Need help with motor problem

[tjc45]

I have a 1999 150hp Evinrude Ficht. The motor has very low hours and has had all the updates. This motor has run like a champ until this past weekend. On the way out to do tube pulling duty the motor jumped like it hit something. In 18 feet of clean water, not the case. I stopped looked over the prop and lower end of the motor and all was good. I also surveyed the area for debris, nothing. Later in the day, after a couple hours of operation it did it again. It then did it several more times at different rpm settings. On the half hour trip back to the marina it did it once. At the marina at no wake speed it was doing it almost constantly. It'a millisecond jump where the motor vibrates and sends out a metallic sound. At speed the boat slows down. It feels similar to prop cavitation. I'm not sur if the noise is coming from the engine or the brackets. So what is this? The engine shifts flawlessly. Any help would be greatly appreciated.

 

[Walker]

Re: Need help with motor problem

Sounds like your forward clutch dog is skipping on the forward gear. Not good, Shift cable adjustment might cure it but I wouldn't run it except for maybe a short test after adjusting the shift cable. If it keeps doing it it will onlt cause more damage. Try disconnecting the shift cable at the motor and shifting into forward by hand and see if it still skips.

 

[tjc45]

Re: Need help with motor problem

Originally posted by Walker:<br /> Sounds like your forward clutch dog is skipping on the forward gear. Not good, Shift cable adjustment might cure it but I wouldn't run it except for maybe a short test after adjusting the shift cable. If it keeps doing it it will onlt cause more damage. Try disconnecting the shift cable at the motor and shifting into forward by hand and see if it still skips.

I'm mechanically challenged, damage to what? The clutch, the lower unit? Thanks

 

[Walker]

Re: Need help with motor problem

"clutch dog" is not really a ckutch at all, its just called that. It is a Metal ring that sits in your lower unit on the prop shaft between the forward and reverse gears. It has metal "dogs" on each end that mate up with corresponding dogs on the forward and reverse gears. . The clutch dogs and the dogs on the gears are machined at perfect right angles and have sharp square faces. When you shift gears the clutch dog is pushed via the Lower unit shift linkage either forward or backward to engage the gear that then turns the propshaft. If the faces of the dogs get rounded off then your gears start skipping as the dogs ,insteadof mating up perfectly, start jumping over each other. That's the best I can explain it.