Since I'm stuck out of the water for a month, I think I may tackle
that "someday" job and pull my shaft to replace the stuffing box hose.
I'd appreciate anyone who has had a shaftline with a Drivesaver apart
recently taking a look at this and giving me your thoughts:

Http://home.maine.rr.com/rlma/Stride...htm#Drivesaver

It looks as though the bolts in the gear coupling are studs. Is this
the case or are they bolts with heads inserted through the drivesaver
before assembly? I haven't got much clearance to work with and may
have to sacrifice and replace the studs by twisting them out with vice
grips and then replacing. If they are bolts instead of studs, I'll be
in a pickle unless I cut out the stuffing box hose first. I'm not
sure I want to commit to the job this year unless I'm sure I'll be
able to get the shaft out of the coupling.

My plan is to get the Drivesaver out, insert something between the
coupling halves that just bears on the shaft, and then use through
bolts through the coupling to jack the shaft out. Much depends on
getting that rusty set screw out. This was a fresh water boat so I
don't expect it to be quite as bad as it looks. I'm going to make a
dam around the screw with swimming pool epoxy and fill it with Liquid
Wrench for a few days first. It looks as though the through bolt
should drive out reasonably easily.

Despite all the bad things I've said about Drivesavers, I plan to put
it back just as it is because the boat is running smoothly enough and
I don't want to buy a new shaft at this point.

--

Roger Long

Roger Long wrote:
Since I'm stuck out of the water for a month, I think I may tackle
that "someday" job and pull my shaft to replace the stuffing box hose.
I'd appreciate anyone who has had a shaftline with a Drivesaver apart
recently taking a look at this and giving me your thoughts:

Http://home.maine.rr.com/rlma/Stride...htm#Drivesaver

It looks as though the bolts in the gear coupling are studs. Is this
the case or are they bolts with heads inserted through the drivesaver
before assembly? I haven't got much clearance to work with and may
have to sacrifice and replace the studs by twisting them out with vice
grips and then replacing. If they are bolts instead of studs, I'll be
in a pickle unless I cut out the stuffing box hose first. I'm not
sure I want to commit to the job this year unless I'm sure I'll be
able to get the shaft out of the coupling.

My plan is to get the Drivesaver out, insert something between the
coupling halves that just bears on the shaft, and then use through
bolts through the coupling to jack the shaft out. Much depends on
getting that rusty set screw out. This was a fresh water boat so I
don't expect it to be quite as bad as it looks. I'm going to make a
dam around the screw with swimming pool epoxy and fill it with Liquid
Wrench for a few days first. It looks as though the through bolt
should drive out reasonably easily.

Despite all the bad things I've said about Drivesavers, I plan to put
it back just as it is because the boat is running smoothly enough and
I don't want to buy a new shaft at this point.


Have a look at these pictures. Not sure if they help cause I can't
tell your model.

http://www.globerubberworks.com/nav....cts_drivesaver

Evan Gatehouse

Thanks, that clearly and exactly answers my question. They are bolts
so I'm going to have to get enough clearance to pull them out.
Everything is so closely coupled here that I think they must have put
the shaft into the coupling after making it up or slid the engine back
and forth on the mounts. The only way I can get enough clearance to
undo this is to cut out the stuffing box hose and slide the stuffing
box back. Then, I'll really be committed to the project.

--

Roger Long

Looking at those pictures, the tolerances, and the pilots on the
Drivesavers, I'm having a hard time understanding why my propulsions
guru's dislike them so much. I suspect it may be more of an issue in
the high horsepower boats I've been dealing with than the typical
cruiser engine.

--

Roger Long

Http://home.maine.rr.com/rlma/Stride...htm#Drivesaver

It looks as though the bolts in the gear coupling are studs. Is this
the case or are they bolts with heads inserted through the drivesaver
before assembly? I haven't got much clearance to work with and may
have to sacrifice and replace the studs by twisting them out with vice
grips and then replacing. If they are bolts instead of studs, I'll be
in a pickle unless I cut out the stuffing box hose first. I'm not
sure I want to commit to the job this year unless I'm sure I'll be
able to get the shaft out of the coupling.

It doesn't look like much of a clearance problem. The nuts on the engine
side should be removable with a box end wrench and the ones on the shaft
side with the same, or a socket wrench. You'll have to get the shaft
rotated of course, not sure how easily that's done in a boat.

My plan is to get the Drivesaver out, insert something between the
coupling halves that just bears on the shaft, and then use through
bolts through the coupling to jack the shaft out. Much depends on
getting that rusty set screw out.

On the collar? If you release that set screw (bolt) you should be able to
slide it back along the shaft, but it sure does look like it'll be a tight
fit. Don't know, but once the collar's loose shouldn't the prop shaft slide
out? At least enough to clear the collar?

This was a fresh water boat so I
don't expect it to be quite as bad as it looks. I'm going to make a
dam around the screw with swimming pool epoxy and fill it with Liquid
Wrench for a few days first.

Heh, a friend of mine used to say "I hope the man that invented Liquid
Wrench died peacefully in his sleep at a ripe old age". Saved our asses
more than a few times as gear heads on his old Chevy.

"What goes up must come down" is about all I can contribute to your
dilemma.

If it went in, it should come out. It seems unlikely the PO who
installed it put the engine with tranny in after the shaft, the only
way I can see to make a difference in the situation as you've described
it.

However, different makers treat their systems differently. I was
offered a DS which didn't fit - and it seemed to be studs, of the sort
on an engine mount. However, the type which uses a fail-safe pair of
straps is definitely bolts in recesses for the heads based on some
nubs, rather than a fully solid material such as yours.

