shaft and strut questions
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=9117
Printed Date: September-30-2024 at 1:09am
Topic: shaft and strut questions
Posted By: Datim
Subject: shaft and strut questions
Date Posted: December-03-2007 at 3:36pm
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I was out on the lake the other day (I'm spending the winter down in Mexico) and I hit a fishing trap that was built with rebar. I was only going about 10mph and stopped immediately after having hit it and was able to get towed into shore.
Once I got home I cut away the rebar. a 18" section was completely wrapped around the prop and shaft. The only damage that I could see was a small fingernail sized nick in the prop and no other visible damage to the boat or the shaft, etc. That was a great relief. However, when I was checking things out I noticed that there is a little side to side play in the shaft at the strut. You have to wiggle it with a moderate amount of force to get the play, but it's there none-the-less. My question is, is this normal or should there not be any amount of play at all? If there is play, what do I need to do? Also, could my shaft have possibly gotten bent after having hit something like that? how can I check to see if my shaft is straight? Oh, I forgot to say: I have a 1983 SN2001. I bought it about 6 months ago for cheap, but it's needed a fair bit of work. Mostly small things, but not much is new on it. Thanks for the help, I really appreciate it. |
Replies:
Posted By: JoeinNY
Date Posted: December-03-2007 at 4:14pm
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There should be no play. If the strut itself is moving at all you need to remove and rebed. If its the strut staying still and the shaft moving then you need http://www.skidim.com/prodinfo.asp?number=SB10X12 - new strut bearings . Its a wear item probably nothing to do with your rebar hit. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1477 - 1983 Ski Nautique 2001 1967 Mustang 302 "Decoy" http://www.youtube.com/watch?v=cO5MkcBXBBs - Holeshot Video |
Posted By: BuffaloBFN
Date Posted: December-03-2007 at 5:01pm
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It's been my experience that inboard drive components don't react very well to sudden changes in direction. I hope Joe's post is all the help you need, but I would investigate further. I recently had a prop with a slightly bent blade that could only be seen on the workbench....at least by me. The strut and shaft may also be slightly out.
There are several posts here on prop/shaft damage and on alignment. There's a couple of ways to check things, but I'm not really the guy to describe it. This is a long thread but super good info within! http://correctcraftfan.com/forum/forum_posts.asp?TID=6037&KW=alignment - Eric's alignment thread ------------- http://correctcraftfan.com/diaries/details.asp?ID=2331&sort=&pagenum=12&yrstart=1986&yrend=1990" rel="nofollow - 1988 BFN-sold "It's a Livin' Thing...What a Terrible Thing to Lose" ELO |
Posted By: Datim
Date Posted: December-03-2007 at 5:20pm
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Thanks for the help so far. The play in the prop strut is the shaft itself moving, the strut itself is solid and doesn't move. So it looks like I'm going to have to get new strut bearings.
Thanks for the link to that thread. I had looked around, but for some reason didn't see that one. |
Posted By: BuffaloBFN
Date Posted: December-03-2007 at 5:36pm
As noted, this wouldn't be from an impact. The thread I mentioned has some info in it on a possibly bent shaft. I think I've also read that bent shafts/props can be hard on the tranny. Try sighting down the keel...is everything that's supposed to be straight down still that way? Is the end of the prop shaft on one side of the rudder of the other? If you can turn the prop by hand, does the shaft end maintain center? This is not the preferred way to check, but it might help you notice something. ------------- http://correctcraftfan.com/diaries/details.asp?ID=2331&sort=&pagenum=12&yrstart=1986&yrend=1990" rel="nofollow - 1988 BFN-sold "It's a Livin' Thing...What a Terrible Thing to Lose" ELO |
JoeinNY wrote:Posted By: Datim
Date Posted: December-03-2007 at 6:12pm
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Everything looks straight and in line by eyesight, but I'll do a more thorough check just to be sure.
