I'm a new owner, and taking on a few projects that the survey had suggested ought to be done during winter haulout. After replacing the worn cutlass bearing (courtesy of the fabulous tool from the 36IA toolbox - yeah!), I moved on to tackle the shot engine mounts. Wasn't as bad a task as I imagined: undid the shaft coupling and the exhaust elbow, raised first one end of the engine and and then the other using a come-along suspended from a couple of 2x4s over the companionway, and slipped the new mounts in. The new mounts are the Vetus K75, and I took care to set each one at precisely the same height as the particular mount it was replacing. Thus, in theory the engine alignment should be close to what it was (which is not to say that it was correct, but its a good starting place).
However, because there is considerable play at the prop shaft -- i.e., with the coupling still separated, the free end of the shaft protruding from the stuffing box is unsupported and capable of vertical movement -- I'm not sure how to tell whether the bore alignment is correct in the vertical plane. Since the new cutlass bearing is snug, all the slop in the prop shaft is at the stuffing box end. As a result, its hard to tell whether the engine is too high or too low (the lateral alignment seems OK). Is the idea that one measures out the range of vertical movement and then wedge up (or suspend) the shaft up at the exact middle of that range, and then do the vertical bore alignment at the coupling? Or am I missing something here? Thoughts?
Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY
[url]http://www.c36ia.com/files/C36MkI_Owners_Manual.pdf[/url]
This is right on the C36 website see page 41, this should give you some info. Just my thought you do not want to crowd the shaft let it float between the cutlass bearing and the stuffing box (free wheel, so to speak). Try to allign shaft coupling to transmission coupling as close as possible by adjusing or moving the engine. Note the comment do not complete until boat in water.
Good luck!:D
Gary Bain
S/V "Gone With The Wind"
Catalina 36', Hull #: 1056, Year: 1990, Engine: M-35
Standard Rig
Moored: Boothbay Harbor, Maine
Home: Auburn, Maine
[QUOTE=Gary Bain;8169][url]http://www.c36ia.com/files/C36MkI_Owners_Manual.pdf[/url]
This is right on the C36 website see page 41, this should give you some info. Just my thought you do not want to crowd the shaft let it float between the cutlass bearing and the stuffing box (free wheel, so to speak). Try to allign shaft coupling to transmission coupling as close as possible by adjusing or moving the engine. Note the comment do not complete until boat in water.
Good luck!:D[/QUOTE]
Thanks, Gary.
Yes, I know, RTFM (Read the Friendly --or some other word of your choice -- Manual). But that doesn't quite answer my query.
Step 4 of the "Shaft Alignment" section of the Catalina owner's manual you pointed me to, on page 42, reads:
"Slide shaft forward to connect coupling surfaces. Pilot on transmission flange must align with recess in shaft coupling flange. This is an indication of axial alignment."
The term "axial alignment" is what I meant by "bore alignment" (the term used in Don Casey's book), as opposed to the face alignment (step 5). But what if there is not "an indication of axial alignment." If there were in fact a lack of axial alignment, obviously the engine as a whole must be raised or lowered (or shifted from side to side), as opposed to face alignment, the latter of which is more a matter of pivoting or swiveling the engine so that there is an equal .003" inch gap.
But how do we know if we have "axial alignment", if the unsupported flange end of the shaft has a capability of flopping around when unbolted (if for no other reason than the hose between the packing nut and the end of the fibreglass shaft lock is slightly flexible.)?
Mind you, I can definitely pull the coupling back together, and then do the face alignment to get the even .003 gap. But it seems to me that doesn't answer the question as to whether the shaft is properly centered in the packing and shaft log (I know I'm good as far as the cutlass end, since the new bearing allows no lateral or vertical movement at all). Do I check from beneath the hull, to make sure that the shaft is centered where it enters the shaft log? Or is this not so critical (as long as its not actually touching and abrading on the shaft log)?
Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY
Mat,
What kind of stuffing box do you have?
I can not picture how you could have that much movement at the shaft and have an effective seal on the stuffing box. If yours is a PPS style this may explain this, I have no knowledge of this type box
Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas
Matthew,
That's exactly what you should do. The end result should be the shaft snug in the cutless bearing (which it is), the shaft centered in the shaft tube, and the engine lined up with the shaft, in all directions. I assume your boat is on the hard, so some temporary wedges in the shaft tube (from the outside) should work well. Once the engine is close, you can take the wedges out and do the semi-final alignment. Once the boat is in the water for a few days, and the rigging tuned, then you can do the final alignment. Good luck with the new boat!
Tom Sokoloski
C36/375IA Past Commodore
Noank, CT
Thanks, all, for the quick feedback. One of the reasons I went with a boat with a large production was the value of a large users group. We had a Catalina 27 before, which also had a very active user group, so I've been delighted to find the great knowledge base for the C36 as I make this transition (a whole lot more to learn and maintain, of course).
Steve, I have the standard stuffing box design. Its not a ton of movement, so perhaps my use of the term "flopping around" was a bit of an exaggeration, but still enough movement to make me wary of just assuming that wherever the shaft is positioned "at rest" is necessarily centered in the shaft log.
Tom, when I checked today, I could see that the shaft was in fact lying on the bottom of the shaft log, at least where it exited below the boat, so I'm going to follow your suggestion and put a small wedge in there to support and center it. We'll then take it from there.
Another boat owner (not C36) at the yard today also suggested redoing the packing first, while I'm at it, which might help center it as well (the survey had recommended that I repack anyway), so maybe I'll do that in addition before doing the alignment.
Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY
Nigel Calder's book backs up your thoughts at to suspending the shaft at it's mid point of travel at the coupling end and aligning the engine to that axis.
_____________
Harold Baker
S/V Lucky Duck
Duncan Bay Boat Club
Cheboygan Michigan - Lake Huron
1989 C-36 mkI TR/WK M25XP
I was going to say that I would attempt to mark the position of the shaft at the coupling end at its extreme port/stbd and up/down locations, compute where the center is, and then temporarily fix the shaft at the center for the alignment work.
I would trust Calder's take on this, too.
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/