1996 alpha genII shift shaft has dropped

[vogelBoats]

Hi all,
I was pulling into the marina and boat was running and shifting fine all day then it started stalling. I pulled up to the dock and was unable to get the boat to go into gear without it stalling. I had to get towed to the trailer and got the boat off the water. Upon further inspection, I noticed the lower shift shaft had dropped about a half an inch causing me to be unable to shift the boat into gear. I got a pair of pliers and squeezed the lower and upper together and it fixed the problem. boat shifts fine now and doesnt stall anymore. I'm afraid that it will happen again. What causes the shift rod to fall down, and how can i fix it? Thanks.

 

[stonyloam]

Re: 1996 alpha genII shift shaft has dropped

Just a guess, but there is a retaining ring on the lower shift shaft, it may have slipped. Like I said a guess. Probably have to drop the gearcase to look.

 

[achris]

Re: 1996 alpha genII shift shaft has dropped

... I noticed the lower shift shaft had dropped about a half an inch causing me to be unable to shift the boat into gear. I got a pair of pliers and squeezed the lower and upper together and it fixed the problem. boat shifts fine now and doesnt stall anymore. I'm afraid that it will happen again. What causes the shift rod to fall down, and how can i fix it? Thanks.

That can't happen. The lower shift shaft has a spline on the end that fits into the shift crank, and it fits all the way down. And if the shift crank broke, then you wouldn't be shifting any gears... What could have happened is the upper shift shaft has moved up in the bell housing. Pull the drive and check it all out...

Just a guess, but there is a retaining ring on the lower shift shaft, it may have slipped. Like I said a guess. Probably have to drop the gearcase to look.

The retaining ring only stops the shaft coming up, not down....

Chris...

 

[stonyloam]

Re: 1996 alpha genII shift shaft has dropped

The retaining ring only stops the shaft coming up, not down....

Thanks Chris: I read that as him pulled the lower up, didn't think of pulling the upper down. Seems like if it went up it would disengage from the shift slide, the only way it cold go down, is if the shift crank (in the gearhousing) dropped, or was split allowing the shaft to slide down, doesn't seem likely. Anyway the drive has to come off to figure it out. I guess the question that needs to be answered is: Did you pull the lower ss up, or the upper ss down?

 

[vogelBoats]

Re: 1996 alpha genII shift shaft has dropped

I'm not sure if the lower came up or top came down when i squeezed 'em together. If it was the upper, what should i look for to fix it?

 

[vogelBoats]

Re: 1996 alpha genII shift shaft has dropped

I just went out and pried the two apart with a screw driver (not much effort). The upper shaft slid up about 1/4 inch and lower shaft slid down about 3/8 of an inch. The two barely contact each other when apart causing me problems.

 

[Bt Doctur]

Re: 1996 alpha genII shift shaft has dropped

guys, listed as GEN II , dosent have the setup for a Alpha. If that shift shaft dropped ,the C crank had to break.

 

[stonyloam]

Re: 1996 alpha genII shift shaft has dropped

Agree with the Dr. The splines should be bottomed out in the shift crank and not move much if at all. On an alpha 1 if you try to put the lower and upper together (on the boat) and the upper and intermediate ss are not mated properly (crossed) it can put enough force in it to seriously bend the washer under the i ss. I assume if the same thing happened in a gen II I guess you could damage your shift crank 39: here http://www.mercruiserparts.com/Show...c=GEAR+HOUSING(PROP+SHAFT)(STANDARD+ROTATION)

 

[Bt Doctur]

Re: 1996 alpha genII shift shaft has dropped

Unless you have the Alpha type

 

[vogelBoats]

Re: 1996 alpha genII shift shaft has dropped

I'm not sure if anything is broken. The boat runs and shifts fine when the two are together. Here is how far I can pry them apart:

Then together

 

[vogelBoats]

Re: 1996 alpha genII shift shaft has dropped

You can see in the pictures that the top piece has come down some. Is there something that should keep it in that position?

 

[Bt Doctur]

Re: 1996 alpha genII shift shaft has dropped

need to verify what shaft is moving, is it the lower one or the upper one. the pic on the left shows no gap above the shoe, the one on the right shows a gap. that upper shaft is pinned in position and cant move up or down that much.

 

[Don S]

Re: 1996 alpha genII shift shaft has dropped

The upper shift shaft is only moving a very small amount, and is not your problem. The shift shaft in the lower has issues, and you need to take the lower unit apart and look at the shift crank. (Item #2 in the picture below.)

 

[vogelBoats]

Re: 1996 alpha genII shift shaft has dropped

need to verify what shaft is moving, is it the lower one or the upper one. the pic on the left shows no gap above the shoe, the one on the right shows a gap. that upper shaft is pinned in position and cant move up or down that much.

Both shafts move. The upper moves a small amount and lower moves a bit more.
I'm fairly mechanically inclined and need to know if taking apart the lower unit is something i can do?
Are there any special tools required?

 

[Bt Doctur]

Re: 1996 alpha genII shift shaft has dropped

the manual for the drive
I'm fairly mechanically inclined = you have to be atleast a 8 or a 9 on a scale of 10
special tool to remove the carrier nut in the lower unit if removable, otherwise you drill it out and you need the tool to install the new one
special tool to remove the nut just below the water pump to release the driveshaft
grinding a 7/8ths wrench a bit thinner for the pinion nut.

 

[vogelBoats]

Re: 1996 alpha genII shift shaft has dropped

About how much does it cost to have the lower unit rebuilt?