Shift Problems

Tuffy1

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Joined
May 28, 2016
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Motor is 1991 Merc Outboard Tiller 40 hp 2 stroke 4 cyl.

After pulling and reassembly of bearing carrier and lower unit I cannot shift into nuetral or reverse.

With the lower unit off and the bc and prop shaft installed i can rotate the shift shaft to select gears. In forward prop ratchets cw and is tight ccw. In neutral prop spins freely. In reverse, its the same as in forward.

With the lower unit installed and the bc and prop shaft removed I can see the cam shifter move when i move the shift lever. It appears to be postioned correctly.

With everything together it just stays in forward. Ive pulled it apart multiple times and cannot figure out what i am doing wrong.

Please help.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
F gear has the least amount of tension. You have eliminated your hand operated shifting linkage mechanism in what you have done. The only thing missing in what I see is that you haven't turned the cam against the pressure of the spring inside the prop shaft from the shifter handle, whatever and wherever that is.....not familiar with your specific engine.

With everything installed as if you were going boating, why not drop your lower unit just enough to see the end of the upper shift rod where it slips over the LU shifting spline and while watching, run your shift lever through the gears and watch it as you do. Does it turn the shift shaft the same amount that you turn it with a pair of pliers when the LU is removed? I'd bet not.

Going to bet you have a gear slipping, clamp loose, roll pin broken or worn, or somewhere along the line, either at the shift lever - shaft interface, shift rod to vertical shift lever arm, vertical shift lever arm to vertical shift shaft.

Give it a try.
 

GA_Boater

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May 24, 2011
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49,038
Welcome to iboats.

When the lower unit is reinstalled, is the lower and shifter both in the same gear? I usually put the shifter and lower in neutral for installing the lower unit.
 

Texasmark

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Dec 20, 2005
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14,544
He apparently has an offset problem, not the usual problem as you described..........seems to me that's what he said. I guess the hole he is talking about is the speedometer pickup hose hole.
 

GA_Boater

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Hole? What hole?

It is the typical problem where the shifter and lower unit shift shaft are not in sync. That's the reason for using neutral because the springs tend to hold neutral and the same springs easily allow the shift shaft to pop out of gear when the upper shift shaft is meshing with the lower.
 

Texasmark

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Dec 20, 2005
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Void reply. Confused this thread with one several down with a hole problem.
 
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Tuffy1

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May 28, 2016
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5
Hole? I'm lost...

I've tried re assembly with both in forward and in neutral.

Let's start here. With the lower unit off, is my prop behaviour correct when selecting gears? Forward and reverse will rachet cw and lock up ccw. Nuetral spins freely.

Could it be my bearing carrier is not seating properly? I see the manual says to rotate the drive shaft while installing, I was not doing that. It seems to go in all the way...
 

GA_Boater

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May 24, 2011
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It may be time to ask - What was the reason for removing the bearing carrier and did you remove the forward gear and seat it per the manual?

As long as the control is in neutral, you can turn the drive shaft all day long when installing the bearing carrier and it will make no difference as long as the forward gear is seated. Here is the boatinfo.no instructions if I picked the right motor http://boatinfo.no/lib/mercury/manuals/30-40_2cyl.html#/300-

Try this method - http://forums.iboats.com/forum/engi...od-of-shift-shaft-setup-for-mercury-outboards

I remove the spark plugs and turn the flywheel. It works every time.
 

Tuffy1

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May 28, 2016
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Bearing carrier was removed to replace prop shaft seals. I did not remove the forward gear.
 

GA_Boater

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Then seating of the bearing carrier shouldn't be a problem.
 

Tuffy1

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Joined
May 28, 2016
Messages
5
Solved. My shift lever in forward was not a precise match with the lu shifter in Forward and thus the shift rod was pushed up and not meshing. A little fiddling and all is working properly. Thanks for all the replies
 

GA_Boater

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May 24, 2011
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Good ya got it.

Time to go fishing, :joyous:

EDIT - Got crossed with another post about the hole.
 
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