However, I'm baffled, given your prior assertions, that you don't
eliminate the issue by using a solid spacer, as I'm, based on your
scholarly treatise on the subject, going to do. It will have holes in
it through which the bolts pass (of course, you still have to get the
other out), making future exercises much less demanding. A cutting
wheel would have that out in short order, if you didn't need to save
it.

Pictures of what I didn't use and what I will (before polishing to
mirror, which can be seen later) are the first three in
http://justpickone.org/skip/gallery/...ar06&start=132
- the polished spacer is 6 pages further in.

Meanwhile, there's an interesting exposition/treatise on alignment by a
power boat specialist (who also has an interesting section on blisters,
but, I digress) at http://www.yachtsurvey.com/Alignment2.htm

And, back to your problem, can the stuffing box tube be slid aft on the
shaft tube to allow more movement?

L8R

Skip, off to finish the Vee LED rope lighting and then to replumbing
the head

Morgan 461 #2
SV Flying Pig KI4MPC
http://tinyurl.com/p7rb4 - NOTE:new URL! The vessel as Tehamana, as we
bought her

"Twenty years from now you will be more disappointed by the things you
didn't do than by the ones you did do. So throw off the bowlines. Sail
away from the safe harbor. Catch the trade winds in your sails.
Explore.
Dream. Discover." - Mark Twain

Skip Gundlach" wrote

However, I'm baffled, given your prior assertions, that you don't
eliminate the issue by using a solid spacer, as I'm, based on your
scholarly treatise on the subject, going to do.

Good point and touched on in a reply above. Worth expanding on.

I was reporting what the most knowledgeable driveline people I've met
told me. Looking at better pictures of the unit at the link that Evan
sent, I find it a bit harder to understand why they feel that way. My
discussions with them involved engines of 35 times the horsepower
which may bear significantly on the issue.

I still think my boat (and yours) would end up smoother with a solid
coupling and everything trued up as I recommend you do but it is
acceptably smooth to me now. I wouldn't at this stage of refit and
finances, pay for a spacer and all the other machining just to make it
a little quieter. I'll probably do all that before I head off to
Newfoundland in a few years but my priority now is to not find myself
sinking because the stuffing box hose let got while also avoiding
divorce because of the bills. Either would probably result in loss of
the boat.

I also have a wicked clearance issue that makes packing the stuffing
box almost impossible and would much rather invest in the proper
length shaft than a spacer. One thing prompting this is the discovery
that there is only room for one hose clamp on the stern tube. I think
it's long enough but someone lapped the glass on top too much and
covered up part of it. I think I can cut that back but I'll need a
new hose to get enough length for the second hose clamp. Sliding the
hose back enough to pull the coupling bolts is not an option.

--

Roger Long

Did you read the article on alignment I cited? It's by a primarily
high-end powerboat surveyor, so has that bias.

The best I can read out of his stuff is that alignment in our boats
isn't worth much...

Despite that, I''m still going to pull the tranny, the shaft, take off
the prop (of course, required) and take the couplings and shaft off for
truing, should it need it. Another list I'm on where a similar
discussion is taking place has it that the only reliable
truing/observation of a shaft is a calibrated roller bed. His (the
surveyor) article suggests it's not needed in our sizes, based on all
the other factors...

L8R

Skip

Morgan 461 #2
SV Flying Pig KI4MPC
http://tinyurl.com/p7rb4 - NOTE:new URL! The vessel as Tehamana, as we
bought her

"Twenty years from now you will be more disappointed by the things you
didn't do than by the ones you did do. So throw off the bowlines. Sail
away from the safe harbor. Catch the trade winds in your sails.
Explore.
Dream. Discover." - Mark Twain

I haven't had a chance to read it yet due to the rare opportunity to
actually earn a little money.

He may well be right. When I stop and think how stubborn and
difficult vibration issues are in high powered boats and how rare
problems are in almost universally neglected drive trains like ours, I
can believe it.

The shaft on one of my research vessels is about 3" dia. Three times
the diameter for over 30 times the horsepower so the relationships are
quite different.

You've got my curiosity up so I think I'll take a break....

You'll feel better after you do all that work anyway

--

Roger Long



"Skip Gundlach" wrote in message
oups.com...
Did you read the article on alignment I cited? It's by a primarily
high-end powerboat surveyor, so has that bias.

The best I can read out of his stuff is that alignment in our boats
isn't worth much...

Despite that, I''m still going to pull the tranny, the shaft, take
off
the prop (of course, required) and take the couplings and shaft off
for
truing, should it need it. Another list I'm on where a similar
discussion is taking place has it that the only reliable
truing/observation of a shaft is a calibrated roller bed. His (the
surveyor) article suggests it's not needed in our sizes, based on
all
the other factors...

L8R

Skip

Morgan 461 #2
SV Flying Pig KI4MPC
http://tinyurl.com/p7rb4 - NOTE:new URL! The vessel as Tehamana, as
we
bought her

"Twenty years from now you will be more disappointed by the things
you
didn't do than by the ones you did do. So throw off the bowlines.
Sail
away from the safe harbor. Catch the trade winds in your sails.
Explore.
Dream. Discover." - Mark Twain

Just skimmed it.

I think he's right but he's talking about something different than the
couplings faces being true and square to the shaft. If you have a
true running shaft pulled out of line by the engine moving on the
mounts or not being perfectly aimed towards the strut, that's one
thing and probably not a big issues as he says. If the engine is
trying to wave the far end of the shaft in a circle under the same
circumstances, I think you are going to have some noise.

--

Roger Long