Lost reverse, Mercuy 9.8

[cwphoto]

I've got a 1985, Mercury two-stroke 9.8. A whopping five hours of run time. I'm not sure what has changed but I can no longer get the motor in reverse. The manual talks about not putting the motor in reverse unless the engine is running or damage may result. I don't really get the connection. I did replace the impeller recently, so that's the only connection I can make. I would think I would have had an problem right away though, and I did not. Seems to run and work just fine, and then just stopped.

Any ideas on what to check for? I'm going to go study the linkage a little more closely, but thought I would ask as maybe I'm missing something obvious.

Troy

 

[KMixson]

Not sure about a Mercury, but on my 9.9 Evinrude I used to have you had to get the throttle down to right at an idle before you could shift it. You could check the linkage to make sure it is at a low enough idle to shift.

 

[JMichael]

If you recently had the lower end off, my guess would be that something came loose from the shift linkage or you didn't get it adjusted correctly when you reassembled it.

 

[crazymanme2]

If you recently had the lower end off, my guess would be that something came loose from the shift linkage or you didn't get it adjusted correctly when you reassembled it.

X2

 

[cwphoto]

Thanks for the reply folks. I think perhaps it's skipped a tooth. I manually played around with the prop and shift lever and got it to engage. I then fired it up and while it's a little stiff, it does go into reverse now. Shifting is only possible at super low RPMs, and I think a recent adjustment to the air fuel ratio may have thrown it off too, as my min. idle went up slightly.

Here's a short little video showing some of the resistance: https://youtu.be/Tzp3uH0TaBg

At least it goes in reverse now! Thanks for all help folks.

Troy

 

[bird35]

I had the same problem. I took the cover off and discovered a washer had fallen into the linkage and was preventing the motor from shifting into reverse. I still worry about where the washer came from, but the boat has run well for a year since so I guess it was not important.

 

[richg99]

Yep, they should be running in order to put them in reverse.

 

[cwphoto]

richg99 » 23 Sep 2014, 13:53[/url]"]Yep, they should be running in order to put them in reverse.

I have read that the motor should be running to put in reverse, but can't s say that I understand the logic. The engine does not need to be running to put in forward, so why reverse?

 

[richg99]

Something about the "dogs" being aligned.??????

Mechanic told me that an alternative way was to gradually spin your prop ...with your foot.... until you feel the reverse selector device slip into gear.

 

[JMichael]

I think the lower unit of an outboard is like a very basic, no frills transmission. It doesn't include things like synchronizers to line the gears up and make them shift into a different gear easily or without any grinding. But they also don't need as many parts or space/weight as a full fledged tranmission either. :lol:

 

[crazymanme2]

The dogs in the lower unit need to turn until they line up to go into reverse.