mercury optimax 225 shifting prob.

[mchales navy]

Heres the problem, coming in from fishing Saturday<br />the port motor all of a sudden just Revs real high. I brought the boat down checked for any alarms which there was none. The engine idles fine but will not engage into foward or reverse. Upon inspection of the engine it appears the connection for the shift is loose compared to the starboard engine. I didnt have time to really go over it but any suggestions as to what to check would be a big help. This is my first boat w/ outboards so please forgive me if i sound like a jackass. thankyou in advance.

 

[andy6374]

Re: mercury optimax 225 shifting prob.

If it was running fine, and then all of a sudden reved high... I would guess you have a spun prop, i.e., the inner hub of the prop is no longer connected to the prop. So the prop shaft spins, the hub spins, but the prop does not.

 

[mchales navy]

Re: mercury optimax 225 shifting prob.

Thanks Andy, I spun the prop by hand and the nut and shaft spun w/ it making me belive it wasnt a spun<br />prop . Would this be the correct check? also when i have the engine idleing and put it into gear(either f or r ) theres no clunck like its going into gear.

 

[andy6374]

Re: mercury optimax 225 shifting prob.

Usually a spun prop can still spin if spun by hand. A real test would be mark a spot on the hub and the prop, give it good throttle, and then make sure the lines are still lined up.<br /><br />But since you said you don't feel/hear the clunk when shifting into gear, it sounds like your shift shaft is not aligned in the lower unit. I never heard of this happening suddenly as in your case. To check, just undo the 6 bolts holding the lower unit on (don't forget the bolt underneth the trim tab), and keep sliding the lower unit downward until you can see the shift shaft. You don't need to fully drop the lower unit to do this. The shift shaft is on the side closest to the transom of your boat.<br /><br />If confused send another post

 

[mchales navy]

Re: mercury optimax 225 shifting prob.

Update!!!! I did what you said andy and marked the prop and the hub and hit the throttle and sure enough they werent lined up. Pulled the prop off and the hub was shot. Had a new hub pressed, popped the prop back on and i'm good to go. I didnt want to miss striper season. thanks again for your help.