Replacement of Upper Unit Shift Shaft

[iloveketchup]

Mine flat out corroded or broke off at the top. I can see a stub where it used to be looking down from an angle.

how involved is replacing it?

(this part, the head broke off)



What it should look like:



What mine looks like:



This boat is nothing but trouble!

 

[90stingray]

Re: Replacement of Upper Unit Shift Shaft

Oh my goodness! Are you replacing that upper? The lower shift paw should be straight forward for you to replace. Just split the halves. Don't forget your oil o ring between the halves!

 

[Don S]

Re: Replacement of Upper Unit Shift Shaft

It's not the "Upper unit" that is corroded, it's the bellhousing.
They usually get bent or broken if corroded and someone tried to force the drive off or on without everything being in forward. Then if they try to straighten it, it makes it even weaker until it finally breaks.
You will need to remove the lower to remove the remains of the old shift shaft, and to install the new shift shaft in the upper.
DO NOT forget to put a new quad ring around the oil passage hole between the upper and lower.

.

 

[iloveketchup]

Re: Replacement of Upper Unit Shift Shaft

sounds easy enough. my understanding is i'll have to split the lower from the upper and then remove the cotter pin. Do i need to remove the outdrive or just angle it so i can slip in the shaft into the bellhousing from the top?

yes, i'll remember the little O-Ring. I did the water pump and remembered to install it.

Yes, either i snapped it not being in forward and forcing it, or that's how i got it. The shift cables are kind of "unknown" condition as well but i'm not sure if that is enough. I bought the boat last year and never actually saw it shift right.

 

[Don S]

Re: Replacement of Upper Unit Shift Shaft

If it was my boat, I would remove the drive completely. Since you don't know the condition of the shift cable, now is a good time to find out.
With the outdrive off, disconnect the shift cable from inside the boat. From the outside, move the cable full stroke by hand. I should move smooth and very easy. If not, time to replace it. While the drive is off, make sure there isn't any water in the bellows, the ujoints and gimbal bearing are in good shape, the alignment is ok, and last but not least that the splines on the shaft going into the coupler are greased.

 

[stonyloam]

Re: Replacement of Upper Unit Shift Shaft

It is your intermediate shift shaft that needs to be replaced (#22 here http://www.mercruiserparts.com/Show...0065.png&inbr=2203&bnbr=60&bdesc=BELL+HOUSING). It is located in the upper part of the outdrive, so you need to remove the outdrive and split the upper and lower halves. When you put it back together the shift shaft slides onto the splines of the lower shift shaft (make sure the lower ss washer is in place). Make sure your control handle is all the way forward and that the lower ss is turned all the way clockwise (prop locks when turned CCW), and the top of the replacement shaft is pointing straight ahead to mate with the upper ss coupler. Good luck

 

[iloveketchup]

Re: Replacement of Upper Unit Shift Shaft

If it was my boat, I would remove the drive completely. Since you don't know the condition of the shift cable, now is a good time to find out.
With the outdrive off, disconnect the shift cable from inside the boat. From the outside, move the cable full stroke by hand. I should move smooth and very easy. If not, time to replace it. While the drive is off, make sure there isn't any water in the bellows, the ujoints and gimbal bearing are in good shape, the alignment is ok, and last but not least that the splines on the shaft going into the coupler are greased.

Thanks for the suggestion.

My intent is to not own this boat much longer than i need to. I have 3 in the yard and this one needs to go! This is my first and probably last I/O. I've never even had it in the water.

 

[iloveketchup]

Re: Replacement of Upper Unit Shift Shaft

It is your intermediate shift shaft that needs to be replaced (#22 here http://www.mercruiserparts.com/Show...0065.png&inbr=2203&bnbr=60&bdesc=BELL+HOUSING). It is located in the upper part of the outdrive, so you need to remove the outdrive and split the upper and lower halves. When you put it back together the shift shaft slides onto the splines of the lower shift shaft (make sure the lower ss washer is in place). Make sure your control handle is all the way forward and that the lower ss is turned all the way clockwise (prop locks when turned CCW), and the top of the replacement shaft is pointing straight ahead to mate with the upper ss coupler. Good luck

Ok, the control handle is all the way forward. the c channel on the bell housing is straight foward. isn't this neutral? If i take a wrench and try and take it (looking from underneath) to the right (pointing towards port side of boat), it won't stay.

does the outdrive have to be in forward to remove it?

this thing is just sticking... i know it's been off within the last year.

