Mercuriser alpha 1 gen 2 Out drive will not slide in the last 1"

[achris]

... I Have have attached a photo of the two shafts, same length, and diameter. but the one I'm trying to install does not have the center O-ring. Why? Is this a problem?

The one with the third 'O' ring is a Gen II... Are you trying to put a Gen I drive on a Gen II housing?

Chris......

 

[kenny nunez]

Do like the Doc said and if you can get a welder you can make your own tool as in post #3. You may have to really hit the bearing with your old shaft to “square” it in relation to the drive coupler.
The reason I asked about shaft length is from some crazy stuff that ended up at my shop in the past and you just cannot assume anything and have to ask some really stupid questions that sometimes gives a clue as what the problem is. That is the benefit of experience.
Try to rig up something to hold the weight of the drive so that all you have to do is balance it like in the video that Chris has. Good luck

 

[Maclin]

tazzerblue5 Since you are not including all the details from related posts here, I looked at older one of yours that said you had "the Gimble bearing and bellows replaced in my Alpha 1 gen 2 mercruiser".

Is the outdrive not a Gen 2?

 

[Bt Doctur]

Measure both of the shafts in the picture because it looks like the GEN II one is longer

 

[Bt Doctur]

https://forums.iboats.com/forum/eng...s/511281-alpha-one-gen-one-shaft-length-issue

 

[Bt Doctur]

so what engine does it have or a serial number, number of cylinders,

 

[tazzerblue5]

Ok, I'll add more info. both outdrives came off 4.3L I'll attach photo's of both and SN# if readable. shafts are within 1/16th of each other. Both sure look like Gen 2's to me... But I'm not a expert.. I did clean the groves for the 2 O-rings. And it could be hydro locked I guess. And to answer another's question, with 1" to go the shiftier is not engaged yet. One question is where does the middle O-ring on the shaft seal? and when did they change that? I have not attempted to reinstall it again..
edit: photo's left to right. 1, unit I'm trying to install, 2, it's SN #, 3, SN# of removed out drive, 4, old out drive.
From looking at the splines on the old shaft, it sure looks like there's 2" of contact area, which tells me the splines were already engaged by 1" when the drive has the last 1" to go? what say you all?

 

[Bt Doctur]

OK, both are gen ii`s so no problem there.The O ring in the middle is for a coupler with a snout VS the standard triangular coupler without the snout. Useless in my opinion because you should be removing the drive to service that area anyway..
An inch would indicate the alignment is off or the gimbal bearing is not aligned with the coupler.
Remove a input yoke ,tie a rope to it where the U joint goes , drive it in all the way, remove with a slight tug.If it cannot be removed the alignment is not correct.
Can also slide in a 1 inch dia pipe or rod to visually see if it is in the center of the gimbal bearing.

 

[tazzerblue5]

Thank You!

 

[stang32]

ok, 1 more thing, once your sure the alignment is right, (yoke installed as bt said) take some emery cloth and sand the end of the input shaft. there may be fine ridges that are cauaing it to hang up on the gimbal bearing. it happed to a boat i worked on this summer. the old gimbal seized up and was stuck on the shaft. i had to chisel it off. so the shaft was damaged. i spent a good 20 minutes sanding the shaft and it finally cleared up and went on smooth.

 

[tazzerblue5]

Well, I ordered the alignment tool, and it came today so tonight I tried to see the problem. Well I have more questions. The shaft only went in about 14.5 in from the out side edge. I'll post a photo, you can see where the gimble bearing rested, 1 1/8" on the largest part of the shaft. It feels like its hitting the edge of the coupler. No matter how i wiggled the tool it would not go in any farther. I measured the old drive and it looks like it slides in around 17.5 in. What do you think? haul it back to the dealer and ask what the FFFF he actually did? I think they'll just hose me some more. I don't have time to screw around with it right now, and don't need the boat either... Just very Frustrating. First photo of how far tool went in. you can see the grease line from the bearing.. 6 in. white mark is to outside of housing. 2nd photo is side by side with wood dowel, you can see on the wood dowel how far that went in and hit the flywheel, about 20 in. to the white mark.

 

[Bt Doctur]

Have no idea where you measuring the depth from but the most you can go in is 9 -9/16. This takes you to the outside edge of the gimbal bearing . If the large part of the tool enters the gimbal bearing ,your in.

 

[Bt Doctur]

If the tool goes in to this depth

your alignment is good. If not remove a shaft from the other drive and drive it in all the way to line up the bearing with the coupler

 

[kenny nunez]

2Xs on what the Doc is saying. Use the old shaft to check if the alinment is right. Since the outer carrier of the bearing is aluminum the dealership may have pounded it in and caused it to tighten up around the bearing making it hard to center the bearing. That is why I mentioned before that you may have to hit the shaft to square it in relation to the coupling.

 

[Bt Doctur]

You do have to drive the bearing in but you use a driver head to do it. Can`t use a piece of round stock

 

[tazzerblue5]

Ok, I'm hearing 2 different things, One put an old shaft in, hit it and it should align it. 2, from the video's they say to loosen motor mounts to align it.. My feeling is the Dealer was suppose to do this. That's why I took it there in the first place.. I did buy the complete alignment tool package. shaft, bearing installing disc, bellows installing piece, ect. I don't want to remove my old shaft I think that unit can be rebuilt.
To answer the measurement question, I measured out to the flat surface that the out drive bolts to, its flush and square. And if you look at the dowel I inserted it went in almost 20 in. ( White line) and hit the flywheel. So 14.5 to 20 is 5.5 in difference, I know it won't go all the way to the flywheel, but should go in 3+ more inches..

 

[achris]

DO NOT loosen engine mounts.

 

[Bt Doctur]

Until you have the bearing aligned correctly the alignment tool may not bottom out.
To try adjusting the front mounts before to have the bearing aligned is useless.
You could try hitting the tool with a good hand strike to move the bearing around in the gimbal to try and align it.
If that dosent work, remove a shaft and drive it in. This will align the bearing and you should just have to use finger pressure to pull it out. More than finger pressure indicates a mis-alignment

 

[Bt Doctur]

I don't want to remove my old shaft I think that unit can be rebuilt.

You will most likely be installing new U joints so its not an issue removing the shaft

 

[AKJohne]

This is what proper alignment should feel like.
https://vimeo.com/260111165

It can be tricky as the gimbal bearing can be aligned but not "centered", if the tool goes in take a mallet and smack the end of the tool perpendicular to the shaft, do nit drive it in by force. Hit the shaft form the sides and top and bottom while working the shaft in, this will center the bearing. It can be frustrating until its right, once its right you can feel it. You can move motor mounts and chase alignment all day, if the bearings not centered it will never feel right. It needs to slide in and out with two fingers. The tool really is not machined that tight so the shoulder hits and then it slides in.


Remove the additional O-ring to make sure that is not a issue.

taking it to a shop to do part of the work has some potential downsides as you are now questioning their work..... IMO you would be better off to let them do the complete job or do it all yourself. Learning can be painful....