Prop shaft questions

[CJD]

I just bought our boat last fall and am new to the V drive. Just had a couple questions about it.

The manual says to check the prop shaft alignment each year with the boat in the water. It's very difficult to even reach the prop shaft coupler under and around the tranny and v drive. Are you guys checking the alignment that frequently...and does it tend to go out of alignment?

Also, the PO put a large hose around the prop shaft seal. It completely covers the packing nut and extends about 6" forward around the prop shaft. Is this to prevent slinging bilge water? Is it a common thing to add, or best to get rid of it?

[Zim]

I just bought our bought last fall and am new to the V drive. Just had a couple questions about it.

The manual says to check the prop shaft alignment each year with the boat in the water. It's very difficult to even reach the prop shaft coupler under and around the tranny and v drive. Are you guys checking the alignment that frequently...and does it tend to go out of alignment?

Also, the PO put a large hose around the prop shaft seal. It completely covers the packing nut and extends about 6" forward around the prop shaft. Is this to prevent slinging bilge water? Is it a common thing to add, or best to get rid of it?

Not sure about the hose thing on the shaft seal, but I don't check the prop shaft alignment on a yearly basis. If you feel some vibration, that would give reason to check, otherwise it's likely just fine.

[CJD]

Thanks, Mike.

I'm glad to hear it tends to stay in alignment. That must be a benifit of the all composite frames.

The coupling sits directly under the rear platform/engine firewall, so only way I can see to get both hands on the coupling is to bear hug the tranny, and then you can't see what your doing without a mirror.

[CJD]

And...I'm getting the impression from the lack of responses that nobody ever checks the prop shaft alignment on V-drives...

So, is everybody sending it to the shop, or just not worrying about it?

[CJD]

Maybe I asked the wrong question...


Should have been, has anybody ever checked their prop shaft alignment?

[2500HD]

Just got my vdrive so nope, but i am interested in the procedure. a simple search would probably work though.
My thoughts are if you have no vibrations or noticeable problems then all is probably well.

[CJD]

Hey thanks! I was beginning to wonder if anybody was out there.

I had some follow-up questions, but I guess I'll have to figure them out myself. I watched all the U-tube videos about how to do the alignment, and on the direct drives it looks like a 10 minute procedure to check it, and considerably more to actually align the shafts. Of course, all the videos are of the DD's. The V-drive prop shaft is really buried, though. It's hard enough to see it, let alone get to it to remove the bolts. Here is all I dug up:

The Supra owner's manual does not even mention aligning the coupling.

Both the Indmar and the Walter's manuals say to check alignment when summerizing each year. One says boat in the water, and the other is non-specific about the boat being either in or on the trailer.

So, I guess I'll let you know how it goes...

[CJD]

I just bought our bought last fall and am new to the V drive. Just had a couple questions about it.

The manual says to check the prop shaft alignment each year with the boat in the water. It's very difficult to even reach the prop shaft coupler under and around the tranny and v drive. Are you guys checking the alignment that frequently...and does it tend to go out of alignment?

Also, the PO put a large hose around the prop shaft seal. It completely covers the packing nut and extends about 6" forward around the prop shaft. Is this to prevent slinging bilge water? Is it a common thing to add, or best to get rid of it?


This is just a follow-up, for posterity:

First, the hose that the DPO wrapped around the log seal was to prevent the water, which was running past the shaft seal from slinging all over the boat. And, yes, the water was running like a faucet with the boat in the water! Here is the funny thing...all I did was remove the hose and hand tighten the log seal. That was it! It amazes me when people spend 10 times more effort treating the symptoms instead of just doing what is right. So, the shaft seal leak was fixed in 5 minutes.

Now for the coupling alignment.

It was off. Just so everybody knows, the shaft alignment being off does not have any symptoms...no vibration or noise. The first symptom you get is the failure of the tranny and/or cutlass bearings. The book recommends checking it every year, and I intend to check mine from now on.

As I thought, getting to the coupling is a true PITA. I can tell you every detail about how it feels, but I still have not seen the coupling. To work on it you have to bear-hug the Walters V-drive, with one hand on each side. Since you cannot see through the V-drive, it is all done by feel. Here is how it went, with some details:

1) There are 4 stainelss bolts that feed from the rear towards the front through the coupling. They are held with nyloc nuts on the V-drive side of the coupling. These are not hard to remove, but they are slow, as the ratchet can only turn 2 clicks at a time. Removing the raw water intake hose (2005 Sunsport 24V) helped...some...but not a lot. You are working entirely by feel, and the prop shaft has to be rotated to acces each bolt one at a time.

2) The recommendation is to have the boat in the water, so the hull is flexed as it will be driven for proper alignment. This is why I suspect the alignment is rarely checked on our trailored boats! After the coupling bolts are removed, the coupling is still stuck together. I had to start the engine and goose the throttle in reverse to break the coupling apart. Of course, this technique will only work with the boat in the water.

3) Now you can check the alignment using feeler gages. Check it up, down, left, and right. Spin the shaft 180 degrees and check it the same. If the location of the misalign stays in the same place, your shafts are good. If the misalign changes location when you turn the shafts, then one or both are bent.

4) I was scared stiff thinking about moving those old engine mounts to align the coupling. They looked badly corroded, and I feared the worst...that one or more were totally locked up. I was VERY pleasantly surprised when all 4 mounts moved, almost effortlessly when gently using a crow bar to shove on them. I first set the left-right alignment by loosening the slide bolts (1 on each front mount, and 2 on each rear). You loosen the large nuts, and tap the stud into the mount to unlock it. When done, just tighten the nuts, which pulls the stud back into the mount to lock it in place.

Once the left/right was good, I had to raise the rear mounts by one turn. Again, loosen the large lock nut and turn the threaded mounting post. When done, tighten the lock nuts.

My coupling is now perfectly aligned. I reinstalled the the 4 coupling nuts and bolts...blindly, of course.

It runs and feels...exactly the same!! But I now know I am not overloading the bearings for a later failure.

The whole job took 2-1/2 hours, including the boat launch and recovery.

[Zim]

Good info... thanks for the update. I guess now that you talk about what you were feeling for, I actually have tightened the 4 nuts/bolts on the coupling... but I never completely separated everything. I felt down there and a few of the bolts were almost entirely backed out of the nuts. Now that you mention this, I should probably check again this year just to make sure nothing loosened up over last season.

Thanks for posting!

[CJD]

This is a one year follow-up...

After a year I just re-checked the prop shaft alignment again getting ready for the season. .003" off at the top of the coupling. Last year it was spot on...so that will give you an idea of how much it can change in a year. I was concerned that we could have torqued the strut when we had a rope catch the prop last summer. Apparently that had no affect, since the gap was centered at the top instead of on the side. Also, to fix .003" gap at the top, it only took 1/4 turn CW on each of the two aft mount adjusters to get it back spot on. Time to go surfing!

[docdrs]

You may want to check you motor mount bushings as they can wear/fail. There have been issues with the fasting having a lip and cause bushing wear . I must have missed this post as I am a big proponent for checking alignment. It's a good way to verify props shaft trueness and you should be able to get it within .001