I agree it sounds like alignment. Judging from the yards comment they also take propellors off with a hammer. I bet they slid the new strut on the shaft and torqued the bolts without the coupling even being loosened. That would have bound your shaft. Even if the new strut is identical and same bolt holes used, tolerance in bolt holes, bedding compound and the bolt torquing sequence will change alignment. Once a new strut is secured in place the engine needs to be aligned to the strut. If it is beyond the adjustment limits of the engine mounts, the shims can be used under the mounts.
New Strut and now shaft wont turn
- Thread starter Muffy
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I had a similar problem on my 1980 H30. A mechanic changed my motor mounts and then aligned the engine to the shaft - so he said. I could barely turn the shaft by hand when the engine was in neutral. The mechanic even went so far as to claim that my boat had somehow suffered structural failure and sagged at the stern - thus causing the shaft to bind. He suggested that I get rid of the boat as soon as possible. I hired a marine surveyor to assess the problem. Turns out that the mechanic had moved the shaft before alignment and the shaft was now binding in the strut. I had the yard and a new mechanic align the strut to release the binding and all was well.
$0.02 from the designer of many marine powertrains:
Some important points haven't come out here yet. Which shipyard guy said that? If it is just a worker bee, blow it off. If it's the guy who will be making the decisions about what to do next, you have a big problem because he knows &^%#@(*& that he's spouting crap and they are trying to avoid redoing a job they know they screwed up. If they can BS you for a couple more weeks Alaska sailing season will be over and they can work on it all winter. Hold off even mentioning lawyers until the last possible moment but I'll bet you are going to be talking to one before this is over.
Cheerfully ask them to verify. Disconnect the shaft and run the engine. It should easily and normally run up to mid RPM in forward and reverse. You should be able to easily turn the coupling by hand in neutral. The prop can only go on one way so, unless you put on a different one....
Is there a bearing just behind the stuffing box or any other bearing in the shaftline aside from the one in the strut? Usually there isn't on boats like this and the stuffing box has a hose. (BTW, if there is a hose, replace it now regardless of how good it looks.) Single bearing shaft lines are very tolerant. Alignment will be more critical on a two bearing system.
If it is a two bearing system, you should be able to now just try turning the shaft. It should be easy to turn by hand. If the boat is out of the water, you have to be sure the Cutlass bearings are wet with a hose which may be difficult with some shaftlines. If it doesn't, the strut needs to be ripped out and reinstalled. I'm assuming that strut was glassed into place. If it is bolted on, it can be shimmed or the glass under it ground down to get the proper alignment. The shipyard needs to consider the scale factor if they are working to the tolerances they are used to on large fishing boats. Do they ever work with small shaft lines like this?
If there is a single bearing in the strut and a flexible stuffing box, you should wedge and block the shaft coupling exactly in place before disconnecting the engine. With either kind of shaftline, any visible shifting of the engine or angular misalignment of the coupling halves after the bolts are removed immediately indicates the source of the problem.
With the single bearing / flexible stuffing box arrangement, remove the hose (which you should replace anyway at every opportunity) and block the shaft exactly in the center of the forward end of the shaft log. Now put a feeler gauge at the top, bottom, and each side of the stern bearing forward and aft. There should be no clearance at both ends of the bottom and side and top clearances should be the same at each end. Lubricate the blocking so you can verify that the shaft turns easily.
If all this checks out, you may have bent the shaft when the old strut failed.
There is a lot more to this. I could go on for pages but I'm out of time. Besides, the shipyard has to be honest and competent regardless of how much advice you get on an Internet forum. I'd be glad to keep giving you what help I can but I'm leaving shortly for a 20 day cruise away from Internet contact (one of the big reasons to go cruising now
If you go to a local Cat dealership, they will probably give or let you copy one of their standard manual sections on shaft alignment. It's directed towards big shafts but the prinicples apply. Othere engine companies have similar publications but Cat's were the best the last I looked. I wish I could go to the office before I leave and could send you a pdf.
