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Old 08-11-2020, 05:03 PM   #21
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Since the props were tuned to Class I just 6 months ago, and absent any strikes, I'm not seeing a lot of value in tuning them again. Though if there is time, I suppose a quick scan couldn't hurt.
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Old 08-11-2020, 05:22 PM   #22
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Since the props were tuned to Class I just 6 months ago, and absent any strikes, I'm not seeing a lot of value in tuning them again. Though if there is time, I suppose a quick scan couldn't hurt.
They are only class 1 when they reenter the water. One does not always feel the bumps which can make them otherwise. Trying to resolve vibration during a haul seems like the right time to remove all doubts about each and every item in the drive train and waste of time and money not to do so.
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Old 08-11-2020, 06:47 PM   #23
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Since the props were tuned to Class I just 6 months ago, and absent any strikes, I'm not seeing a lot of value in tuning them again. Though if there is time, I suppose a quick scan couldn't hurt.
Class 1 is probably as good as the average prop shop will get.
Wonder if the props were lapped to the shafts when installed?
You could chase alignment issues forever and then discover a transmission gear is worn and only shows up at certain rpm.

I'm happy as long as forward and reverse work.
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Old 08-11-2020, 07:35 PM   #24
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They are only class 1 when they reenter the water. One does not always feel the bumps which can make them otherwise. Trying to resolve vibration during a haul seems like the right time to remove all doubts about each and every item in the drive train and waste of time and money not to do so.

I think you are right. Penny wise and pound foolish.
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Old 08-11-2020, 08:55 PM   #25
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The shop I took mine to scanned them for free, so why not scan them again. Mine each had one blade way off the others. Had them repitched down 1/2” and trued up. $800 for each prop.
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Old 08-11-2020, 10:40 PM   #26
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The props were just tuned and are Class I. We're verifying that of course, but I doubt they have changed in the last 4-6 weeks.

We did inspect the motor mounts and they do have rubber under the bells. I don't know why I assumed they didn't. This is my 7th boat and I've changed these before. I will chalk it up to living on land the last 48 hours and very long days....

The motor mounts could potentially be original, but there is no way of knowing. I will definitely be replacing them later this year in the water. Doing it while I am out would be great, but we have enough other work already scheduled, and all of the local yards and people are super busy, so trying to do it now would add at least a week if not two on a 2 week stay already.

Shafts are out and look great, no damage, no other problems found.

Based on process of elimination so far, the vibration is either coming from being out of alignment or the engine mounts (or both of course). We'll be replacing the failed shaft seals, getting everything back together, and do a good engine alignment after the boat sits in the water a few days, which likely has not been done in a long time.

That should reduce the vibrations, and then later this year I'll replace the motor mounts and do another alignment.
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Old 08-11-2020, 10:43 PM   #27
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Since the props were tuned to Class I just 6 months ago, and absent any strikes, I'm not seeing a lot of value in tuning them again. Though if there is time, I suppose a quick scan couldn't hurt.
6 *weeks* ago, not months.

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The shop I took mine to scanned them for free, so why not scan them again. Mine each had one blade way off the others. Had them repitched down 1/2” and trued up. $800 for each prop.
They are being re-scanned, but we don't expect any issues there. If for some reason they are out of whack after 6 weeks then what am I running over!
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Old 08-12-2020, 09:09 AM   #28
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Are you sure the cutless bearings in the hull are not worn? Speaking from experience there is considerable sag/ bending/droop over the length of those long shafts. That can give you incorrect alignment readings at the face of the coupling flanges. And if the front and middle bearings are worn, there’s potential for shaft “whip” under some conditions. If the 42 is the same as the 44, now is the time to replace all of them. That said, the OA yard in Seattle told me they sometimes skip the one by the stuffing box, but then they compensate for the sag at that end when doing the alignment. Not clear who’s doing the work, but checking with the OA yard might be worth the call.
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Old 08-12-2020, 09:37 AM   #29
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Everything has been pointed out to you that could be wrong. You can follow your time frame and splash the boat before every vibration point can be addressed. BUT everyone here is advising against it. In 25 years, I've seen plenty of people delay a bottom job to accommodate their schedule, no danger of further damage. Just delay the haul lout until you have time to do it right. No boating over trawler speed until it's fixed properly. I have a feeling you have a boating trip planned and won't admit that's why you're in a time crunch. You know we'll all tell you to delay the trip. I Hope I'm wrong.
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Old 08-12-2020, 10:32 AM   #30
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This thread got me to thinking about how to gauge if and whether there is an improvement based on the work done. I recently downloaded an app for measuring sound and have been using it as I work on soundproofing the engine room. I took Db readings at low and high rpm with engine hatch off, hatch on, rug covering, first improvement, etc. Changes are slight but verifiable.

