Proper shaft alignment

[Joshua Dawn]

I just replaced my cutlass bearing, and in doing so noticed the lock nut on my stuffing box was split. I have re-installed the stuffing box and placed a new cutlass bearing. I find that my shaft is aligning a bit high to the coupling about an 1". I can shove it down so that it will slide into the coupling, but am not sure if this is the right thing to do. Should I take off the stuffing box and ensure that the shaft is in the centre of the sern tube. Any tips would be appreciated.

[lecomte38]

You use a .005" feeler gauge all around between the faces of the coupling.

If the faces are flush with each other loosen the stuffing box and rotate it a bit while the flanges are engaged. That should aline things.

If there is .005" clearance or more on any side of the flange then engine alinement is needed
good luck - andy

[Denr]

This missalignment is normal as the hull takes on a different shape when in the water as compared to on the hard in a cradle or on jack stands. I would reassemble the flange to the transmission. Don’t forget to run the seizing wire through the heads of the hex head bolts. Do not attempt to align your engine on the hard. Align the engine only after the boat is in the water and the standing rigging is at the desired tension.

[zerubb]

May seem a stupid question to some, but how do you go about aligning an engine?

[bsfree]

The only stupid question is the one you don't ask!
The engine is aligned by adjusting the nuts on the engine mounts. This will raise or lower the engine, and if you examine the mounts you should see there is provision for adjustment side to side as well. As Denr said, only make these adjustments in the water. Also, remember that the adjustments may be small, only a turn or two of the nuts alters things quite a lot, and check your flange distance for eveness often. You will see that the top nuts act as locking nuts and should be backed off a fair way, the nuts the engine sits on are the ones adjusted. You might want to mark the threads with colored marker so you can always return to where you started in case it all gets confusing. We all went through this the first time, and it really isn't too hard to do yourself.
Good luck

[soul searcher]

remember one thing Its called an engine alighnment not a shaft alighnment.
never move a shaft to an engine.
The shaft sould be centered in the boat from the factory so unless you have had damage to any of those components dont move it just support it and yes where it is centered in the tube. if you use a v block you can go outside and on small safts you should be able to turn the shaft with your fingers easily.once you kow the shaft is centerd then align the engine to the
shaft. I usually start with a quarter then go to a dime then get out the feeler guages. You can get it close on land and fine tune in the water.

[sailingdog]

Soul searcher's point is a very good one... moving the shaft can cause it to be misaligned in the strut or cutless bearing, which will lead to accellerated wear on the shaft, strut and cutless bearing, and an additional load on the engine.

[Gene T]

I generally find I need to lift the shaft a bit to be in the center of the tube. Then align the engine to the shaft. I use an Allen wrench to check clearances. I find the shape handy for telling how much off you are by just turning the wrench back and forth to check play. This can be a lot of work if you are doing it alone, (depends on access) and I find the allen wrench speeds up the process a lot. Don't forget to rotate the shaft 180 degrees and recheck the alignment.

[deniseO30]

I'd like to revive this thread. I'm ready to do the engine alignment now that the shaft, pss seal, cutlass and things are all back in the boat. still on the hard but I would like to get some practice doing it. It "looks" pretty well centered and the hubs also "look" even on all for points.

Also.. where do I find new set screws with the holes drilled for wire? The bolts for the hub to transmission need replacement also. what should we use for those, stainless fine thread?

thanks all!

[Omatako]

FWIW, when I align a shaft there are two things of importance:

• The shaft must come up and align from a height perspective as exactly as possible without any pressure applied. So the bolts should slide in effortlessly in a totally natural state of rest.
• When offering one flange up to the other, the alignment is critical. I measure it with a feeler guage and like to get it to within 0.005" . Anything more than this will cause a vibration even if to you it is imperceptible.

And such a degree of accuracy is not hard to achieve so I always do it.

Andre