Good luck.
Sad but true
I'll be very interested in the outcome of this, both as far as what was the problem and how the yard dealt with it.
PS. I made that assumption on your sex based on the name. If I'm mistaken, please, no offense intended.
I take it, Muffy, that you are a woman? If that is true, I think we all know that mechanics tend to treat women differently than men. They assume (1)the woman knows nothing; and (2)she can be easily intimidated by the man's (supposedly) superior knowledge. I think it's important to be extremely firm and confident about your rights with them. Also, my experience is that it often doesn't hurt to bring a few friends or, in this case fellow sailors along, if it looks like the business will try to evade their responsibilities.
I'll be very interested in the outcome of this, both as far as what was the problem and how the yard dealt with it.
PS. I made that assumption on your sex based on the name. If I'm mistaken, please, no offense intended.
nope. Muffy is what this boat was named in 1995, its no longer Muffy, but i always liked the naked lady that was on the side of the boat when it was called muffy.
i am very much a man.
I had the machine shop guy come over and check the shaft, and he said it is fine.
I live in a town with no roads that lead here, and the same guy owns both the shipyards here. total population is around 30k. not a ton of options when it comes to boat doctors.
i am starting it with a bucket for raw water today and checking the tranny and shaft, then taking the prop off because they say if it doesnt feather in the water, it will kill the engine. i will let you know the progress as it happens.
thanks again
i am very much a man.
I had the machine shop guy come over and check the shaft, and he said it is fine.
I live in a town with no roads that lead here, and the same guy owns both the shipyards here. total population is around 30k. not a ton of options when it comes to boat doctors.
i am starting it with a bucket for raw water today and checking the tranny and shaft, then taking the prop off because they say if it doesnt feather in the water, it will kill the engine. i will let you know the progress as it happens.
thanks again
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I don't understand why you are being told to remove the prop. The prop shouldn't have anything to do with your problem. A prop that doesn't feather is just the same as a fixed blade prop and will not kill the engine. Whoever told you that just doesn't have a clue as to what they are talking about. Have you disconnected the shaft from the transmission yet? That should be the first thing you do. It sounds like you are getting some poor advice from so called "professionals". The advice given to you at this forum has been spot on.
removed the prop because they said its a left hand rotation with a right hand prop, and i have been running in reverse to go fwd.
so the 2 blade max prop can be set up left handed, and i did just that, got dropped in the water and im now at 3 1/2 knots and a staggering 700 rpm full throttle. reverse almost kills the engine and will do 400 rpm. this is a westerbeke 2b 18 horse with 30.4 hours on the motor and gear box. when i pulled this boat in to paint the bottom, i had no idea i had any problems, ran almost 7 knots aparently, in reverse, and it ran fine in rev/fwd too.
after this new strut was installed,i was told i have my prop on backwards , which when i removed i found the nut was on less than hand tight.
i am disgusted. when i came around to the dock, i saw the yard manager driving out.
i went back to my slip and tied up for the night.
i am considering getting a diferent prop to put on and if it acts the same i will just tell them its now definately the strut.
i am doing my best to be cool about this.
lets not forget, when i went in for bottom paint, i cruised over at 14-1500 rpm, 7 knots, and BACKED in the hall out slip, first try in the wind. this boat was handling great.
so the 2 blade max prop can be set up left handed, and i did just that, got dropped in the water and im now at 3 1/2 knots and a staggering 700 rpm full throttle. reverse almost kills the engine and will do 400 rpm. this is a westerbeke 2b 18 horse with 30.4 hours on the motor and gear box. when i pulled this boat in to paint the bottom, i had no idea i had any problems, ran almost 7 knots aparently, in reverse, and it ran fine in rev/fwd too.
after this new strut was installed,i was told i have my prop on backwards , which when i removed i found the nut was on less than hand tight.
i am disgusted. when i came around to the dock, i saw the yard manager driving out.
i went back to my slip and tied up for the night.
i am considering getting a diferent prop to put on and if it acts the same i will just tell them its now definately the strut.
i am doing my best to be cool about this.
lets not forget, when i went in for bottom paint, i cruised over at 14-1500 rpm, 7 knots, and BACKED in the hall out slip, first try in the wind. this boat was handling great.