So what if there was an app for vibration? Turns out that there is (are). I have no experience with them yet (and some reviewers claim that they contain spyware, just like your breakfast cereal box).

Place the phone in a standard location and get high/low rpm reading. Port engine, stbd engine, both (working on synchronization). Now, one would at least have a baseline when the future question of "did the vibration just increase?" issue arises.

One of the things I found with my sound meter app is that the Db reading at 1,500 rpm is basically the same as at a spot near 1,800 rpm. DB was rising (not entirely uniform) and then took a little dip. This might explain the mysterious "sweet spot" we tend to find on a certain motor.

Measuring vibration might also identify a plateau that we identify as a sweet spot in addition to having a vibration baseline.
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Old 08-12-2020, 10:46 AM   #31
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Everything has been pointed out to you that could be wrong. You can follow your time frame and splash the boat before every vibration point can be addressed. BUT everyone here is advising against it. In 25 years, I've seen plenty of people delay a bottom job to accommodate their schedule, no danger of further damage. Just delay the haul lout until you have time to do it right. No boating over trawler speed until it's fixed properly. I have a feeling you have a boating trip planned and won't admit that's why you're in a time crunch. You know we'll all tell you to delay the trip. I Hope I'm wrong.
You're hope came true. He clearly stated all the yards are booked and he would be forced to spend weeks in a hotel. He has followed the advice of just about everyone who has posted. Spending thousands to chase down a barely detectable vibration at X rpm doesn't strike me as a good use of his money.
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Old 08-12-2020, 11:46 AM   #32
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Thanks for pointing out my oversight/error/lack of thoroughness. I am glad to be wrong as to why.
I agree with your opinion about spending thousands on a barely detectable vibration. But it does seem the he wants to fix it, not sure about the money issue. But, if he's living aboard, it will still cost him more money if it needs to be hauled again. If the motor mounts get replaced later, in the water, won't he need to pull the boat to align the shafts? If that's true, maybe he should delay this haul until he addresses the motor mounts. Doing it in the proper order? Does this make sense to anyone besides me?
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Old 08-12-2020, 12:53 PM   #33
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Are you sure the cutless bearings in the hull are not worn? Speaking from experience there is considerable sag/ bending/droop over the length of those long shafts. That can give you incorrect alignment readings at the face of the coupling flanges. And if the front and middle bearings are worn, there’s potential for shaft “whip” under some conditions. If the 42 is the same as the 44, now is the time to replace all of them. That said, the OA yard in Seattle told me they sometimes skip the one by the stuffing box, but then they compensate for the sag at that end when doing the alignment. Not clear who’s doing the work, but checking with the OA yard might be worth the call.
That's a good point, and something we've discussed. The ones at the struts are in good condition from what we can see, as are the ones at the stuffing box. The ones in the strut are easy to remove with a press tool. The ones at the stuffing box are a pain in the ass, and many people do not replace them because of how difficult it is to get them out as long as they look good. I did talk to OA and that is one of the things they recommended, which sounds like they said the same thing to you!

