Cutless bearing. - To change or not to change

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Lozzer

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The boat I skipper is now 2.5 years old. We have navigated some 12,000 nm and I'm wondering if it is time to change the cutless bearings.

I have just received the quote from the boatyard and they are saying €8500 plus cost of extra days hard standing. They have indicated 130+ man hours for the job! So an extra 8 days on the hard....

We will no doubt be covering another 6000nm this summer and not sure I want bearings with that many miles on them. What would be the general consensus, change or not?
 
Lozzer said:
The boat I skipper is now 2.5 years old. We have navigated some 12,000 nm and I'm wondering if it is time to change the cutless bearings.

I have just received the quote from the boatyard and they are saying €8500 plus cost of extra days hard standing. They have indicated 130+ man hours for the job! So an extra 8 days on the hard....

We will no doubt be covering another 6000nm this summer and not sure I want bearings with that many miles on them. What would be the general consensus, change or not?
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is the boats name the "Spirit of Dover" by any chance?
 
that sounds like a lot of money, how big is the boat, how many cutlass bearings are there? can you just change the ones in the P bracket using a sleeve puller? or do you want to do the ones behind the shaft seals as well - that generally don't wear much.
 
Hi

Boat is a Princess 85.

My though process was to change only p-brackets as gap between shaft coupling snd stern tube is not great.

Interestingly just received a competitive quote at less than half the price!

Not sure about rip off Britain. Spain does a nice job as we'll.
 
I'm no expert, but about 500 hrs (at 25 kts) seems early to change the bearings when you're in nice clear med waters. Might be a different story if you were running in silty water. Is there any vibration underway, and has the boat been out the water to check how much play there is in them?
 
if they are sufficiently worn to warrant changing you can tell more when running in reverse. don't know why, but if you motor forwards @ 6kns then motor backwards see if the boat feels different. If they are worn you can feel it through your feet - a rumbling sensation.
just noticed the quoted time of 130 hours - it usually takes 2 -3 days if you take the shafts out, an afternoon if you can pull them out.
 
Lozzer said:
Hi

Boat is a Princess 85.

My though process was to change only p-brackets as gap between shaft coupling snd stern tube is not great.

Interestingly just received a competitive quote at less than half the price!

Not sure about rip off Britain. Spain does a nice job as we'll.
Click to expand...

MAYBE THE SIZE OF THE BOAT MAKES FOR A HUGE QUOTE?? How much for a 23foot duver. LOL
 
When the boat is out of the water see how much movement there is when you lift the shafts, should be less than a mm.

If more movement than that or delaminated or slipped rubber, replace, not normally undertaken on hours or miles.

Order a spare set to keep on board.

Probably a full bearing in the p bracket and a half one in the sterntube so two full and two half.

Sounds a bit steep but med rates are.
 
We cruise predominantly at displacement speed, 10.5-11.5 knots... HUGE saving on cost of fuel. So boat has circa 1100 hours on the clock. If we were talking 500 I would agree that they probably don't need changing.

Size of boat should only reflect in cost of parts, surely labour time is the same know matter how big or small (within reason).

As you will see I'm not an engineer but struggle to see 130 hrs to draw two shafts.

Thank you for the note about going astern now that you mention that I wondering if there could be something in it. I'll give it a try next week.
 
Too many variables, silty water, high shaft speeds will increase wear. Mine has done 17 years, about 14000 hours, 30,000-40,000 miles, max revs on the shaft 700 rpm. No discernible wear yet.
 
Lozzer said:
Hi

Boat is a Princess 85.

My though process was to change only p-brackets as gap between shaft coupling snd stern tube is not great.

Interestingly just received a competitive quote at less than half the price!

Not sure about rip off Britain. Spain does a nice job as we'll.
Click to expand...

Actually you might be a little unfair on the first quote.
From what I've heard and seen, cutlass bearings can be easy to get out or they can be real pigs.
Maybe the first quote was just covering himself.

Maybe a fairer approach would be to agree on a "time and materials" basis.
 
Hurricane said:
Actually you might be a little unfair on the first quote.
From what I've heard and seen, cutlass bearings can be easy to get out or they can be real pigs.
Maybe the first quote was just covering himself.

Maybe a fairer approach would be to agree on a "time and materials" basis.
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Time and materials is a blank cheque. If t he yard is not busy, why would it not just book as many hours as it thinks it can get away with?
 
rafiki_ said:
Time and materials is a blank cheque. If t he yard is not busy, why would it not just book as many hours as it thinks it can get away with?
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That's often best for the customer as long as you trust the yard carrying out the work, I have to do this all the time, you only rip someone off once and word gets around then you don't get any more work.
When giving a price you have to look at worst case as yards don't do work to loose money.

