Prop won’t engage but throttle works

[S-Ellison]

I have a 75hp 2stroke mercury on a suntracker pontoon. Used it last year, all was fine. It’s trailer kept in a building. Got it out last week and changed the lower unit oil, charged the battery, fresh gas and fuel filter. Went to lake yesterday and going to launch off trailer but prop won’t engage. Forward or reverse. Throttle works on both but no prop. Any suggestions?

No shavings came out in used lower unit oil

 

[jimmbo]

Remove the cowl and verify that the shift cable is moving(don’t attempt to shift into reverse without the engine running). If cable moves, then more troubleshooting at engine end needed. If cable doesn’t move, then remote is suspect. Perhaps the gearshift disengagement button is stuck

 

[WesNewell]

Are you sure someone didn't pull the throttle out of gear? Did you try and push it back in?

 

[Texasmark]

If you have a Commander 3000 which is a "hidden cable" side (bulkhead) mount I'm sure you are aware of the "fast idle" function where you place the shifter in N and push in on the button located at the pivot point of the throttle-shift lever and while holding it in, you move the lever forward. This gives you throttle but no gear engagement. If the button sticks in the depressed position, you have your condition. Maybe a little WD 40 around it will break it loose, otherwise time to disassemble the control and lube it good.

I think Wes was saying the same thing, just a bit confusing to me so I thought I'd elaborate on his comment.

 

[S-Ellison]

I had a friend of mine whose boat savvy come over. We went through the cables back to the motor. All seemed ok. Ended up taking the lower unit off and the gear selector will engage the prop but you have to spin it more than a half rotation either way from neutral. It’s a 2002 model and just an assumption but I’m leaning towards a worn clutch dog or selector bevel. What you alls thoughts?

Also a huge thank you to Jimbo , Wes, and Texas. This is my first forum. Only had the boat for 2 years and looking forward to fixing this with some help from guys like you. Your insights are greatly appreciated.

 

[jimmbo]

Was the gearcase removed anytime between last Fall and this Spring?
When you dropped the Lower Unit, did you see if the Lower Shift Shaft was engaged with Upper Shaft? Also if you put the Unit back on, did you verify that the lower went into the upper?

 

[S-Ellison]

I had a friend of mine whose boat savvy come over. We went through the cables back to the motor. All seemed ok. Ended up taking the lower unit off and the gear selector will engage the prop but you have to spin it more than a half rotation either way from neutral. It’s a 2002 model and just an assumption but I’m leaning towards a worn clutch dog or selector bevel. What you alls thoughts?

Also a huge thank you to Jimbo , Wes, and Texas. This is my first forum. Only had the boat for 2 years and looking forward to fixing this with some help from guys like you. Your insights are greatly appreciated.

 

[S-Ellison]

Jimbo,

The gearcase wasn’t open at all since I’ve had the boat(2018). I’ve just drained and refilled the lower unit oil.

Yes, the lower shift shaft was engaged with the upper when we split it and also when it went back together. The lower shift shaft is the one that seems to be spinning farther then it should to engage forward/reverse.

after some more online reading and YouTube(lol), I’m starting to think maybe the pin that connects clutch dog may have broken. Or even the spring, not sure. I think with my buddies help I may take a crack at looking in there this weekend.

what do you think?

 

[Texasmark]

The pin locks the dog to the prop shaft. The shift mechanism determines the fore-aft position of the dog on the prop shaft hence determines the engagement in which gear or none. If the pin is broken then I agree, you will be able to move the shift linkage through the gears but the prop shaft won't get the benefit of the movement.

 

[Faztbullet]

Symptoms you describe are like a frozen and cracked carrier. Check the carrier housing to see if cracked at nuts behind prop at 12 and 6