Prop play

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Bluevee

Bluevee

Veteran Member
Joined
Mar 21, 2014
Messages
25
Location
Australia
Vessel Name
Lady J
Vessel Make
Clipper 30
Hello all,
Just completed slipping the boat. Mostly went ok, just a bit concerned about a bit of prop shaft play. I would say about 3 mm (1/8) play. It doesn't vibrate or leak- just wondering if it's normal?
 
Last edited:
Cutlass bearings wear over time. If you're not getting noticeable vibration, I wouldn't worry about it. If you need to pull the shaft at some point in the future, that's a good time to replace the bearing. The bearings themselves aren't that expensive. If you can't do it yourself, the labor will be a significantly higher cost. Just did mine on my 13' long 2.5" shaft. In the process of a repower and wanted to redo the dripless seal and cutlass bearing, and have the shaft checked. Think the bearing was 2 or 3 hundred dollars and maybe a couple of bucks for the ibuprofen for the one day of grunt work.

Ted
 
Chung hwa clipper

Thanks Ted, don't fix what isn't broke -yet. I don't think I've got a cutlass bearing, I'm trying to post a photo of it. Hopefully I can. The CHB owners might be familiar with these
 

Attachments

  • image.jpg
    image.jpg
    108.6 KB · Views: 171
Last edited:
Bluevee:

The cutlass bearing is in the stern tube just in front of the prop.

1/8" play is a bit much, but if it doesn't vibrate, then leave it alone.

David
 
djmarchand is right, too much play.
Further; on a boat, if you wish troublefree operation and no towing, you do fix things b/4 they are broke.
 
Bluevee said:
Hello all,
Just completed slipping the boat. Mostly went ok, just a bit concerned about a bit of prop shaft play. I would say about 3 mm (1/8) play. It doesn't vibrate or leak- just wondering if it's normal?
Click to expand...

What is the shaft size? The smaller the shaft the less play allowable.
 
Thanks all

I haven't measured the shaft dia - but guessing about 1 1/8 " I was curious about the two bolts on the sides of the housing- shaft tube (I presume this houses the cutlass bearing)
 

Attachments

  • image.jpg
    image.jpg
    132.1 KB · Views: 194
Bluevee said:
I haven't measured the shaft dia - but guessing about 1 1/8 " I was curious about the two bolts on the sides of the housing- shaft tube (I presume this houses the cutlass bearing)
Click to expand...

The cutlass bearing is generally a press fit into the stern tube. The 2 bolts on the side lock the bearing in place (generally they are set set screws. It most cases, you remove the shaft and then unbolt the stern tube from the boat. The old bearing is removed (mine required cutting the bearing with a long sawsall blade and then internally pealing it). Then a new bearing is pressed in with a hydraulic press. Then you reassemble and do an engine alignment to make sure everything is properly allighned so you don't get excessive cutlass bearing wear.

Ted
 
I just replaced both or ours. One at each end of the shaft tube. The one on the aft end of the tube was easy, the one on the forward end was a pain in the butt. You should not need to use a press to install the new one. It should slide in with some gentle persuasion. I was given some advice by an old mechanic that I highly respect to not remove the tail piece from the keel. He stated that it usually opens a bigger can of worms than you want to deal with. Just replace the bearing and check the engine alignment. We have an 1 1/2" shaft and the bearings cost $70 each.
 
1/8" on a 1 1/8" shaft seems excessive to me. I'd want it to be a quarter of that. Do you have a dial indicator?

Not the end if the world if vibration "seems" OK, but I would plan on changing it in the near future.

Not a big deal to change.
 
1/8" is excessive play.

The important thing is ..... The more worn it is, the faster it wears.

At some point you will score the shaft and that will cost a lot more than $70 for a bearing.

If you are doing a few weekend trips per season, you will get away with it for a couple of seasons. If you are cruising south on the ICW in abrasive sandy water it will wear much faster.

From your photograph it looks like the rubber bearing is grossly distorted which indicates that it is breaking down very quickly.

The arrow points to the bearing in the shaft log. DO NOT pull the shaft log to get the bearing out, that will just give you the headache of re-aligning everything.
 

Attachments

  • bearing.jpg
    bearing.jpg
    26.4 KB · Views: 504
Last edited:
Wished I'd known

I wished I'd known the bearing was that worn, the little difficulties of boat ownership become apparent - not like I can just jack it up and get stuck in. Thank you all for your knowledge & input - you blokes are a goldmine. Hopefully it gets through to next haul out - or that sleeve bearing looks interesting. Would the boat still have to be taken out I wonder?
 
READY2GO said:
I just replaced both or ours. One at each end of the shaft tube. The one on the aft end of the tube was easy, the one on the forward end was a pain in the butt. You should not need to use a press to install the new one. It should slide in with some gentle persuasion. I was given some advice by an old mechanic that I highly respect to not remove the tail piece from the keel. He stated that it usually opens a bigger can of worms than you want to deal with. Just replace the bearing and check the engine alignment. We have an 1 1/2" shaft and the bearings cost $70 each.
Click to expand...