BTW, if there is play in the prop strut, would that cause vibration at all? |
Posted By: BuffaloBFN
Date Posted: December-03-2007 at 6:27pm
Yes, it will as Joe said. Did it have the same vibration before the rebar? Has it gotten worse? Some vibration should be expected if your cutlass bearing is worn, but if it's gotten worse you probably have something bent. Some here say that if you hit something harder than a dead fish, you'll surely have bent something.  ------------- http://correctcraftfan.com/diaries/details.asp?ID=2331&sort=&pagenum=12&yrstart=1986&yrend=1990" rel="nofollow - 1988 BFN-sold "It's a Livin' Thing...What a Terrible Thing to Lose" ELO |
Posted By: 87BFN owner
Date Posted: December-03-2007 at 7:03pm
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Not always is something bent after hitting something, but the alignment has changed. The alignment needs to be checked at the coupling with feeler gauges as shown in Eric's thread. Some bends can be seen with they naked eye if they are bad enough, others will only be seen by measuring. ------------- |
Posted By: 8122pbrainard
Date Posted: December-03-2007 at 7:34pm
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Datim, A bent shaft forward of the cutlass can be checked at the coupling halves and is explained in Eric's alignment thread. If it is bent aft of the cutlass around the prop taper, then a dial indicator clamped to the strut while the shaft is rotated will tell. The dial indicator can be used forward as well. If you could borrow one, I would use it. The only other way is to remove the shaft from the boat and put it between V blocks. I wouldn't trust the naked eye. You do not want to end up with trans problems. ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: 8122pbrainard
Date Posted: December-03-2007 at 8:47pm
Or this?
Don't worry, this is a extreme case of someone who didn't know what he was doing!!! ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: JoeinNY
Date Posted: December-03-2007 at 8:51pm
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Pete its not nice to talk about reid like that during the holiday season. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1477 - 1983 Ski Nautique 2001 1967 Mustang 302 "Decoy" http://www.youtube.com/watch?v=cO5MkcBXBBs - Holeshot Video |
Posted By: Datim
Date Posted: December-03-2007 at 9:07pm
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Thanks a lot for the info, it's very helpful. I did take the boat out yesterday for a short trip and everything seemed normal. I only use it at wakeboarding speeds (under 22mph) and at those speeds I didn't really notice any vibration or anything different. However, when bringing the boat back in I took it up to between 25 to 30 mph and there was noticeable vibration. I could feel it in the throttle. I can't recall if it made that vibration before as I don't ever remember taking it over 25mph. I'm assuming that the vibration at higher speeds is probably due to the strut bearing needing to be replaced, though now that I've got all this info, I'm going to check the alignment and the shaft to make sure that is all in order. I certainly don't want to mess up the transmission.
How can I tell whether my prop needs to be repaired? From looking at it it looks like it only has one little nick in it and nothing else. Is it most likely that I'd need to get it rebuilt? If I don't am I risking harm to my boat or is it just a matter of losing some performance? |
Posted By: 8122pbrainard
Date Posted: December-03-2007 at 10:05pm
Joe, That's Reids boat???? Datim, Just like the shaft, it is really hard to tell by eye if the prop is bad. If you have the time, sending it to a prop shop may not be a bad idea. ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: TRBenj
Date Posted: December-03-2007 at 10:20pm
Yup. From http://correctcraftfan.com/forum/forum_posts.asp?TID=6449&TPN=3 - this thread. You cant even remember where youre stealing your pictures from Pete? 
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Posted By: 8122pbrainard
Date Posted: December-03-2007 at 10:55pm
Tim, I remember the thread very well. That's how I knew where to steal the picture! ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: eric lavine
Date Posted: December-04-2007 at 10:33am
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A last ditch effort if no tools are available (such as indicators) would be to c-clamp a screwdriver tip near the possible bend, you can pick up a bent shaft this way with the eye, if set up right you could even use feeler blades to measure it even though there is no need to measure the bend, because its bent anyways, put the tip of the scredrver as close as you can to the shaft and clamp it if there is even a slight bend you will see it with this method. edit...make sure you turn the shaft ------------- "the things you own will start to own you" |
Posted By: 8122pbrainard
Date Posted: December-04-2007 at 11:54am
Just in case anyone hasn't seen or used a dial indicator, here's a picture. The contact point is placed on whatever you want to measure. As the surface moves this point up or down (as in the case of a bent shaft) the dial indicates the movement. Typically in .001" increments
 ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: Datim
Date Posted: December-04-2007 at 4:20pm
| Thanks everyone for the helpful information. I'll be checking everything out this weekend and will report back. Hopefully all I'll need to do is replace the strut bearings and send the prop to get checked out. I really appreciate all the good info. |