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Everything has been pointed out to you that could be wrong. You can follow your time frame and splash the boat before every vibration point can be addressed. BUT everyone here is advising against it. In 25 years, I've seen plenty of people delay a bottom job to accommodate their schedule, no danger of further damage. Just delay the haul lout until you have time to do it right. No boating over trawler speed until it's fixed properly. I have a feeling you have a boating trip planned and won't admit that's why you're in a time crunch. You know we'll all tell you to delay the trip. I Hope I'm wrong.
I don't have a boating trip planned - no hard dates or schedules that are forcing me back in the water. I live aboard my boat, so staying out longer is extremely costly - I think I may have mentioned that somewhere. Plus, there simply isn't room or time for them to accommodate me longer. The yard I'm at is booked out until September 20th, packed so full I have never seen it that way, and they just can't keep adding jobs on without having the boat physically sit for a very long time with no work until someone is available.

My day job is managing complex projects with constantly changing risk. In most situations with yards, I see owners drop a boat off and check in every few days, maybe less. In this situation, I'm 100% focused on the work that needs to be done out of the water, and help refocus them since I am there every day. Replacing the engine mounts is a great example. That needs to be done, but it does not have to be done out of the water. If we get the important things done out of the water, I can continue doing other things dockside or at a later date to improve things.

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This thread got me to thinking about how to gauge if and whether there is an improvement based on the work done. I recently downloaded an app for measuring sound and have been using it as I work on soundproofing the engine room. I took Db readings at low and high rpm with engine hatch off, hatch on, rug covering, first improvement, etc. Changes are slight but verifiable.

Measuring vibration might also identify a plateau that we identify as a sweet spot in addition to having a vibration baseline.
Hey this is cool! Thanks for posting this. Some of my concerns about the vibrations I am sure are heightened because of the issues I've gone through, and very well may be no worse than it has been for 2 years! But instead of my subjective standing over the areas and moving around while underway, it would be awesome to be able to measure it. I'll have to look into this once I'm back in the water.

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Thanks for pointing out my oversight/error/lack of thoroughness. I am glad to be wrong as to why.
I agree with your opinion about spending thousands on a barely detectable vibration. But it does seem the he wants to fix it, not sure about the money issue. But, if he's living aboard, it will still cost him more money if it needs to be hauled again. If the motor mounts get replaced later, in the water, won't he need to pull the boat to align the shafts? If that's true, maybe he should delay this haul until he addresses the motor mounts. Doing it in the proper order? Does this make sense to anyone besides me?
I definitely would like to fix the issue, but I am not willing to spend "anything" to do that. I look at each problem and review with the experts (which includes folks here, folks online, and the yard) what their best recommendations are for the particular problem or section, and weigh how much the work will potentially change the situation compared to the cost. I know some people who will spend anything and replace everything, regardless of the time or cost, and that is a great approach as well, if you can afford both the time and cost. In some ways you may be spending money to replace things or have work done with that approach when you didn't need to. I don't think I'm skipping any steps or areas that have been identified, or not looking at any specific areas - we're trying to make sure we track down everything possible to solve the issue, but of course, it is a boat, so some mysteries take longer to understand than others.

When you replace the motor mounts, you will need to do a new engine + shaft alignment, which has to be done in the water. The shape of the hull changes dramatically when it is out on the hard, and you cannot align it until the boat is back in the water and has settled for multiple days.

That's one of the reasons I've deferred that work for now - the other reason is the yard is so busy they don't have time to replace them right now. But they can do it in October dockside, without a haul out, and do another alignment then, which seems like a great way to get it done without sitting in the yard for 6-8 weeks.
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Old 08-12-2020, 12:55 PM   #34
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Shafts are aligned in the water, so replacing the mounts in the water is the way to go.
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Old 08-12-2020, 01:13 PM   #35
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I've never had to do a shaft alignment. Now I know better and it also makes sense to me why Steve is following his path. Steve, I want to thank you for addressing several suggestions brought up and a clear explanation of how you thought things through. It all makes sense to me now. Hoping things go smoothly for you now and in a few months when you finish the work!
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Old 08-12-2020, 02:41 PM   #36
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You mention the bearings at the stuffing box and the one at the strut, but not clear if the one that exits the hull is within spec....also a big PITA to remove, but pretty critical... I drove it out of the shaft tunnel with a piece of pipe (inserted from the engine room end) and a BFH. The set screws were difficult to locate with all the bottom paint..,
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Old 08-12-2020, 03:13 PM   #37
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I've never had to do a shaft alignment. Now I know better and it also makes sense to me why Steve is following his path. Steve, I want to thank you for addressing several suggestions brought up and a clear explanation of how you thought things through. It all makes sense to me now. Hoping things go smoothly for you now and in a few months when you finish the work!
I've done my own shaft alignments on sailboats which were much smaller, and seemed simpler to me to do in the past. That was a number of years ago, and it took a lot of trial and error to get it right.