Wonder what your old mechanic is talking about with the can of worms. Shaft tubes are removed and replaced fairly easily by most competent mechanics. The stuffing box and coupling hose need to be removed. The tubes as pictured in this thread, are held in place with 2 or 4 bolts which are removed, and then you just break the caulk loose. I get my work done in a commercial yard that caters to Chesapeake Bay waterman. The yard pulls 1 or 2 stern tubes every month. Most are on fiberglass boats, but a fair number are on wood boats. These boats can run in access of 2,000 hours a year in the shallow waters of the Chesapeake . Replacing cutlass bearings is a common occurrence. In many cases the shaft isn't removed, they just pull the prop and then the stuffing box is removed. They do an inspection of the shaft tube and hardware, replace the cutlass bearing, inspect and service the stuffing box and connecting hose as necessary, and reassemble. Haulout, service, and back overboard usually the same day. Pulling a stern tube is really no big deal if you know what your doing and it's a serious commercial yard.

Ted
 
O C Diver said:
Wonder what your old mechanic is talking about with the can of worms. Shaft tubes are removed and replaced fairly easily by most competent mechanics. The stuffing box and coupling hose need to be removed. The tubes as pictured in this thread, are held in place with 2 or 4 bolts which are removed, and then you just break the caulk loose. I get my work done in a commercial yard that caters to Chesapeake Bay waterman. The yard pulls 1 or 2 stern tubes every month. Most are on fiberglass boats, but a fair number are on wood boats. These boats can run in access of 2,000 hours a year in the shallow waters of the Chesapeake . Replacing cutlass bearings is a common occurrence. In many cases the shaft isn't removed, they just pull the prop and then the stuffing box is removed. They do an inspection of the shaft tube and hardware, replace the cutlass bearing, inspect and service the stuffing box and connecting hose as necessary, and reassemble. Haulout, service, and back overboard usually the same day. Pulling a stern tube is really no big deal if you know what your doing and it's a serious commercial yard.

Ted
Click to expand...

You seem to be confusing the shaft tube with the shaft log. The shaft tube is usually (not always) not a big job to remove unless it's metal and corroded.
There is absolutely no need to remove the shaft log to replace the shaft, stuffing box or cutless bearing...... and I'd sure like to know how you remove a cutless bearing from a shaft log without pulling the shaft !
I've done more than a few cutless bearing changes and I would love to know how to make it easier.
 
The million dollar question I would guess the mech is worried about is how easy will it will be to remove the bearing carrier aft and the bolted on part of the stuffing box forward.

If the are corroded on the shaft tube or the shaft tube breaks while trying to remove either, ooops.

Not all boats are set up this way but many are. If it were me and I did not know more about the boat, I would be worried what I was getting into also.

Not sure how easy if even possible to remove the cutless from an aft bearing carrier like this one, though from a stand alone strut I have seen bearings changed without pulling the shaft.
 
Last edited:
DSCN7158.jpg

DSCN7200.jpgOur shaft tube is a fiberglass tube and is built into the keel. It has a fiberglass flange on the forward end which is at a bulkhead. It can not be removed. The aft bearing carrier has four bolts that attach it to the keel. You can not access these bolts from the inside, so you do not know if the builders used studs with wood screw type threads and installed them after the keel was laid up or if they just laid regular bolts in as they built the keel. If they did the latter and one spins while you are removing the nuts holding the carrier on you are in for a big job.

The cuttless was easy to remove from the carrier and don't see any reason I would need to remove the carrier anyway.

All boats are different and most advise doesn't fit all boats.
It may not be a problem on other boats.
 
Last edited:
love that blue prop

I think on consideration I wouldn't remove the the shaft log, just remove the bearing insitu. I think a press could be fabricated by using the shaft log mounting bolts to hold it square to the tube and press the bearing in off that. It may just tap in as well off a soft hammer. The question is now how to I obtain the OD and length of the bearing needed to be ready to swap in out, I have no documentation - specs.
 
Bluevee said:
I think on consideration I wouldn't remove the the shaft log, just remove the bearing insitu. I think a press could be fabricated by using the shaft log mounting bolts to hold it square to the tube and press the bearing in off that. It may just tap in as well off a soft hammer. The question is now how to I obtain the OD and length of the bearing needed to be ready to swap in out, I have no documentation - specs.
Click to expand...

The bearing length is four times the diameter of the shaft If your shaft is 1 1/2" the bearing will be 6" long. You can measure the shaft inside the boat behind the transmission. You will have to also measure the diameter of the bearing itself which will have to be taken off the bearing itself. Could be done in the water. You should not need a press to install the bearing. If you can not tap it in then something is wrong. The reason they have two set screws to hold them in place is because they are not press fit.

I would not plan on doing this in two hours while it is in the slings. Sometimes they can be a pain to remove, and other issues may arise. Plan on a weekend and hopefully it will only be a few hour job.
 
Corrosion/debris accumulation (whatever you call it) can lock them in pretty tight, I have often had to cut them out or press them out so be prepared to do so.
 
Qualified on the subject

Psneeld, I've read some of your other posts on this subject - sounds like you've felt the pain. Would you ever remove the shaft log unless completely necessary? It looks as though a lot of these single chb 's have the same shaft log- surely they would have the same cutlass bearing
 
I wouldn't unless I had a really bad leak from it.

Suggestions to insert a fiberglass insert sound promising if there is room.
 
You must log in or register to reply here.

Similar threads

E
Spare prop?!
Replies
27
Views
2K
ronobrien
R
DW1979OA
Over propped. Is it really a problem?
3 4 5
Replies
123
Views
7K
Jeff F
Jeff F
J
Singing prop? Cutless bearing?
Replies
8
Views
991
lwarden
lwarden
S
Prop recommendation
Replies
5
Views
656
DNT99611
D
RickyD
How many things can go wrong in one day???
Replies
14
Views
2K
Dougcole
Dougcole

Latest posts

Back
Top Bottom