2001 Grand Alaskan sea trial vibration issue..thoughts?

So we finally sea trialed with the surveyor the boat we have under contract. I really like this boat, and most traditional boats. My wife and friends call them the "Old Man and the Sea" Boats. The boat is well above average above the floors, but the bilge and engine room could use some work. But there were two things that I have troubled by.

1-There is a noticeable vibration at higher loads. So much so the flybridge Stidd chairs looked like those cheap vibrating chairs from the 70s you put a quarter in. This is really noticeable at full load with was about 18 knots. We ran it in the river, but later in deeper water where it was less noticeable, but still there. There was some discussion that it could be caused by swallower water, otherwise known as Squat Effect or Leonardo's Law, ergo the deeper water run to see if it would go away.

https://en.wikipedia.org/wiki/Squat_effect

2-It is loud, so loud that you could not enjoy the back deck under cruise. Loud is not always bad. Top Fuel be it on the water or strip, Formula One from the Schumacher days, or the Rotary Mazda Prototypes back in the day that made your ears bleed. But not so much with the wife and friends on the back deck at cruise. I get it, I know there are boats with underwater exhaust, pods, etc, and these are old school 3196s. All we needed were side launch torpedos and 20 more knots to be a PT Boat. But it was cool in a way, but could get old as well. It would be nice to find a way to quite it down some. I think the exhaust from the manifolds back or risers will need replacing, maybe something could be done then. I knew it would be loud when I noted the mufflers looked like the Cherry Bombs we ran back in the day. I hope there is a way to quieten it, but according to some of the old articles, maybe not?

What could be causing the vibration? I know about the typical thing. Although I have not seen the survey, our surveyor thinks the cutlass bearings are good, no noticeable prop issues, no motor mount issues. I did notice one rudder for some reason has a slight bend. The shafts and props where replaced in 18 I believe. The engines were rebuilt less the bottom end last year and have 240 hours on them since.

I have read, googled as far as I can go on vibration issues. Below is an email I sent to the surveyor today as a reference to this discussion:


Thank you for conducting the survey on Queen B, and it was a pleasure to meet you in this regard.

I have been "google" researching the vibration issue and of course have run across what you are considering or perhaps have ruled out. I look forward to you steering me in the right direction on this and I hope you will accept my apology if you find any of this offensive, but you don't strike me as that type.

Looking at the obvious, it only does it while running so it is either mechanical or as I think you or someone said said just a characteristic of the boat involving fluid dynamics. It also is very loud so I think someone even mentioned a resonating frequency could even cause this?

Let's also assume that if we ran it at those particular RMPs, there is no doubt it would be bad for the boat: fiberglass and gelcoat, but also electrical and finally the human factor of fatigue. I do realize of course the sellers and brokers could very well say, "Don't worry, you'll never run it at that rpm or speed." But of course we will on occasion clear the engines, outrun weather, or meet a schedule. It will also come up in any resale and who knows how that would be presented. I do know it would never be presented in a good light.

I assume your survey will include this vibration in your report, and I assume you will note the rpm settings where this was particularly noticeable. It did seem to be less in deeper water, but of course was still there, so the issue was not absolved by this change alone.

So let me ask the following: Google and the forums say it can be engine alignment, shaft alignment, bent or worn shaft, worn cuttles bearings, worn rudder stuffing boxes, out of balance or bent props, or motor mounts. Were you able to completely rule out all of those items?

Is it possible, since all was changed but the lower parts of the diesel that something is out of balance on the engine that the eye cannot detect like a crank? I know you looked at it and put your hand on it. Were you in the engine room when this was occuring? I think you were. I'm sure this was not the cause but I am trying to find out what was causing this. Consider this is a stupid question as I am totally ignorant on this and not an expert as you are.

I noted this in the brokers description:

• STAINLESS STEEL 2.5” PROPELLER SHAFTS (NEW 2018) WITH 4 BLADE NIBRAL 34” X 27” PROPS (DYNAMICALLY BALANCED 2021)
• SPARE PROPELLER SET IN AFT LAZARETTE IN TEAK CRATES
• DRIPLESS SHAFT SEALS WITH SPARE SEALS INSTALLED (NEW 2018)
• LINE CUTTERS ON PROPELLER SHAFTS. (NEW 2018)

I took the liberty to go three houses over and speak to the owner of the 63 Outer Reef cockpit motoryacht once we were back at the dock, as I have been considering one in Oxnard, CA. They only made three of these, so it was amazing to see this as I have been wanting to see the layout. I told him about the vibration on the flybridge and this is what he told me. He had the same issue, he kept replacing the cutless bearings. Then they discovered that the line cutters were cutting off flow from them, and he had them removed. He never had an issue since. I noted in the broker description that Queen B has line cutters.

If it is none of the above mechanical and just the characteristics of this boat, someone in the past should be able to verify this, such as the former owner, surveyor or Gary Oviatt with whom I have been able to contact but not really speak with at this time.

As for the exhaust, my god was that loud. I know one of the joys of having a boat like this is sitting on the back deck while you enjoy the cruise. That would not be possible without damaging your ears further. We already are experiencing this as we age.

I know the engine room needs work including the following:

1-Replace the entire exhaust system. When this is done, do they make any type of muffler or would that restrict the diesels too much, reducing their life? Underwater exhaust would be best, but that has its own risk from what I have been told and would be even more expensive if it could even be done. I remember the old cruisers back in the day even mounted something at the end of the exhaust off the stern to push it under water.

2-Change all hoses that were not changed when the engine work was done. Did you ask to see the records and service history? If not, can you go back to review these? I am, however , assuming you did? I was amazed at the neet filing and amount of records Charlie has under the pilot house settee.

3-Tydy up the wiring (I had previously noted loose wiring that had been added, disconnected, etc over the life of the boat that could be run better or at least made much neater.

4-The tops of the fuel tanks looked like they were never cleaned, wiped, and had miscellaneous items that did not belong there. Could you tell by looking at the tops that they were iron, or was that also enclosed? I do not recall.

5-Clean and paint the bilge and all surrounding areas.

6-It is time for bottom paint and zincs.

7-The rudder is bent. I assume there is no way something this insignifiant could cause this vibration. I know in the brokers description you can find here, it says the shafts were replaced. Why?

What I will do is talk to the former owner, and I might try to call the previous surveyor, or perhaps you should do this as they should regard you as a peer and therefore answer your question on the vibration out of professional courtesy? My question is did they note a moderate to what I would call severe vibration at the higher RPMs?

Thank you for your professional service regarding this matter. You come highly recommended, and I look forward to fully reviewing your final report.

Best Regards,


I know that was long winded, but any prior experience or advice would be appreciated. What I don't want to do is purchase this boat and spend thousands, maybe tens of thousands chasing a problem that cannot be solved. I am guessing most yards will want to start replacing things, like cutlass bearings and go from there. At least that is my past experience. I like this boat, these are hard to find in this condition, but I don't intend to make an avoidable mistake.

Thanks forum....



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Thanks guys for the input, that's why I like this forum. One would think with the bent rudder it did run aground or it sat on something somewhere sometime in its past. As for the shaft I agree that's a lot of unsupported shaft but then again I am not an engineer.

He did stop and while he was in the engine room shift forward and reverse then advance the throttle to check the beds and mounts.

I hope he did register the decibels as it would be interesting to know just how loud it is.

Do you know if they make any kind of underwater exhaust that is a bolt on? I think I recall something in the past, but if it was possible I assume a simple google search would have shown it.

As for the build quality I have read that in a couple of forms and postings on the internet, and was told it depended on the yard. I have been told this one was built in the same yard as Outer Reef, but of course, it is not an Outer Reef.

I know there original owner went over to inspect it and followed his build closely since I tracked him down and spoke with him about it. I do like that he was a long term owner and used and maintained the boat, keeping it in heated storage for 8 months out of the year in Syracuse but still using it enough to accumulate 2600 hours. When it was purchased the original owner agreed to have the work done on the engines, and that the new owner have put 240 hours on it since this work. Here is the write up from Yachtworld.

Owners Note:

When purchasing this vessel in early 2021 we retained the services of a Caterpillar factory trained and certified technician. The engines ran great but a check of the factory records revealed that when the engines were new a factory recall to upgrade the after coolers was missed by the owner. A careful examination revealed minor pitting. As a result, the seller agreed to a COMPLETE Caterpillar rebuild of both engines. All work was done by our Caterpillar certified technician using ALL Caterpillar parts.

Work included:

• New upgraded aftercooler assemblies
• New factory built complete head assemblies (head, valves etc)
• New factory built complete cylinder assemblies (sleeves, pistons, rods etc)

In addition, while the engines were disassembled we decided to also:

• Replace all injectors with new Caterpillar injectors
• Have all heat exchangers removed, cleaned and reinstalled
• Have both raw water pumps rebuilt
• Replace hoses and belts

The bottom line: With the exception of the after coolers, none of this work was actually required. However, new owners going forward will have peace of mind knowing that both engines are as close to factory fresh as possible. It's reasonable to expect many years of reliable service.

https://www.**************/yacht/2001-grand-alaskan-raised-pilothouse-8156584/

As for Outer Reef we've been looking at them for some time and really like them. They are on the radar.

The Vibration and noise are defiantly an issue. The ordinal owner who had it built and visited the yard several times while under construction sure kept it for a long time. I do like the long term storage he had but still used it. I need to find out again his reasons for replacing he shafts and props. Seems I recall him saying something about they had some wear. Like you, I look at evidence, like the bent rudder and vibration. And who knows, maybe the couple that own it now never took it up on plane. But walking is an option that's for sure. I know, don't fall in love with any boat, and really the most important part is below the cabin if you plan to use it for more than just a condo.

Yes about the planning it was bow high positon. I have made contact with a broker who work for Oviatt and sold these new, a delightful lady. She has been kind enough to answer my questions about the build, vibrations, and noise. She said the vibration defiantly is not a characteristic of this boat (someone said it could be so I asked her-of course I did not think so) and she also said it should not be as loud as I described. She was wondering as well about all of the things discussed, cutlass bearing, props, motor mounts, etc. I guess I will wait for my surveyors report. Has anyone used Noel Miley https://floridamarinesurveyors.us?

The broker who was with Oviatt told me a funny story and it relates to the fact that these engines are interesting choices for what is a more displacement than semi displacement boat. She said that Art Defever was on board during a sea trial where they were built and they were going through the paces. When the put it under full load and hit 18 knots she looked at Art and said, "Art I bet you didn't expect that did you?" Art said, "No, but it sure is fun!" It rode high bow at that speed, and that's where the worse vibration occurred. At the regular cruising speed it was not as noticeable.