Position of Shift Shaft before Pulling upper and lower together?

[ixousdan]

After changing my impeller and reasembling (1994 60HP Mercury), out of water tests seem to indicate that I have only forward gear, no reverse. The gear housing splines will rotate about 200 degrees while the connector from the shifter, only rotates about 40 degrees when moved to reverse and then 40 degrees the opposite direction when moved to forward position. So I think I need to know where the gear housing splines should be set before pulling upper and lower units together. More clockwise or mostly counter clockwise or somewhere in the middle? Shouldn't I be able to set the gear housing shift rod/splines all the way to the right or the left and as I rotate the drive shaft clockwise, observe the propeller turn in different directions??

 

[Dave1027]

Re: Position of Shift Shaft before Pulling upper and lower together?

You need to have both the shifter and LU in the same gear before pulling together. That's all that's required.

As far as turning the driveshaft to test each gear. Don't turn the drive shaft the wrong direction and bind the impeller. But you really don't have to turn the drive shaft. If you spin the prop or propshaft it will ratchet in the proper direction.

 

[ixousdan]

Re: Position of Shift Shaft before Pulling upper and lower together?

I am still concerned with the fact that the shift rod in the LU rotates almost three times further than the shift rod connector in the upper unit that is attached to the shift control. That means I could be off the correct setting by over 100 degrees in the LU. Is there some guideline that would get me close before closing the unit with another trial and error? Like I said earlier, I don't seem to find neutral or reverse when turning the propeller and adjusting the LU shift rod by hand. Trying to understand.

 

[latin monkey]

Re: Position of Shift Shaft before Pulling upper and lower together?

did you have a problem with the LU shifting before you changed impeller? you should be able to shift it by turning the shift rod in the LU. the shifter at the top of the shift rod at the powerhead needs to be in neutral and so does the LU when you reinstall it, sometimes its a pain to get it right but be patient and you will get it eventually

 

[Dave1027]

Re: Position of Shift Shaft before Pulling upper and lower together?

Maybe you are turning the shift shaft the wrong way and spinning the cam away from the follower. Turn it the other direction.

 

[j_martin]

Re: Position of Shift Shaft before Pulling upper and lower together?

Some say have both in reverse. That is so that you can move the driveshaft by moving the prop to align it with the crankshaft splines. I put both in neutral, because both have a very definite detent at that position. I then talk the CFO into rocking the flywheel to align the driveshaft and crankshaft splines. That's on a V6. One could do it alone on a smaller engine.

that's my story, and I'm sticking to it.
John

 

[ixousdan]

Re: Position of Shift Shaft before Pulling upper and lower together?

Last night I started with the shift shaft in the center (of the 200 degree possible rotation). Then tried all the way to the what would be reverse, then all the way to the opposite direction to forward. No luck getting the engine out of Forward. I touched the spinning propeller with my shoe and it was definitely spinning because it was in gear, not because of vibration. I can observe my shift control moving the shift shaft both directions before I close the unit. The shaft connected to the shift control moves equi-distant from neutral to F and R, about 40 degrees both directions from center. So it appears that the lower unit is just stuck in forward. I don't know how the lower unit shifts or what it looks like inside. Can you advise from this point?

 

[ixousdan]

Re: Position of Shift Shaft before Pulling upper and lower together?

There was no problem with shifting before I changed out the impeller. I did rotate the shift shaft position during the procedure not thinking ahead to what problems that might cause. Maybe I could remove the impeller again and rotate the drive shaft/propeller in the opposite direction with the shift shaft in various positions until I observe some change, like finding neutral or reverse. It seems to be stuck in forward.

 

[Moody Blue]

Re: Position of Shift Shaft before Pulling upper and lower together?

So the lower unit is installed already? How are you getting 200* of rotation on the shift shaft? The linkage will only allow about 90*.

If you've had the LU off and messed with the shift shaft, then its quite probable that you have misaligned the upper and lower shift shafts.

The shift shaft on the lower unit rotates about +/- 45* from center (neutral) to engage the gears (CCW to reverse, CW to forward) then spins around into no-mans land of about 270*. If you've turned the lower shift shaft into the no-mans land before reassembling then there won't be enough rotation from the upper linkage to get it into gear and you are stuck in a sort of FWD gear.

You will need to drop the LU and put both the control AND LU into neutral. Only turn the lower shift shaft CCW to be safe. It can rotate 360*. Due to the shape of the shift cam, you may twist or break the shift shaft if you try to rotate it CW. As you turn the shift shaft (use 9/32" socket over the end of the shaft and a ratchet to turn it) there will be lots of freeplay then resistance. That will be entering FWD gear. Should feel a slight detent as you continue to rotate and that will be FWD gear. Continue rotating until a firm detent is felt, that is neutral. Rotate more and you will feel another slight detent which will be reverse. Rotate more and you are back into no-mans land.

Once you feel comfortable that you have identified all three gears, it is safe to shift CCW and CW between FNR. Remember, don't turn CW if you get past the REV detent, just continue to turn CCW until you hit the FWD gear lobe again.

So again, put everything into neutral then reassemble.

Good luck.

 

[ixousdan]

Re: Position of Shift Shaft before Pulling upper and lower together?

Thanks Moody Blue. Your information got me out of the fog. I needed to know that the shift shaft could fall into a large no-mans land area opposite the true gear area. I was looking for the gears to engage in the no-mans land. The wrench remark told me there might be some tension getting it to the right area. Your description of the direction to turn and the order that I would find the gears made sense to me finally.

 

[Dave1027]

Re: Position of Shift Shaft before Pulling upper and lower together?

That's exactly what I was trying to tell you. I guess Moody Blue said it more eloquently.