Merc lower unit

[Plains Puddlerunner]

I have a Merc that has only forward, no nuetral or reverse. I checked and the shift pawl on the engine and the rod is turning. Is a lower unit rebuild beyond the novice mechanics ability? I have the service manual and it does not look all that dificult but considering the cost of a professional rebuild I am wary of tackleing this one. Any advice??? Thanks!!!!

 

[cutter]

Re: Merc lower unit

has anyone removed the lower unit? If so, it is possible that it was assembled with the shift rod improperly positioned. what model Merc?

 

[Plains Puddlerunner]

Re: Merc lower unit

Good thought on the shift linkage. The motor is a 1981 90 H.P. I6

 

[trevorcday]

Re: Merc lower unit

The most common reason for losing reverse is accumulated wear in the parts that make up the shift mechanism in the lower unit. The main area of wear is the teeth on the shift clutch and gear. Also the shift cam and follower will wear and provide less travel fot the clutch. If you disassemble the lower unit you can inspect the reverse gear and shift clutch. If the teeth (where the shift clutch engages) on the gear are badly rounded then you will need to replace it which requires special tools and training. If you can keep the existing gears and just replace the shift clutch, cam and follower you can probably do the job yourself. We use this approach at our shop when customers want the job done on a budget. It isn't really the best way to do it but it may work and save some dollars. <br /><br />While you have it apart you might as well replace all the seals and the water pump as well.

 

[Plains Puddlerunner]

Re: Merc lower unit

If this gear is worn would that take out nuetral as well? I plan to drop the lower unit this weekend and turn the shift rod by hand but would like to know if neutral would not function if the clutch is worn. Thanks for your response.