Mercruiser will not go into gear

kidge

Cadet
Joined
May 15, 2012
Messages
6
Alright, I've got a 3.0 Mercruiser 130hp. 1987 Invader I/O. Took it out Sunday and it ran fine pulling people skiing and cruises in with ease after that. I did run through some heavy weeds when coming in, not sure if that would affect it.

Started it up today with no problem., the engine sounded great and then a squealing sound started similar to a bad belt but not as high pitched. Then I could not get the boat to go into gear either forward or backward and a couple times it even stalled. The prop would not spin. I had a.neighbor take a look and he seemed to think it could be wiring from the throttle but then why the funny noises? I did fry the impelled earlier this season but have had it out 4 times since and it ran great every time. Checked the oil and no problems there.

Anybody have some thoughts or ideas? Gear or shaft? Thanks.
 
Last edited:

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
19,011
Re: Mercruiser will not go into gear

I would start at the engine coupler and work my way down towards the propeller.
 

kidge

Cadet
Joined
May 15, 2012
Messages
6
Re: Mercruiser will not go into gear

Thanks and after doing a little Google search, consensus is that coupler failure is caused by poor alignment. My boat was WAY out of alignment, as the wheel would jerk to the right if you took a hand off. I was foolish not to get that taken care of.
 

81 Checkmate

Lieutenant
Joined
Jul 20, 2010
Messages
1,360
Re: Mercruiser will not go into gear

What tpenfield is talking about is engine alignment with your drive unit. so the drive shift rides stright and not in a bind. This would not have anything to do with the wheel jerk.

Try this... WITH THE BOAT TURNED OFF...put shifter in forward and check your prop does it lock in one direction and free in other direction., do the same for reverse.

If it doesn't lock up in either direction..... I would be looking into pulling the drive unit off.

Has the drive ever been off the boat???
 

kidge

Cadet
Joined
May 15, 2012
Messages
6
Re: Mercruiser will not go into gear

We did take the lower unit off to install a water pump kit and it didn't go back on too smoothly but its run for several hours since. I just read that car alignment can lead to coupler failure which can stop propulsion
 

dingdongs

Chief Petty Officer
Joined
May 29, 2009
Messages
649
Re: Mercruiser will not go into gear

remove earth then remove top cap off sterndrive so you can view gears.romove plugs so you can turn engine over by front pulley.see if gears are rotating.this should happen in neutral.report back.maybe the fork under the sterndrive has been bent due to forcing the lower on and not having everything in line.(we don't know 4 sure)then time to look at that fork and tell us what you have.pics may help.
 

kidge

Cadet
Joined
May 15, 2012
Messages
6
Re: Mercruiser will not go into gear

remove earth then remove top cap off sterndrive so you can view gears.romove plugs so you can turn engine over by front pulley.see if gears are rotating.this should happen in neutral.report back.maybe the fork under the sterndrive has been bent due to forcing the lower on and not having everything in line.(we don't know 4 sure)then time to look at that fork and tell us what you have.pics may help.

Going to lift the engine up which will allow us to get the.belt changed and some other things that had to happen eventually. I think its the rubberized dogbone hooked up to the flywheel that got damaged from when the water pump failed. I'll keep updates going for anybody else who has this problem.
 
Top