90 Mariner No reverse troubleshoot help needed

[incharleston]

I have a 1992 3 cylinder Mariner 90 motor.
What I know so far!
When on land w/ engine running the motor will shift into reverse and seems to spin fine.
When I put the boat in the water and shift to reverse it sorts of grinds and goes nowhere.
Any ideas on what order of things to check. I pretty good mechanically, but....
Any assistance would be greatly appreciated.

 

[Texasmark]

Re: 90 Mariner No reverse troubleshoot help needed

Sounds like the teeth on either your shifting shuttle and/or mating sockets on your reverse gear are worn out. They are supposed to be square, either 3 or 6 pair (teeth/sockets) but sloppy, long term usage, can round the square corners off and any load applied (like in the water with a prop trying to push against it) will cause it to slip out... The shifter is spring loaded internally which allows this to happen....wasn't spring loaded to allow this to happen, but since it is, wear will cause it to jump out.

Removal of the prop and then the propshaft/carrier bearing assy will be required to solve the problem. Not rocket science, but works better with a trained mechanic as there are some shims to insure are correctly installed.

Mark

 

[incharleston]

Re: 90 Mariner No reverse troubleshoot help needed

Wow! thank you so much for your reply. It will be a few weeks before I can start working on it, but I will let you know my progress. Thanks again