Greeting all, Slight vibration (other than the normal vibrations)is felt on the cockpit sole while motoring, diving prop shaft reveals slight (1/8 - 1/4"?) horizontal play at prop center, no verticle play was found. I assume this means the cutlas bearing is going? Could somebody please tell me I don't have to pull the boat and drop the rudder to replace? Thanks, Ken
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Me too
Ken I think I have the same problem.OK, you have the normal vibration from the diesal.Then at high rpm there is a stronger vibration that has a tempo about every 10 seconds.throdle back and it goes away.I think it could be a bearing, and or just too much rpm.We do have a max hull speed.Any more rpm and it could be overkill on the drive system,and the vibration is the result.I'm not sure.I just got her, and did the first trip from pencicola to ft. walton,where she will be renovated.[1979HUNTER CUTTER RIG Yanmar engine hearth transmition]If you have any input at all please email me back atjskaptain@hotmail.com
Ken I think I have the same problem.OK, you have the normal vibration from the diesal.Then at high rpm there is a stronger vibration that has a tempo about every 10 seconds.throdle back and it goes away.I think it could be a bearing, and or just too much rpm.We do have a max hull speed.Any more rpm and it could be overkill on the drive system,and the vibration is the result.I'm not sure.I just got her, and did the first trip from pencicola to ft. walton,where she will be renovated.[1979HUNTER CUTTER RIG Yanmar engine hearth transmition]If you have any input at all please email me back atjskaptain@hotmail.com
Cutlass bearing
1/8 inch is the maximum acceptable shaft play for the shaft bearing in the strut. I recommend you have her hauled, and replace the bearing. The whole operation should be in the few hundred dollar category. It's probably also a good idea to check the engine mounts and shaft alignment while you are at it. A problem there could cause increased vibration, and the cutlass wear you have observed. David Lady Lillie
1/8 inch is the maximum acceptable shaft play for the shaft bearing in the strut. I recommend you have her hauled, and replace the bearing. The whole operation should be in the few hundred dollar category. It's probably also a good idea to check the engine mounts and shaft alignment while you are at it. A problem there could cause increased vibration, and the cutlass wear you have observed. David Lady Lillie
cutlass bearing replacment
Ken, Good news is you don't have to drop the rudder and pull shaft to replace the cutlass bearing.There is a tool (see link) that will remove and replace the bearing with the shaft in place.You will have to remove the prop.You will still have to pull the boat.Most yards have (or should have) this tool. Good Luck !
Ken, Good news is you don't have to drop the rudder and pull shaft to replace the cutlass bearing.There is a tool (see link) that will remove and replace the bearing with the shaft in place.You will have to remove the prop.You will still have to pull the boat.Most yards have (or should have) this tool. Good Luck !
haul it
I've heard of others who have pulled the cutlas while in the water but I'm simply not that brave and I don't think I have that kind of knowledge base for that kind of stuff. As for the vibration, I had one on my boat. The shaft, cutlass and mounts were fine. The vibration turned out to be the shaft vibrating against the sides of the stern tube itself, my great mechanic (Ha Ha Ha) had the entire engine so far out of alignment that the shaft was hitting the tube causing one hell of a vibration. I finally diagnosed this by holding the shaft (while in neutral!!) and the shaking stopped. Good luck, I know how irritating it can be.
I've heard of others who have pulled the cutlas while in the water but I'm simply not that brave and I don't think I have that kind of knowledge base for that kind of stuff. As for the vibration, I had one on my boat. The shaft, cutlass and mounts were fine. The vibration turned out to be the shaft vibrating against the sides of the stern tube itself, my great mechanic (Ha Ha Ha) had the entire engine so far out of alignment that the shaft was hitting the tube causing one hell of a vibration. I finally diagnosed this by holding the shaft (while in neutral!!) and the shaking stopped. Good luck, I know how irritating it can be.
Lotta play
I have an H-37c which has been out of the water for a couple of weeks, and I last checked the prop shaft play just a few hours ago before launch. A quarter of inch is a lot of play, and I'd probably haul the boat to check it out. You've probably already checked, but you may want to make sure the problem isn't that the strut has loosened up a bit (which would produce lateral play). That can be tightened up with the boat in the water.
I have an H-37c which has been out of the water for a couple of weeks, and I last checked the prop shaft play just a few hours ago before launch. A quarter of inch is a lot of play, and I'd probably haul the boat to check it out. You've probably already checked, but you may want to make sure the problem isn't that the strut has loosened up a bit (which would produce lateral play). That can be tightened up with the boat in the water.
Thanks
Thanks for the input, I'll check the strut tightness and motor mounts again before hualing her. Was planning on leaving for Cuba next week, but will hold off abit. Thanks again, Ken
Thanks for the input, I'll check the strut tightness and motor mounts again before hualing her. Was planning on leaving for Cuba next week, but will hold off abit. Thanks again, Ken
for Steven F.
Steven: you mentioned your vibration problem was shaft against the stern tube. Were you able to resolve this problem? How did you go about it? thanks
Steven: you mentioned your vibration problem was shaft against the stern tube. Were you able to resolve this problem? How did you go about it? thanks
Jack, I know how. . .
I would align it. The boat would have to come out because I would disassemble the stuffing box. I would disconnect from the tranny and move it back a fraction. Then I would use spacers around the shaft to center it in the shaft log(stern tube). Have someone turn it slowly from the prop end while you are inside watching. It should turn freely in the cutlass bearing and you should see no wobble. This is to make sure the shaft is straight and that the strut is aligned with the shaft log. Actually if you get to this point you may as well pull the shaft, replace the bearing, and check for straightness. The point is that you will align the engine to a shaft already centered in the stern tube. If the strut and bearing do not line up with the stern tube that's a bigger problem.
I would align it. The boat would have to come out because I would disassemble the stuffing box. I would disconnect from the tranny and move it back a fraction. Then I would use spacers around the shaft to center it in the shaft log(stern tube). Have someone turn it slowly from the prop end while you are inside watching. It should turn freely in the cutlass bearing and you should see no wobble. This is to make sure the shaft is straight and that the strut is aligned with the shaft log. Actually if you get to this point you may as well pull the shaft, replace the bearing, and check for straightness. The point is that you will align the engine to a shaft already centered in the stern tube. If the strut and bearing do not line up with the stern tube that's a bigger problem.
just tossed money at it
Just kidding, wish I had that option. I have a machanic who I trust now. He came out and in two hours had everything aligned fairly well. I still have that vibration during 1100-1200 RPM range and very light at the RPM's just above my crusing range 1900-2200. Other than that it seems to be good. During the next haulout the shaft is coming out to be checked. Don't know if I mentioned this but the cutlass bearing, mounts are less than 18 months old. Once we confirm that the shaft is true we will go at it from back to front and make all right in my boating world for a short time until the next thing breaks.
Just kidding, wish I had that option. I have a machanic who I trust now. He came out and in two hours had everything aligned fairly well. I still have that vibration during 1100-1200 RPM range and very light at the RPM's just above my crusing range 1900-2200. Other than that it seems to be good. During the next haulout the shaft is coming out to be checked. Don't know if I mentioned this but the cutlass bearing, mounts are less than 18 months old. Once we confirm that the shaft is true we will go at it from back to front and make all right in my boating world for a short time until the next thing breaks.
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