I am going to go out on a limb here and say that it sounds like the new feathering prop “pitch stops” are not set correctly.. I mean they are letting the blades stay flat .. like if they were to stay feathered ..when the transmission is in gear.. which turns the prop into a paddle wheel and would make high drag and almost no propulsion.. YES the shaft and strut still need alignment but the engine has enough power to fry the Cutless if it were making a lot of drag.. YES the yard is spouting some really smelly goo!.. But it really sounds like the prop is at fault and is not pitching correctly as the shaft starts to turn.. You should be able to troubleshoot this on the hard without the engine running. Break out the instructions (noooooo) and get with it! Good Luck!
i got the video off the max prop site and took the laptop down to the yard, and we put the prop together set by step with the video. the only thing different in the video was the keeper pin for the shaft nut goes thru the nut on mine and they go beside the nut on the video.
this is where i found the loose nut on the shaft. when the yard guy put it back on something was different and he couldn't get the pin in with the nut tight so he backed it off to get the pin in, and that kept the cone gear from fully seating. after we corrected that, it seemed to work smoothly.
its not a new prop, its the one that has been on the boat since 2001.
this is where i found the loose nut on the shaft. when the yard guy put it back on something was different and he couldn't get the pin in with the nut tight so he backed it off to get the pin in, and that kept the cone gear from fully seating. after we corrected that, it seemed to work smoothly.
its not a new prop, its the one that has been on the boat since 2001.
You can spend the rest of your boating life messing with the prop but that is not your problem and has not been. By the description you gave the strut is not installed correctly and the alignment is not correct. Until that is taken care of you are no closer to solving your problem then you were before. So the big question is, why are those things not being corrected? Chuck
If this is with a wide open throttle you should be blowing a ton of black smoke! You have run with a wide open throttle haven't you since you had the strut replaced?
Muffy- you have to start looking at this in a more systematic manner in an effort to isolate the problem. I don't think you are going to hurt the motor touching 3600. If that is ok, then concentrate on your strut/shaft/prop. It sure does not sound like the strut alone is causing the problem. But if the engine revs to WOT and the coupling turns by hand in neutral, then I would do a good alignment (if you can- strut may be too far off)
then try it again . I would not think it sounds like the strut is so far off that it could bind the shaft enough to stall the motor. This is awkward because some things need to be done in the water and some better out. I would still suspect some damage to the transmission
then try it again . I would not think it sounds like the strut is so far off that it could bind the shaft enough to stall the motor. This is awkward because some things need to be done in the water and some better out. I would still suspect some damage to the transmission
the tranny and motor came in the crate together
both have 30.4 hours on them
i blew black smoke with a wide open throttle whenit would only turn 400 rpms
now at 24 degrees on the prop, i run 1700 and no smoke but a full 2 knots slower than
i ran at 1500 rpms before the new strut and i could run up to 2000 rpms but little increase in speed
there was no need to run at a higher rpm when i got 6.8 at 15-1600, that was about as fast as i need to go in any situation.
i have no idea what the prop was set at before the haul out. all i do know is that it was set at a right hand setting. now its set at a left.
both have 30.4 hours on them
i blew black smoke with a wide open throttle whenit would only turn 400 rpms
now at 24 degrees on the prop, i run 1700 and no smoke but a full 2 knots slower than
i ran at 1500 rpms before the new strut and i could run up to 2000 rpms but little increase in speed
there was no need to run at a higher rpm when i got 6.8 at 15-1600, that was about as fast as i need to go in any situation.
i have no idea what the prop was set at before the haul out. all i do know is that it was set at a right hand setting. now its set at a left.
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