2015+ AR240 Tower Fix

[swatski]

I'm re-posting some of the information contained in thread with the warning about the AR 240 tower collapsing in a 2016 AR240 yammie. The thread is long and confusing, and I have received numerous inquiries - trying to post just the essential information here on the actual fix.

The tower locking mechanism is common to all post 2015 AR towers, in particular 2015, 2016, and 2017 AR240. The 2018 AR240 appears to use the same mechanism as well.

So far only one tower has been documented to actually collapse under sail, albeit the issue has affected numerous other AR240 boats that were discovered to have the critical locking bolts loosened up. Simply tightening those bolts up in time appears to prevent a catastrophic collapse. The torque, timing, and any other parameters required for that critical maintenance are not known, and not included in the Yamaha owner or service manuals. Yamaha's response has been muted/non-existent, and this OP has been denied any warranty coverage of the event and the resulting extensive damage - in a boat that at the time was under 1 year from new purchase, and covered by both factory and YES warranties.

This was initially not meant to be a permanent fix, but rather a temporary solution to increase safety while making the boat operable. However, after a fairly extensive use over many hours in the remaining part of the 2017 season the modified tower locking mechanism has shown no signs of being compromised. Therefore this may be the mod that fixes the issue permanently.

There are two major parts to this mod - 1. modifying the existing handwheel-bolt, and 2. loosening and re-tightening the hull cap bracket bolts.

The first part (handwheel bolt mod) alone is the key.
The second part is (almost) an overkill, but is highly recommended if the tower does not need to be raised and lowered repeatedly (for storage etc.).

Re-posted from https://jetboaters.net/threads/warning-2015-18-yamaha-“ar”-boat-owners-with-forward-swept-wakeboard-towers.14828/page-16
Post #319, page 16:

--

Okay, so I think I have come up with some pretty good workaround.
I have been working with a machine shop and they basically cleaned up and rejuvenated my bolts and internal thread inserts (inside the mounts/brackets) - to work like new. The insert/internal threads are shorter (minus approx. 2 threads that were stripped/cross threaded in my tower) but the guys reassured me this is going to be better than redrilling/reinstalling. Please bear with me!

First off, this is NOT meant to be a SOLUTION, just a temporary fix. But I think it is pretty darned good, actually. The only drawback - this will NOT be ideally suited for those who need to put the tower up and down frequently. The mod will STILL WORK, but full implementation involves a special, final "tightening maneuver" that would be impractical for frequent use. (see below - at the end)

The idea is super simple - basically to lengthen the usable thread of the factory hand-wheel bolt - to increase the usable thread count from 6-7 turns per factory to approx 14+ (here). Moreover, a special implementation sequence ascertains those bolts are going nowhere! as far as potential pull out (no early withdrawals).

There are no new parts involved, just some modifications of the existing (two) bolts. If necessary, those hand-wheel bolts can be replaced for some $40 a piece (Screw, Knob F3F-U724D-00-00 $39.27) - so there is an easy way to go back to the original setup. Those are the only parts that get modded - the two bolts.

Here is the long and short - in one picture - factory on the left, modified on the right:

Here is couple more pics, different angles:

Here is the difference (qualitative view) in the reach on the inside
Unmodified (before):

And modified (after):

Here is how the bolts sit inside the tower - approx 3/8-1/2" deeper than the factory (after):

Before:

After the bolt modification, the spring and plastic washer NEED TO BE REMOVED. Also remove /do not reinstall the nylock nut. This is to permit a deeper reach of the bolt - a critical part of this mod/approach.

Here are two short video clips showing the movement range of the modified bolt with and without the spring/washer.

First one is of the bolt (modified) WITH the spring and plastic washer in place:

This does NOT work well - not enough threading depth.

And here is the exact same bolt W/O the spring and washer:

This is good - can be threaded in aprox 14+ turns.


And here is the most important part.

