All three mounts are not identical, since the front one carries more weight than the rear ones - this is why Westerbeke has different part numbers for them. I replaced mine last spring with the following part numbers.
The rear ones were relatively painless using a board to distribute the weight to the hull, and a small scissor jack on the bock/transmission joint, being careful to avoid the oil pan flange. I also used a strap and a 4:1 purchase with a cam cleat rigged to a board across the top of the companionway opening for safety.
The front was a real challenge to figure out, since the supporting yoke between the stringers for the single mount interferes with lifting from below. My solution was to rig a loop completely around the engine (again, avoid the oil pan…) with a 1000 lb nylon lifting strap, and then lift that from above with a ratcheting tie down strap rigged in a loop through both lazarette openings and the engine loop. If you do this, cut a board to fit across the cockpit between the lazarette boards to support the compression load from the ratchet strap to avoid any damage.
Then the real fun begins - getting the perfect engine alignment…
A reply from Tim is missing But my front (of engine) mount is done and the hardware that holds the rear of engine mounts is undone. I did not have to take the heat exchanger off to do any of this but did remove the sea water discharge hose from it. My latest dilemma is getting the starboard side mount out of the ear on the engine casting. There is enough room around the port side mount that I was able to grab it with large channel locks and this it but I do not have the room on the starboard side. I have been soaking it with PB Blaster and Liquid Wrench and will beat it with a hammer some more tomorrow. If this doesn’t work I will try pressing it out with a small gear puller but space remains the issue. Of all the mounts this mount and the angle iron under it are the ones that need the most attention.
Tim, how are you making out with prop alignment? You said you aligned the shaft with it centered in the shaft log. What consideration does the cutlass bearing get in this procedure?
Regards,
Bill Mortensen
1986 NS 30U #335
Summer Song
Noank, CT
A friend lent me Nigel Calder’s Boatowner’s Mechanical and Electrical Manual and he answered my question thusly:
Checking and adjusting engine alignment.
To check alignment, undo the coupling bolts and separate the coupling halves. In cases where a long run of propeller shaft is unsupported by a bearing, the shaft will sag down under its own weight and the weight of its coupling half. In this case, the correct procedure is to calculate half the weight of the protruding shaft, add to it the weight of the coupling, and then pull up on the shaft by this amount with a spring scale of the type used for weighing fish (Figure 9-21). In practice, smaller shafts can generally be flexed up and down by hand to get a pretty good idea of the centerpoint, and then supported with an appropriately sized block of wood. A notch in the wood will hold the shaft and allow it to be rotated.
There should be a machined step on one coupling that fits closely into a recess on the other. Bring the two halves back together- the step should slip into the recess cleanly and without snagging at any point. If it does not, the shafts.
Obviously there was more but this is the gist of it. Remembering yo before I took it apart I think I will forgo the fish scale part but just because it’s here in my garage I will weigh the shaft.
Regards,
Bill Mortensen
1986 NS 30U #335
Summer Song
Noank, CT
I didn’t have much trouble getting them free of the engine mounting holes, but I would maybe try jamming two nuts together on the threads, and then try to rotate it with a wrench, cw on the top nut, and ccw on the bottom one. A hammer may damage the threads, eliminating this as an option.
On the alignment question, I assumed the P bracket with the cutless bearing was aligned with the shaft log when the boat was built, and the cutless bearing has some tolerance to a less than perfect alignment. I did the initial alignment with the prop and packing gland removed, and the shaft wedged in the center of the shaft log. After the shaft coupling and transmission flange were concentric, and the pilot diameter went in easily, I removed the wedges and fine tuned the gap between them. Then removed the shaft, and reinstalled with the packing gland on the shaft only, then slide the packing gland down the shaft onto the shaft log with a little waterproof grease. In summary, align the shaft to the log, the engine to the shaft, and then the packing gland should naturally end up aligned to both the shaft and the log. Reinstall the prop, launch the boat, double check the alignment with it floating, fasten and safety wire the coupling - done.
My thought was that the cutlass bearing location was more important than the log because it doesn’t seem to me that the log can be installed that accurately and that’s why the packing box hose is there but I do not know how the log location is determined. How was cutlass bearing alignment when you put it all back together? I’m putting the rear engine mounts (towards front of boat) back in tomorrow. I’ll center the shaft in the log and see how it all looks.
I wasn’t worried about damaging the threads on the mount as I was replacing it anyway but as it was the threads were okay. I am including a picture that shows how tight the area it is but the picture does not really do the space justice. The shiny spot on the mount is where I was beating on it.
I can’t say for sure how the boat was constructed, but by my math the maximum movement of the shaft in the log is only about 1/2" from touching one side to the opposite, which over the distance between the log and bearing is less than one degree. Considering this, the boat should be built with them aligned from the beginning. I think the right way would be to glass the log in, then mount the P bracket with a shaft going through the cutless bearing and wedged in the center of the log. My shaft appeared to be parallel to the cutless bearing, but in any case, the bearing is rubber and has some compliance. Worst case you would have a small amount of initial wear on the bearing, followed by a long service life.
Tim,
After having spent too much time obsessing on this I concluded that the boss the log goes through is moulded in when the hull is laid up and then a fixture is used to drill for the log and P bracket at the same time ensuring they are li9ned up. I’ll see how it goes, my mounts are all installed and now the line up process begins.
Yes, the point of my previous post is, you can’t move the shaft far enough within the log to significantly change its alignment to the bearing. Just center the shaft in the log and go from there. The other reason you want the shaft centered in the log, is there isn’t a lot of clearance between the shaft and the ID of the packing gland, so if they are not parallel to each other, the shaft will rub on the bronze.
Our transmission is out for work and I picked it up from the shop yesterday to deliver to the yard for install. I plan on new engine mounts - the transmission rebuild guy stated that engine mounts have a service life of . . . . 5 years! Ours are only 36 so I guess we got good service out of them (and they have probably been causing our tranny problems for years).
While the tranny is out, we are also putting in a new bellows for the PSS dripless stuffing box - which has a service life of like 6 years. Ours is over-due.
Lloyd,
All I have left to do for my mount replacement is the prop shaft alignment. I believe my mounts were original and they didn’t look as bad as I expected, the big problem is a washer that had a load on it had apparently dissolved. The angle iron that they were bolted to certainly needed cleaning up and replacing. I originally was thinking I would take the transmission out to replace the mounts and Joe V. suggested if I was going to do that I should replace the drive plate. I did research into the drive plate and found that Sachs 1866-061-001 is a replacement for Westerbeke 19398. it is 1/3 the price from https://www.fredwarner.net. about $350 instead of $1250!
Regards,
Bill Mortensen
Summer Song #335, N30U
Noank, CT
On Friday, April 14, 2023 at 3:03:54 PM UTC-4 Julie & Lloyd on Rendezvous wrote:
