I have a 1980 Hunter 27 that sounds like a helocopter because of normal 1 cylinder diesel vibration. I can see that the shaft is not centered in my shaft log and is therefore not aligned properly. I would like to check to see if the shaft is bent and check the shaft log for damage before realigning. Do I have to drop the rudder to get the shaft out? I have paid three times to have the noise problem fixed all were unsuccessful and would like to try myself. Any help or past experiences will be appreciated. Thank you in advance; Pete Schaeffer SV Ilsa Marin Ocean City NJ
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Kevin l. Woody
Shaft location
Hello Pete, I wish I could advise you on whether the rudder needs dropped or not. I’m not familiar with the 27. It is not always an indication of a misalignment problem if the shaft is not centered in the stern tube. As long as the coupling halves are aligned and the stern bearing is aligned to the shaft its position to the tube is not critical. It does however become critical if the shaft is rubbing or making intermittent contact to the stern tube. This scenario could create a catastrophic failure to the tube and severe noise issues. The noise you are experiencing may simply be the one cylinder causing the system to jump. If you remove the shaft I would have not only shaft check for straightness but also have a fit and face done to the shaft and shaft coupling. This will insure that the coupling face is square to the shaft. Hope this helps. Kevin
Hello Pete, I wish I could advise you on whether the rudder needs dropped or not. I’m not familiar with the 27. It is not always an indication of a misalignment problem if the shaft is not centered in the stern tube. As long as the coupling halves are aligned and the stern bearing is aligned to the shaft its position to the tube is not critical. It does however become critical if the shaft is rubbing or making intermittent contact to the stern tube. This scenario could create a catastrophic failure to the tube and severe noise issues. The noise you are experiencing may simply be the one cylinder causing the system to jump. If you remove the shaft I would have not only shaft check for straightness but also have a fit and face done to the shaft and shaft coupling. This will insure that the coupling face is square to the shaft. Hope this helps. Kevin
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David Foster
Drop the rudder...
Anyway, that's what's required on my '77 h27. I had a quote from the survey report when we bought her. Haven't done it yet, because our thrumming vibration doesn't kick in until around 5 knots, and we are comfortable cruising below that speed when we use the iron Genny. (Our planning speed is 4 knots for cruising.) I don't believe you are talking about engine vibration from the wonderful one-banger - that's pretty easy to figure out. Do check the archives - there are some really good threads on this subject there. David
Anyway, that's what's required on my '77 h27. I had a quote from the survey report when we bought her. Haven't done it yet, because our thrumming vibration doesn't kick in until around 5 knots, and we are comfortable cruising below that speed when we use the iron Genny. (Our planning speed is 4 knots for cruising.) I don't believe you are talking about engine vibration from the wonderful one-banger - that's pretty easy to figure out. Do check the archives - there are some really good threads on this subject there. David
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R.W.Landau
Check the Motor mounts
Pete, Check the motor mounts and make sure that some of this is not the engine moving on the mounts. If you do decide to pull the shaft, it is a good time to check out all the rudder hardware. Pull the rudder, pull the shaft. Have the shaft checked and the propeller.Also check your cutless in the strut before you diassemble anything.Just shake the shaft and make sure there is no play. If there is, change the cutless. Someone, I can't remember who, used a bushing with the outside diameter about the same as the shaft log and an inside diameter of the shaft. Cut it lengthwise and slide it into the log. When you put the shaft back in the strut then through the bushing in the shaft log. Connect the shaft to the face plate. Then align the engine to the face plate. Pull the bushing and connect your stuffing box (packing gland). Your shaft will then be centered. This is far beyond what a yard would do. Good luck with your project. r.w.landau
Pete, Check the motor mounts and make sure that some of this is not the engine moving on the mounts. If you do decide to pull the shaft, it is a good time to check out all the rudder hardware. Pull the rudder, pull the shaft. Have the shaft checked and the propeller.Also check your cutless in the strut before you diassemble anything.Just shake the shaft and make sure there is no play. If there is, change the cutless. Someone, I can't remember who, used a bushing with the outside diameter about the same as the shaft log and an inside diameter of the shaft. Cut it lengthwise and slide it into the log. When you put the shaft back in the strut then through the bushing in the shaft log. Connect the shaft to the face plate. Then align the engine to the face plate. Pull the bushing and connect your stuffing box (packing gland). Your shaft will then be centered. This is far beyond what a yard would do. Good luck with your project. r.w.landau
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Garry Elmer
Aligning the shaft
Greetings! I just went through all of this on my 1980 33. My drive line was so far out of alignment that the bronze shaft was actually flexing and giving us that "African Queen" kind of sound. We replaced the shaft with S/S as I bent the threaded portion (story in itself). When I replaced the cutlass bearing I couldn't even turn the shaft. I aligned everything to the stern tube with an insert to hold the shaft straight while I aligned the strut to it. I have a description of what I did in the Cherubini area. I have only had it out once but it was smooth as silk, even full rudder throws at full speed. If you have any questions feel free to contact me. elmergw@99main.com http://www.99main.com/elmergw/
Greetings! I just went through all of this on my 1980 33. My drive line was so far out of alignment that the bronze shaft was actually flexing and giving us that "African Queen" kind of sound. We replaced the shaft with S/S as I bent the threaded portion (story in itself). When I replaced the cutlass bearing I couldn't even turn the shaft. I aligned everything to the stern tube with an insert to hold the shaft straight while I aligned the strut to it. I have a description of what I did in the Cherubini area. I have only had it out once but it was smooth as silk, even full rudder throws at full speed. If you have any questions feel free to contact me. elmergw@99main.com http://www.99main.com/elmergw/
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George Geary
Shaft Mis-alignment
Pete, When I purchasesd my 79', it needed a cutless bearing. Went to pull shaft: dropped rudder, but coupling would not release. Placed 2 X 4 across hatchway and used boom vang as hoist to lift engine out of way, removing shaft to bow, and to do work. It turned out to be fairly quick and straight forward. You only have mount bolts, fuel, 2 control lines and few electrical connections, coupling was all ready released. Anyway, the point here is that after purchasing a new shaft and installing new cutless, much to my surprise as I inserted the new shaft through the cutless to the shaft log, expecting it to hit at least close to the hole, it was almost 3/4 of the shaft diameter off. The final fix was to reset the strut. I removed the strut, opened up all the mounting holes to allow for adjustment, then dry fit everything, with moter reset in compartment. Actually had to put a slight twist in the strut to make things work. Finally, used 5200 to bed the strut and allowed set to occur with shaft in-place with multi-step tightening of the strut hardware, always checking rotational friction after each tightening. That was two years ago and she's still running smooth as silk (so to speak). I was not surprised that it needed a cutless when the original factory fit was so poor. Good Luck!
Pete, When I purchasesd my 79', it needed a cutless bearing. Went to pull shaft: dropped rudder, but coupling would not release. Placed 2 X 4 across hatchway and used boom vang as hoist to lift engine out of way, removing shaft to bow, and to do work. It turned out to be fairly quick and straight forward. You only have mount bolts, fuel, 2 control lines and few electrical connections, coupling was all ready released. Anyway, the point here is that after purchasing a new shaft and installing new cutless, much to my surprise as I inserted the new shaft through the cutless to the shaft log, expecting it to hit at least close to the hole, it was almost 3/4 of the shaft diameter off. The final fix was to reset the strut. I removed the strut, opened up all the mounting holes to allow for adjustment, then dry fit everything, with moter reset in compartment. Actually had to put a slight twist in the strut to make things work. Finally, used 5200 to bed the strut and allowed set to occur with shaft in-place with multi-step tightening of the strut hardware, always checking rotational friction after each tightening. That was two years ago and she's still running smooth as silk (so to speak). I was not surprised that it needed a cutless when the original factory fit was so poor. Good Luck!
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