Hand wheel wrapped in a towel and tightened with a wrench - into the base/mount/bracket. However - BEFORE the modified hand-wheel bolt is put in place and tightened, the under-the-hull-cap bolts holding the bracket are loosened up. Those are 3/4 nuts, deep socket, can be reached with and extension bar or by removing the speaker in the coaming above the rear seats.
(don't worry, in most boats those will be a bit loose already... so just do not re-tighten UNTIL after tightening the hand wheel bolts)

Those bolts (under the hull cap) are tightened AFTER the hand wheel bolts are in place - this puts sideway pressure on the bolts making it essentially impossible for them to pull out!

And there you have it. Let me know what you think.


EDIT: I finished after dark so no more pics. I also do not want to post pics of the whole job for other reasons.

EDIT 2 (for clarification):

Within the existing mechanism, increasing the length of thread engagement seems to be the key to safety.

One can do this easily by (adopting @McMark's new bolts idea or) grinding/filing the factory bolt plastic stem (as in above) AND removing the spring/washer/nut from the factory bolt to enable it to thread in deeper.One can get almost an inch of engagement with the modified factory bolt. That would pretty much guarantee some much greater level of safety without any additional mods.

The only inconvenience really is longer time for deployment (14+ turns vs 6-7) and the inconvenience of not having the spring to bounce it and the possibility of loosing the bolt (which would not be secured with the nut - internal, inside the leg).

--

 

[MrMoose]

Thanks for sharing your insight @swatski.

 

[swatski]

Quick update:
ZERO issues with the mod after about 150 new hours in my boat (past the incident/tower bolts failure).

Obviously, with this mod, folding the tower becomes impractical/impossible which can be a serious drawback for some (I do not fold the tower).
That is the only caveat with this mod I know of.

--

 

[Jonathan Pisarczyk]

@swatski is there an easy way to adjust the washer-cable setup that holds the tower in place when tower is lowered? My starboard side cable doesn't have any tension when tower is lowered. I tried to climb under the seat but had a hard time playing with the nuts and washer. I was able to use a 3/4 socket with extension thru speaker hole to tighten my nuts under tower bracket. Thanks for the tip!

 

[swatski]

Bumping this thread for new AR240 owners who ask. At this point I believe I can say with confidence this mod works very well.

With enough hard hours put on the clock since the fix even wife stopped asking if we are safe under that tower. Zero issues.


—

 

[EmeryZ28]

So, if my two knobs on the tower are as tight as I can possibly get them by hand, it could still not necessarily be secure?? Is that what you are saying?

 

[swatski]

So, if my two knobs on the tower are as tight as I can possibly get them by hand, it could still not necessarily be secure?? Is that what you are saying?

Correct. The bolts in question are under the hull cap. If your tower seems taut and the base has no movement when the tower is shaken vigorously, it's probably okay and may not need any immediate attention. Just something to keep an eye on.

@Mainah post, and my follow up, describes the process in detail.

And yes, most definitely keep an eye on the handwheel bolts. You do not want those to get loose, bad things can happen fast. Let's just say it not the greatest Yamaha design.

--

 

[kgower]

I'm re-posting some of the information contained in thread with the warning about the AR 240 tower collapsing in a 2016 AR240 yammie. The thread is long and confusing, and I have received numerous inquiries - trying to post just the essential information here on the actual fix.

The tower locking mechanism is common to all post 2015 AR towers, in particular 2015, 2016, and 2017 AR240. The 2018 AR240 appears to use the same mechanism as well.

So far only one tower has been documented to actually collapse under sail, albeit the issue has affected numerous other AR240 boats that were discovered to have the critical locking bolts loosened up. Simply tightening those bolts up in time appears to prevent a catastrophic collapse. The torque, timing, and any other parameters required for that critical maintenance are not known, and not included in the Yamaha owner or service manuals. Yamaha's response has been muted/non-existent, and this OP has been denied any warranty coverage of the event and the resulting extensive damage - in a boat that at the time was under 1 year from new purchase, and covered by both factory and YES warranties.

This was initially not meant to be a permanent fix, but rather a temporary solution to increase safety while making the boat operable. However, after a fairly extensive use over many hours in the remaining part of the 2017 season the modified tower locking mechanism has shown no signs of being compromised. Therefore this may be the mod that fixes the issue permanently.

There are two major parts to this mod - 1. modifying the existing handwheel-bolt, and 2. loosening and re-tightening the hull cap bracket bolts.