 

[iloveketchup]

Re: Replacement of Upper Unit Shift Shaft

i'm pretty sure this isn't the way the Merc manual says to remove the stern drive, but i didn't have the tool to remove the cover and screw with the u-joint nor am i going to remove engine mounts.

worked out fine, doesn't appear anything was broke :shrug:



it looks like the bellows were in okay shape... at least okay for someone else to worry about it in a season or two. Things were awfully greasy. I've never had one of these off and out.

 

[Don S]

Re: Replacement of Upper Unit Shift Shaft

i'm pretty sure this isn't the way the Merc manual says to remove the stern drive, but i didn't have the tool to remove the cover and screw with the u-joint nor am i going to remove engine mounts.

worked out fine, doesn't appear anything was broke :shrug:



it looks like the bellows were in okay shape... at least okay for someone else to worry about it in a season or two. Things were awfully greasy. I've never had one of these off and out.

What the hell have you done ???????
If it takes a tractor to pull the upper away from the bellhousing, you have either done something wrong, or there is some serious problems inside. That drive should have fell off the back of the boat.

I pity the poor fool that buys that boat from you

 

[iloveketchup]

Re: Replacement of Upper Unit Shift Shaft

What the hell have you done ???????
If it takes a tractor to pull the upper away from the bellhousing, you have either done something wrong, or there is some serious problems inside. That drive should have fell off the back of the boat.

I pity the poor fool that buys that boat from you

Don't let the fact i used a tractor make it appear I HAD to use a tractor to pull it out. I'm not a huge person so... work smart not hard.

It was more like a bump with the clutch. I only took it out about 3 inches then did the rest by hand. I couldn't get it more than about 1/2" off by hand, The 6 bolts were off and it appeared to be in forward.E

Even the manual (Seloc Mercruiser 1964 - 1986 Stern Drive chapt 10-7) and multiple videos online say they'll stick. There is two methods recommended:

1. removing the engine mount bolts and jerking the engine forward to free the driveshaft
2. essentially giving up, removing the top cover on the stern drive and disconnecting the u-joint.

If i damaged the gimbal bearing, then it had to be replaced anyway. Using a tow strap vs chain is easier on the aluminum.

 

[stonyloam]

Re: Replacement of Upper Unit Shift Shaft

Ok, the control handle is all the way forward. the c channel on the bell housing is straight foward. isn't this neutral? If i take a wrench and try and take it (looking from underneath) to the right (pointing towards port side of boat), it won't stay.

does the outdrive have to be in forward to remove it?

this thing is just sticking... i know it's been off within the last year.

No that is forward. The reason you have to have it in forward when you pull the outdrive is so that the top of the intermediate shift shaft will slide straight back out of the "C" channel connecting it to the upper ss. N is 1 position CCW and R is 2 positions CCW. It won't stay because the shift cable holds it in place.

Yes. Except in your case since the top of the intermediate shift shaft is gone, it does not matter :facepalm:.

From the looks of the bellhousing I am not surprised LOL.

 

[iloveketchup]

Re: Replacement of Upper Unit Shift Shaft

No that is forward. The reason you have to have it in forward when you pull the outdrive is so that the top of the intermediate shift shaft will slide straight back out of the "C" channel connecting it to the upper ss. N is 1 position CCW and R is 2 positions CCW. It won't stay because the shift cable holds it in place.

Yes. Except in your case since the top of the intermediate shift shaft is gone, it does not matter :facepalm:.

From the looks of the bellhousing I am not surprised LOL.

Thanks for the response. Before removing the outdrive I kept moving the shift linkages and went back to check. I came to the same conclusion. Either straight is forward or something is really, really wrong.

ya know... the bellhousing is just marine growth that's stuck on. I've had other parts look similar and after powerwashing you wouldn't have known. It's salt water critters.