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LiquidForce
08-08-2012, 05:37 AM
Just had a discussion with a buddy and his boat (not a MasterCraft) manual says the transmission/crankshaft output flange gap has to be measured with the boat in the water.
Is this true for MC boats as well? I really wonder if my dealer goes to all the trouble of putting the boat in the water just to check the mentioned gap.

tockit
08-08-2012, 08:44 AM
Just had a discussion with a buddy and his boat (not a MasterCraft) manual says the transmission/crankshaft output flange gap has to be measured with the boat in the water.
Is this true for MC boats as well? I really wonder if my dealer goes to all the trouble of putting the boat in the water just to check the mentioned gap.
I've never heard that and really don't understand how that would effect it.

93Prostar190
08-08-2012, 08:47 AM
Maybe the prop adds flotation?

:) just kidding no idea why unless they think the adjustment will change the packing box leak rate and the want you to be aware ?

LiquidForce
08-08-2012, 09:03 AM
Ha! :D

Back to topic: In detail, his manual says: boat in water, fully fueled, with a normal load of people. [Edit: Not a joke, he just sent me a picture proving the statement. Boat is a CC Super Air Nautique 210, so more or less similar to my X2]

The only reason for the "average load" I can see is that the hull bends when it is in the water. But that's just me.

Is there a similar statement in the MC manual?

mikeg205
08-08-2012, 10:04 AM
One more reason to have an MC inboard.

LiquidForce
08-08-2012, 10:56 AM
I cannot imagine that the flange adjustment would have to be done in the water on CCs and it would not matter for a Mastercraft.

dtc
08-08-2012, 11:01 AM
Back to topic: In detail, his manual says: boat in water, fully fueled, with a normal load of people. [Edit: Not a joke, he just sent me a picture proving the statement. Boat is a CC Super Air Nautique 210, so more or less similar to my X2]

Is there a similar statement in the MC manual?

I can add this; my MerCruiser manual (Sanger V215) has a statement very similar to the above. After learning so much from this site over the years, last season I decided to inquire without leading and I asked my local shop about checking alignment. The general response lead me to believe they, nor most other shops, ever perform this procedure properly, and at best if you specifically ask to have it done, the usual reply is ... why? is something wrong? Then they'll stick a feeler down there and say, "yep looks okay"!

TRBenj
08-08-2012, 11:59 AM
Yes, alignment should be checked on the water, in order to account for the flex in the hull. It is less important on inboard ski boats, which tend to have relatively small and stiff hulls... but it is still the proper way to do it. MC is not immune.

Dino Don
08-08-2012, 12:51 PM
Always did mine out of water on the trailer. Can you imagine what that would be like with the boat loaded with people and you all bent over trying to do that with your little gauge checking gaps???? Bad enough by yourself trying to get it right.

DRRICK
08-08-2012, 01:05 PM
In the water. If you want perfection with your precision. I found it made more difference when I was using a 3 bladed prop.

Rossterman
08-08-2012, 02:40 PM
As others have said, no matter how stiff or well built the boat, some movement is realized when going from the trailer to water. That being said, there is also flex while under power, turning, etc that changes the alignment slightly in those situations as well. The only variable is how much flex is experienced and is it too much change to then cause alignment issues when in the water/under power. Since most folks have had zero alignment related problems (bearing/seal failure, excessive vibration, shaft binding, etc) with their MC boats after doing the alignment on the trailer, the amount of deflection seems to not be so severe as to cause issues- likely due to the smaller amount of deflection found in MCs vs other brands due to more robust construction (If it was a Bayliner, they would probably have to use a flex coupling instead of a rigid coupling as they are real flexy fliers :) ). Bottom line is If you want it the closest to perfect, do the alignment in the water but you will likely never know the difference.