However the hours quoted seem to be way OTT, I would check the yard have the correct pullers for this size or it will take a lot longer.
 
Lozzer said:
We cruise predominantly at displacement speed, 10.5-11.5 knots... HUGE saving on cost of fuel. So boat has circa 1100 hours on the clock. If we were talking 500 I would agree that they probably don't need changing.

Size of boat should only reflect in cost of parts, surely labour time is the same know matter how big or small (within reason).

As you will see I'm not an engineer but struggle to see 130 hrs to draw two shafts.

Thank you for the note about going astern now that you mention that I wondering if there could be something in it. I'll give it a try next week.
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Lozzer, wear is a function of revolutions not hours. So if you have 1100 hours at 11kts that's broadly same as 550 hours at 22kts. In the clean water of the med they should not be worn at that level of use. You should get something like 1000hours at 20kts, or even more. You can check when you haul out

Changing them should be a day's work. You pull the props off and then loosen the retainer screws and whack them out aft wards (or more likely use a puller and packer tube). Two men for one day should do it for a yard with the right gear
 
Hours seem high but ?

Does Quote include lift out, relaunch and pressure wash ?

Sometimes with four or five bladed props you cant get a puller on to the prop to pull it off due to over lapping of the props.

Removal of the upper cutless bearings in the stern tube requires pulling the shafts out did you request this or has it been included ? These don't normally need to be changed as often as P bracket cutless bearings.

Most cutless bearings you can remove the cutless by pulling a "shell" two half pipes that fit around the shaft but inside the P bracket that pick up the end of the cutless and pull it out with the shaft in place, obviously requires removal of the props.

Lift out, Relaunch Pressure wash, remove props, draw shafts out replace four cutless bearings, refit shafts, props and relaunch probably not that far out?

Unless already done , a custom puller can be made up, the props can be both drilled ( when removed from the boat) and tapped for two bolts spaced wider than the width of the prop nut with a heavy duty plate across the two bolts over the end of the shaft , the plate is drilled and tapped in the centre for a large bolt . Loosen off the prop nut by say 20 mm, fit puller bolts to both props, keep plate parallel to prop boss rear face, fit centre bolt and wind up pressure, apply heat to prop boss with propane flame and the prop normally jumps off to be stopped by the prop nut, if this is done prop removal for two props say only 1 to 2 hours. Keep the custom puller on board to reduce future prop removal problems and time involved. I have a custom puller for my props every boat should have one.
 
jfm said:
Changing them should be a day's work. You pull the props off and then loosen the retainer screws and whack them out aft wards (or more likely use a puller and packer tube). Two men for one day should do it for a yard with the right gear
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If you were going to the effort of replacing the P bracket cutlass bearings, it would probably be best to replace the ones in the hull as well so the shafts would need to come out as well which involves pulling the gearbox flange off as well. It would be best to remove the shafts anyway in case you get a P bracket cutlass bearing stuck - it may require cutting out. This in turn needs the rudders to be removed and, of course that means that the boat needs to be "blocked off" high enough to get the rudders out. And, of course, all the rudder assembly and seals will need careful attention. With shafts out, the seals would probably need replacing - I say probably because Princess do have a spare seal or two on the shaft but it would make sense to put the spare ones back where they are.

I think you make it sound an easy job.
I'm sure it isn't.
Do-able of course but all needs careful consideration.
Personally, I expect that the more expensive quote is the price you would end up paying - one way or the other.
 
You generally dont change the sterntube cutless as aoften as the P bracket cutless bearings.

If you have the equipment ie shells as i refer to them above you can normally get the cutless bearings out of the p bracket with the shaft left in situ.

Removing cutless bearings where you cant use shells is often a pig of a job its a shaft out job and we use the equivalent of a corks screw to pull them out.

The prop would need to come off and most shafts on modern vessels are offset so you can remove the props (and shaft if required) with the rudders left in place, but not all.

Stern seal replacement is normally 5 years sometimes 7years depending on the manaufacturer.
 
Hurricane said:
I think you make it sound an easy job.
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Sure, but there is no proper info from OP (as is often the case here with tech questions, as you well know!). I assumed he meant just the P bracket bearings, which feels right for such a new boat though I'm guessing. You assumed he meant the engine-end bearings as well, which feels wrong for such a new boat but I appreciate you are guessing too and neither of us knows the correct answer and OP isn't telling us! If your guess is correct, ie all 4 bearings, then it is a big job exactly as you say. If my guess is correct, it is an easy job on a newish boat
 
Sorry to sound stupid but could someone explain what a cutlass bearing is? i assume its the bearing that the shaft sits in as it goes through the hull and into the gearbox?

I clearly am not technical but often peoples explinations here are better than i can find on google as they are less technical!
 
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