did mercuiser change the size of their couplers/drive shafts over the years?

[Don S]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

Is the coupler OEM or aftermarket? I have had a couple of aftermarket couplers that are so tight a tolerance that you can put the coupler on the splined shaft if done carefully. But I could never get the drive to go into the coupler while on the engine and in the boat. Even though the alignment was fine using the alignment bar.

 

[stang32]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

UNFORTUNETLY, i did not install the motor & I have no clue as to its origin, i can say this, there is a good amount of grease @ the front of this coupler, all over my tape measure when i stuck it in.
so based on that, i say it is old/original

 

[achris]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

If it were me, I'd be pulling that engine out (it doesn't take long and is quite an easy job. I've done it about 10 times on mine) and checking that the drive goes on without the engine in place... Then pull the drive back off and check that it fits into the coupler.... If it's a yes on both accounts, then put the engine back in, do the alignment again and fit the drive.... But I would have the drive complete, so I can turn the input shaft using the prop.... But that's just me, I like doing things the easy way...

Chris.....

 

[Bondo]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

did mercuiser change the size of their couplers/drive shafts over the years?

Nope,.... They're ALL the Same, from the begining to current production,....

with the exception, that the Old I-4 GM motors, Used to use an input shaft, 'bout an inch shorter...

MC-1,... Alpha 1s,.... Gen.IIs,... even the Bravos...

 

[stang32]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

If it were me, I'd be pulling that engine out (it doesn't take long and is quite an easy job. I've done it about 10 times on mine) and checking that the drive goes on without the engine in place... Then pull the drive back off and check that it fits into the coupler.... If it's a yes on both accounts, then put the engine back in, do the alignment again and fit the drive.... But I would have the drive complete, so I can turn the input shaft using the prop.... But that's just me, I like doing things the easy way...

Chris.....

chris, i hear what your saying but I dont have a hoist to lift the engine fro mthe boat that is tall enough. only a standard (car) engine lift.
if i were to do that, wouldn't it be easier to remove the gimbal bearing & confirm the shaft fits in w/out the bearing in place? i know the drive mounts up to the gimbal housing, they are both gen II's.
after sleeping on it I feel my issue lies with alignment. the tool has to be shoved into the bearing to seat totally, I can not get a smooth fit. I have the engine supported w/a come along attached to a 4x4(beam) & I am lifting the engine up /down but as much as I do this, i am getting nowhere. each time I adjust the height, should I re-rest the engine on the mounts or can I get it right hanging in place by the come along until it slides smoothly?
how much should i turn the engine mount nuts when adjusting? 1/2 turn @ a time? 3 turns?
i mean, ok, i have the engine sitting on the mounts, no tension on the hoist & the tool going in & out but i have to wrap my fist around it to do so. now, should I turn the nuts(1 on each side) 1 full turn,2? 3? or 1/2 turn?
is it possible I keep just missing my sweet spot because my hoist moving the engine up/down too much?

 

[achris]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

I have no idea which way the nuts need to go... Where is the grease witnessing? Have a look at this video and it should explain everything for you...

Checking alignment: http://youtu.be/w118LGsYgY4

Chris.....

 

[stang32]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

i have watched this video several times &I wish the alignment on that boat was off so you can show how exactly to make the adjustments. i know if the witness marks are on the top, the engine has to go down, & vise versa. I found posts that say the tension should be off the hoist & engine sitting on the mounts. my next question is how much to tun the nuts each time. I have the tool slidding in snugly & requires effort. should I be taking 1/2 turn on the nuts @ a time or more?

 

[Bondo]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

should I be taking 1/2 turn on the nuts @ a time or more?

Ayuh,... 1/2 turn at a time is good,...

 

[achris]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

Nah, my boat's never off.

If the alignment is close, Then lift the engine SLIGHTLY and take the nuts down one turn at a time... Both the same, nice and even.... Then lower the engine back down and check again...

Chris.....

EDIT: I know Bond-o said 1/2 turn, but that's because he's a girl (no offense Bill )

 

[stang32]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

ok, I tried adjusting the engine again, no good. i finally yanked out the gimbal bearing & the tool still is not a smooth insertion & THE shaft still does not fit into the coupler. is it possible the splines got damaged on the coupler?
I am not seeing any damage but there is a lot of grease down inside there. I am lost guys & I am about to give up, I called the P.O. & he swears up & down that this drive was assembled to this boat when he bought it., he pulled the drive to replace the pump because water was not flowing(did not mention that before) but then again, I did not threaten bodily harm before, he says while they pulled the drive to replace the pump, they installed bearing, & bellows as preventative maintenance, I looked @ the rear mounts & they look to be installed ok based on the manual
bolt
washer
spacer,
engine mount
double washer(cant see it but feel a space there
fiber washer & transom mount.

 

[stang32]

Re: did mercuiser change the size of their couplers/drive shafts over the years?

well i pulled the motor forward & removed the bell housing & coupler, the coupler does not fit the shaft. the shaft goes in & stops @ the point that the teeth start. Is it possible that the p.o. damaged the teeth when they tryed to get the drive on?
the teeth on the shaft look ok.
I am dying to get a new coupler to try it out. if the new couler fits correctly, I will cut the old 1 in half to see what the issue was.
while the engine was out, I saw that the water shutters are wiped out. this engine was cooked for sure.