwise.
Remove rear cylinder coil pack and spark plug.
Put a really long screw driver or other slim lengthy thing in the spark plug hole.
Rotate the the crank clockwise - using a pry bar / breaker bar through the drive coupler teeth. Rotate it until the screw driver pops up as far as it will go and then drops back down lower into the cylinder.
Once the screw driver drops away from top dead center (all the way out of the hole) and the piston is down, remove the screw driver and feed 3/8” braided poly rope into the spark plug hole.
Note: I had to use the screwdriver to push the rope at the edge of the spark plug hole into the cylinder head.
Now that the cylinder has a bunch of rope in it, use the pry bar to rotate the crank counter clockwise until the piston comes up, compresses the rope, and stops. The rope keeps the piston from hitting top dead center and rotating back down. Yay! Crank is now stationary.
Use a heat gun to heat the drive coupler and loosen the thread locker. Heat goes into the hole on the end of the crank you removed the retaining bolt from - this puts the heat directly onto the threads of the drive coupler and crank.
Note: Heat gun doesn’t take long. I would not recommend a torch.
Once the drive coupler is hot on the outside edge, like hard to touch hot, turn off the heat and use a long breaker bar through the teeth of the drive coupler to turn the drive coupler counter clockwise. Both of mine went pretty easy and did not require massive force. Once you get it going with the pry bar, use a rag to spin the hot coupler off and clean the threads.
Note: I reinstalled a different coupler and used it to rotate the crank clockwise (to release the rope in the cylinder). You could likely use a protective rag and water pump pliers on the crank too - it just has to bump a bit clockwise to release the rope).
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