Now I let the professionals do it because they know the tricks and how to make something move somewhere easier than I do. I'll still be aboard and watching while they do so I can learn, and watch that the work is done to my expectations, but they are also generally far more flexible than I am to fit into the spaces needed. The guy who will be overseeing it has done it for 15+ years and has done it for me before on a previous boat without any issues.

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You mention the bearings at the stuffing box and the one at the strut, but not clear if the one that exits the hull is within spec....also a big PITA to remove, but pretty critical... I drove it out of the shaft tunnel with a piece of pipe (inserted from the engine room end) and a BFH. The set screws were difficult to locate with all the bottom paint..,
I can see the set screws for everything which is nice. The traditional way I've been told they remove the bearing that exits the hull is using a sawzall and patience. Cutting it in two spots, folding it up, and removing it. Trying to pound it out from inside is an option but can be very tight - my little hatches to get to that spot are about 10" square, and it would be extremely difficult for one side to be pounded out, if it is even possible.

The stuffing boxes are being replaced, so that bearing will be new. The one that exits the hull looks good from inspection so far, as do the ones in the struts. It is still on the table to replace those as well depending on all of the other work being done. With the shafts out, it would of course be a good time to replace them. They actually look pretty new and are in excellent shape, so guessing they have been replaced in the last 5 years or even less.
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Old 08-12-2020, 03:48 PM   #38
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I’m sure it depends on the location of the transmission, but on our boat I was able to slide a four or five foot length of pipe/steel rod in from inside the engine room (in the vicinity of the coupling. They were both fairly easy to drive out. In fact the new ones, which I placed in a freezer over night kept sliding out (I had coated them with dish soap). So the fit isn’t that tight. I’d try driving it out before resorting to the sawzall method. Maybe even a big slide hammer with a custom hook.

By the way, the bearing just behind the stuffing box is the one OA suggested could be omitted. It has nothing to do with changing the stuffing box on our 44.
Good idea to change it, but the hull exit ones are about mid span on our boat.
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Old 08-12-2020, 04:04 PM   #39
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I’m sure it depends on the location of the transmission, but on our boat I was able to slide a four or five foot length of pipe/steel rod in from inside the engine room (in the vicinity of the coupling. They were both fairly easy to drive out. In fact the new ones, which I placed in a freezer over night kept sliding out (I had coated them with dish soap). So the fit isn’t that tight. I’d try driving it out before resorting to the sawzall method. Maybe even a big slide hammer with a custom hook.

By the way, the bearing just behind the stuffing box is the one OA suggested omitting from renewal. It has nothing to do with changing the stuffing box on our 44.
Sounds like a good way to do it. I've heard the freezer trick before, and I have used lots of dish soap myself. The yard uses it in gallon sizes

Ok, so just to clarify: the bearing that is directly exposed to the outside and is visible from outside that the shaft goes through is the one you replaced? There's another one (composite I believe you said) behind the packing but inside the stuffing box that you did not replace, and OA says to not worry about?
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Old 08-12-2020, 06:56 PM   #40
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Shafts are aligned in the water, so replacing the mounts in the water is the way to go.
We had an engine and transmission out last winter. After I put it back in we did an engine alignment before we launched. I had thought we would have to do another alignment after we launched. However it was still exactly the same after several days when we checked it after launching. I guess they had the boat blocked almost perfectly when we did the alignment. I was surprised.
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