Stuck at the finish line - pre-alpha drive install

erikgreen

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Jan 8, 2007
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3,105
So, after getting a used lower half, losing a magnet in it, and paying to get it cleaned out and pressure tested at the local dealer, I'm finally trying to install it on my boat.

I've also while the drive was off installed a new lower shift cable, new cable boot, shift arm, and cable ends, and installed the new style shift shaft bushings in the bell housing.

So now that all the new parts are in place, I've tried to get the drive on... no dice.

First I checked the alignment with my alignment tool, and I see even spline marks all the way around, as expected.

Then I check to make sure the water passage O-ring is in place (and held there with a little bellows adhesive) and the large ring is in place inside the housing (the thick one that compresses as the 6 nuts are tightened down), and I check that the drive is in forward and held there and the boat's shift lever is in forward, then I install the drive, making sure the lever on the end of the shift cable goes into the well on the drive instead of hanging up against the face (I did that once, I admit).

It goes in with just a little difficulty to a point just a little bit past where the castle nut that holds the input shaft assembly in the upper drive is inside the bell housing. I want to say this is where the first of the two O-rings hits the gimbal bearing maybe?

I've tried whacking it a couple times and wiggling, removing and re-inserting 3-4 times, plus rotating the input shaft a bit to move the splines.

I don't want to apply a lot of force unless it's needed... the 5 or so times I've installed it before it's gone in past this point without problems.

Suggestions appreciated,

Erik
 

Don S

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Re: Stuck at the finish line - pre-alpha drive install

Did you put new oring on the splined shaft that goes into the coupler and gimbal bearing? If yes, are you sure they were the right ones? Did you put oil on them (grease isn't really the best thing to use). Are you sure the drive and the shifter are both in forward gear?
 

ShaneCarroll

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Feb 10, 2009
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Re: Stuck at the finish line - pre-alpha drive install

I had a similar issue, and a couple people on this site recommended the "Mercruiser Kick." I was sure the alignment was good, and everything else was in place, and I was instructed to kick the outdrive once or twice and it should slide in. It worked for me, and no problems since then, but I don't know how you would feel about it.
 

jtybt

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Re: Stuck at the finish line - pre-alpha drive install

Could be your splines aren't lining up. Rotate the prop counter clockwise.
 

cr2k

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Re: Stuck at the finish line - pre-alpha drive install

If you do have the right O-Rings on the shaft and they are lubed it is time for the MerKick.

Did it come off hard?
 

coastalcruiser

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Re: Stuck at the finish line - pre-alpha drive install

if the alignment's good the tool should slide in real easy...
since its in forward turn the prop while your pushing until you feel the splines mesh at that point it will slide in. I would not force it or it may not come off. Like don S said double check the O-rings.
 

Wakesilver

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Re: Stuck at the finish line - pre-alpha drive install

Are you doing this by yourself? Do you have an outdrive stand?

I have tried and failed by myself (no stand). When the neighbor or son helps it goes much better.
 

Howard Sterndrive

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Re: Stuck at the finish line - pre-alpha drive install

Yeah, I find it takes two people...one to lie on the ground and make sure the shift linkage stays together, another to work at pushing the drive and turning the prop...
Whoever designed these should be ashamed. It takes so much finesse it's absurd. Once you've done a dozen or so, it seems simple.
When it finally slides in with a crisp thud you'll be happy.
Kinda like banging your head against a wall... feels good when you stop.
 

havasuboatman

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Re: Stuck at the finish line - pre-alpha drive install

Assuming you are following the above advice (except the kick) make sure you are keeping the driveshaft level and that the U-joints aren't "folding" as you push. When they do that, the edge of the U-joint catches on the rubber seal.
NEVER kick the drive into place. You said yourself, "it usually slides right in". Don't force it. If you think you have the wrong O-rings, take them off and try to put the drive on. If it goes, go get the right O-rings.
If your alignment tool can't be completely installed and removed, easily, using one hand, your alignment is incorrect. Don't use the spline marks in the grease to decide the alignment is right. That's not correct. You know the alignment is good when the alignment tool can be seated and removed without ANY binding. Hold it between your thumb and first two fingers and slide it out.
Use spline grease on the splines, oil on the O-rings.
 

erikgreen

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Jan 8, 2007
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Re: Stuck at the finish line - pre-alpha drive install

Okay, lots of good advice.

I'll double check the O-rings, they were good so I left them as-is, but they're not lubed. I'll also check the alignment one more time.. I recall that it was easy to put the tool in and take it out, but I may as well be sure.

I try to keep the U-joints from folding with my fingers as far as I can.. anyone have a better way to ensure they're not catching?

I'll give this another try this afternoon. I guess we'll see :)

Erik
 

myoldboat2

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Re: Stuck at the finish line - pre-alpha drive install

HS> Whoever designed these should be ashamed. It takes so much finesse it's absurd.

I agree with that 100%. It's ridiculous.

Erik, my old Late Model I sterndrive never goes on easy. My alignment is perfect, all lubing is per the Merc manual and the final few inches are always tough.

But if yours used to slide on easy, if I were you I'd try to find out what's different this time. Good luck with it.
 

wca_tim

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Re: Stuck at the finish line - pre-alpha drive install

I have one that slips right in and two that don't slip that last inch and a half unless I give them a bit of a kick ot tap with a handsledge on a piace of wood. this is past the point where the splines are already lined up. I'm assuming it is getting that front o-ring to slip into place. getting them off never seems to be a problem.
 

freeone

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Re: Stuck at the finish line - pre-alpha drive install

if your getting to the orings and it stops the splines are meshed. lube the o-rings. last week after 45 minutes of everything under the sun i pulled the drive out and lubed the rings and it slid right in.
 

bigskiohio

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Re: Stuck at the finish line - pre-alpha drive install

make sure the shifting foot and shoe are straight, keep mpressur on prop, it is a two man job to make it easier. i made a stand and my friend helped me and it slipped right on.
 

erikgreen

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Re: Stuck at the finish line - pre-alpha drive install

I actually have a large engine crane I use to hold the drive in place, but it seems like it was easier to align it not using it, since the crane forces a fixed height, and I can more easily adjust when lifting the drive by hand.

I didn't get a chance to lube and install it yesterday since my back is currently out of whack and I didn't have any help available. I'll see if I can try during the week sometime.

I did check the bell housing and drive out for problems, things sticking out, etc... nothing out of the ordinary, the new shift mechanism seems to be in the right place and is the right length. I'm not mushing the big thick o-ring seal out of place. The alignment bar slides in and out easily. I'm hoping lube on those O-rings will do the job for me.


Erik
 

racinrc14

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Oct 29, 2008
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Re: Stuck at the finish line - pre-alpha drive install

I have an 898 that really disagrees when it's time to go on, and an 888 that goes on with much less groaning. I find that a lot of grease on the upper gear housing snout (the area that slips into the big thick o-ring) makes installation easier, and oil on the shaft o-rings. Also, my alignment bar is made of steel, so inserting and removing it with three fingers as someone suggested would be tough, but any bar should slide in easily if the alignment is good. The condition of your coupler could be an issue, also. If the splines have worn to a pointed appearance, they will be a little taller, thereby making the hole a little smaller, producing an interference with the shaft. My 898 is like that. I know it sounds bad, but I give it a whack or two with a heavy piece of timber to get the last 3/4" or so. Some day I will pull the motor and replace the coupler, but I've had no trouble with it this season, and it came off for winterization last week without incident.
 

wca_tim

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Re: Stuck at the finish line - pre-alpha drive install

note that if when you're trying to get the drive to slide in, if you put an old prop on the shaft and gently turn it backwards after you feel the shaft hit the coupler, it'll both keep it in forward and turn the splines to let them line up. when the splines line up you'll feel it slip in and the prop won't turn any more, but the pressure on the prop will keep it in gear. If the prop turns easily, you'll know it's slipped out of gear and to pull it further out and try again.
 

45Auto

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Re: Stuck at the finish line - pre-alpha drive install

I had a pre-Alpha that slid right back on, but my Alpha and Bravo III both take the "Mercruiser kick" to get the last couple of inches and get the o-rings into the gimbal bearing.

Ok Tim, I've got to ask - why does it have to be an "old prop" to line up the splines? I always just use whatever prop is on it - or are you implying maybe that ALL my props are "old props" .........
 

wca_tim

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Re: Stuck at the finish line - pre-alpha drive install

I had a pre-Alpha that slid right back on, but my Alpha and Bravo III both take the "Mercruiser kick" to get the last couple of inches and get the o-rings into the gimbal bearing.

Ok Tim, I've got to ask - why does it have to be an "old prop" to line up the splines? I always just use whatever prop is on it - or are you implying maybe that ALL my props are "old props" .........

Considering I lift the drive and slide it in by hand... I guess I would just be really bummed if I accidentally slipped and boogered up the edge or a blade tip of one of the really nice props I have...

smart alec... :D

Maybe all of your props are old... I know I sure got some.
 

erikgreen

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Jan 8, 2007
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Re: Stuck at the finish line - pre-alpha drive install

Little epilogue here.

Tonight I summoned up my courage and took some aspirin, then tried again to mount the drive. I re-checked the alignment (good) cleaned off the input shaft splines, applied some fresh all-purpose grease and oiled the O-rings on the shaft.

After all that it went in on the second try, pushing with my shoulder behind the upper half of the unit.

:p:D:D

So now on to my next problem... adjusting the new lower shift cable.

Erik
 
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