The first part (handwheel bolt mod) alone is the key.
The second part is (almost) an overkill, but is highly recommended if the tower does not need to be raised and lowered repeatedly (for storage etc.).

Re-posted from https://jetboaters.net/threads/warning-2015-18-yamaha-“ar”-boat-owners-with-forward-swept-wakeboard-towers.14828/page-16
Post #319, page 16:

--

Okay, so I think I have come up with some pretty good workaround.
I have been working with a machine shop and they basically cleaned up and rejuvenated my bolts and internal thread inserts (inside the mounts/brackets) - to work like new. The insert/internal threads are shorter (minus approx. 2 threads that were stripped/cross threaded in my tower) but the guys reassured me this is going to be better than redrilling/reinstalling. Please bear with me!

First off, this is NOT meant to be a SOLUTION, just a temporary fix. But I think it is pretty darned good, actually. The only drawback - this will NOT be ideally suited for those who need to put the tower up and down frequently. The mod will STILL WORK, but full implementation involves a special, final "tightening maneuver" that would be impractical for frequent use. (see below - at the end)

The idea is super simple - basically to lengthen the usable thread of the factory hand-wheel bolt - to increase the usable thread count from 6-7 turns per factory to approx 14+ (here). Moreover, a special implementation sequence ascertains those bolts are going nowhere! as far as potential pull out (no early withdrawals).

There are no new parts involved, just some modifications of the existing (two) bolts. If necessary, those hand-wheel bolts can be replaced for some $40 a piece (Screw, Knob F3F-U724D-00-00 $39.27) - so there is an easy way to go back to the original setup. Those are the only parts that get modded - the two bolts.

Here is the long and short - in one picture - factory on the left, modified on the right:

Here is couple more pics, different angles:

Here is the difference (qualitative view) in the reach on the inside
Unmodified (before):

And modified (after):

Here is how the bolts sit inside the tower - approx 3/8-1/2" deeper than the factory (after):

Before:

After the bolt modification, the spring and plastic washer NEED TO BE REMOVED. Also remove /do not reinstall the nylock nut. This is to permit a deeper reach of the bolt - a critical part of this mod/approach.

Here are two short video clips showing the movement range of the modified bolt with and without the spring/washer.

First one is of the bolt (modified) WITH the spring and plastic washer in place:

This does NOT work well - not enough threading depth.

And here is the exact same bolt W/O the spring and washer:

This is good - can be threaded in aprox 14+ turns.


And here is the most important part.

Hand wheel wrapped in a towel and tightened with a wrench - into the base/mount/bracket. However - BEFORE the modified hand-wheel bolt is put in place and tightened, the under-the-hull-cap bolts holding the bracket are loosened up. Those are 3/4 nuts, deep socket, can be reached with and extension bar or by removing the speaker in the coaming above the rear seats.
(don't worry, in most boats those will be a bit loose already... so just do not re-tighten UNTIL after tightening the hand wheel bolts)

Those bolts (under the hull cap) are tightened AFTER the hand wheel bolts are in place - this puts sideway pressure on the bolts making it essentially impossible for them to pull out!

And there you have it. Let me know what you think.


EDIT: I finished after dark so no more pics. I also do not want to post pics of the whole job for other reasons.

EDIT 2 (for clarification):

Within the existing mechanism, increasing the length of thread engagement seems to be the key to safety.

One can do this easily by (adopting @McMark's new bolts idea or) grinding/filing the factory bolt plastic stem (as in above) AND removing the spring/washer/nut from the factory bolt to enable it to thread in deeper.One can get almost an inch of engagement with the modified factory bolt. That would pretty much guarantee some much greater level of safety without any additional mods.

The only inconvenience really is longer time for deployment (14+ turns vs 6-7) and the inconvenience of not having the spring to bounce it and the possibility of loosing the bolt (which would not be secured with the nut - internal, inside the leg).

--

Dealing with this issue now on our 21 195s. Going to start with a thread chaser, but in all likely hood will have to modify the hand-wheel bolt as you have described above. thanks for taking the time to post and educate me / the forum.