superheat6k
Well-known member
I think you are going to struggle to find something without turbos.
Maintenance/problems with shaft drives.
- Thread starter Murv
- Start date
Floating Preferably
New member
Ok Murv, FWIW I will lob my tuppenceworth in the mix. Shafts are less fuel efficient, but as you said it is shafts or nothing. However, they are a fraction of the maintenance cost that outdrives demand. I have had two boats with shafts, sequentially over a period of 34 years. the seals to keep the wet stuff out are pretty basic, whatever type you have. The ones stuffed with the ropey stuff and grease are simple, and so are my current ones with two regular oil seals with a split between which is bronze bushes and grease surrounded by a water jacket, this small assembly 'floats' on a flexible rubber tube which obviously sits the water side of the bearing carrier. They are generally reliable. Cutlass bearings should last for many years, I have replaced one pair (twin engines, so both replaced once) on my current boat in 28 years, approx 2000 hours and the boat sits in soft mud twice a day except on serious neaps. Shafts need to be removed to replace Cutlass bearings but their removal and replacement is tedious rather than technically difficult, although getting couplings off can sometimes be challenging. Like all jobs on boats, they can be awkward due to accessability and vary from dead easy to to very frustrating dependant on your boat. So go ahead , buy your boat, get to know it, and enjoy it. Best of luck.
Greg2
Well-known member
Not much more that I can add here. We have had both outdrives and shafts and there is no question that shafts are simple and require little maintenance. Assuming all is good with cutlass bearings and stern gland packing you could go for years with no maintenance and even when it is required it is relatively straightforward.
Outdrives? Not so much but then you already know that
Outdrives? Not so much but then you already know that
Murv
Well-known member
Thanks for that Trevor, apologies, I missed your post.
That's an extremely useful insight into what could go wrong, and the potential costs.
It's actually quite reassuring that even in the worst case scenario, costs are on a par with outdrive replacement, and then once done, should give many Years service.
But, checking the drive system carefully on any potential new boat should give us a fighting chance of improving our usage/repair ratio from the off
Certainly haven't seen anything normally aspirated so far! But, that's one ideal that I am happy to drop. In a small cruiser, turbos probably are preferable to give reasonable efficiency I would think, it just seemed ideal to have one less thing to go wrong.
Thanks very much! I'm very much liking the recurring theme of "many Years service"
"Many days service" would be a huge step up at the moment, so I'm more than happy (ecstatic, actually) to lose fuel efficiency as a trade off!
Murv
Well-known member
Not much more that I can add here. We have had both outdrives and shafts and there is no question that shafts are simple and require little maintenance. Assuming all is good with cutlass bearings and stern gland packing you could go for years with no maintenance and even when it is required it is relatively straightforward.
Outdrives? Not so much but then you already know that
Superb
I really just wanted to see what problems shafts could give to decide whether to just give up on boating altogether. It's a very reassuring thread, far more positive than my engine one, anyway! Bandit
Well-known member
Outdrives are about 22 to 25% more efficient than shaft drives.
Outdrives cost about the same to service as the engine they sit on, do not skimp on outdrive servicing or it will cost more in the long run.
Twin shafts, assuming full cutless bearing in the P bracket and a half one in the stern tube:
Assuming you can see the cutless bearing from the front ( you can almost all) inside the P bracket, you can remove prop and pull them out with shells and a puller, shells are like a split tube that sits outside the shaft butt against the end of the cutless bearing and the shells run inside the p bracket. This is about 6 to 8 hours work for a good fitter.
The upper cutless bearing wears very little but to replace it required the shaft to be removed to do so.
Assuming the engine alignment is good lower cutless bearings should last about 4 years.
If the boat is kept in a harbour with bad barnacle or hard growth on the shaft and not used regularly the wear will be much faster on the cutless rubber.
The movement for a good cutless bearing should be less than a mm
The stern gland for insurance reasons if a traditional packed type , draw shaft every 5 to 7 years and remove stuffing box clean out , inspect and if in good condition replace packing and reassemble, while shafts are out inspect carefully for bends ( if required spin in a lathe to check for truth) dye pen crack test in way of key way to prop if required. While the shaft is out fit new cutless bearings.
I have had stuffing boxes which need to slowly drip to enable cooling and there fore a wet engine room bilge, I have had Deep Sea Seals which scare the **** out of me and I had them removed and binned, my preference is Tides Marine seals.
Outdrives cost about the same to service as the engine they sit on, do not skimp on outdrive servicing or it will cost more in the long run.
Twin shafts, assuming full cutless bearing in the P bracket and a half one in the stern tube:
Assuming you can see the cutless bearing from the front ( you can almost all) inside the P bracket, you can remove prop and pull them out with shells and a puller, shells are like a split tube that sits outside the shaft butt against the end of the cutless bearing and the shells run inside the p bracket. This is about 6 to 8 hours work for a good fitter.
The upper cutless bearing wears very little but to replace it required the shaft to be removed to do so.
Assuming the engine alignment is good lower cutless bearings should last about 4 years.
If the boat is kept in a harbour with bad barnacle or hard growth on the shaft and not used regularly the wear will be much faster on the cutless rubber.
The movement for a good cutless bearing should be less than a mm
The stern gland for insurance reasons if a traditional packed type , draw shaft every 5 to 7 years and remove stuffing box clean out , inspect and if in good condition replace packing and reassemble, while shafts are out inspect carefully for bends ( if required spin in a lathe to check for truth) dye pen crack test in way of key way to prop if required. While the shaft is out fit new cutless bearings.
I have had stuffing boxes which need to slowly drip to enable cooling and there fore a wet engine room bilge, I have had Deep Sea Seals which scare the **** out of me and I had them removed and binned, my preference is Tides Marine seals.
blueglass
New member
Precisely my own brief on my last boat purchase and one brought about by years of being bled dry with outdrive issues large and small. Never regretted it and would never consider outdrives again unless a brand new boat. No amount of outdrives higher efficiency can compensate for the sheer hassle and expense of O/D problems on older boats. KISS every time.
Alpha22
Active member
Everything is proportional to the boat size and value.
Annual service costs for a 2 year old high performance Bravo leg are going to be far greater than an old Enfield leg. Similarly shafts on a 45' shiny sports cruiser are going to cost a shed load more to deal with than my old tub.
I predominantly boat on fresh water so don't see the wear on my cutless bearings as a significant issue. I would expect to see 10 years plus from them. P bracket cutless replacement is reasonably DIY, you may have to beg/steal/borrow/make a puller.
Old stern glands, are a DIY repack every few years, some designs appear to last longer than others between maintenance.
Conversely.....
Older boats on legs appear to be a constant drain on finances.... there is always some seal or other that needs replacing, cones and clutches wear out and need deep pockets to replace. Then there is the occasional 'oops' OMG my leg is full of water problem....
Don't even mention bellows.....
Shafts are generally more robust than legs. I know folk that regularly take the ground on shafts. Drying out on sand and soft mud. I have churned out of a muddy shallow river mooring with my solid bronze props and P brackets and seen aluminium props on legs folded up and mangled from the same mud.
Although it is simpler to change a dinged prop on legs and easier to clear weed from a prop on legs, props on shafts don't get dinged as easily or appear to suffer from weeding up the same as legs....
Annual service costs for a 2 year old high performance Bravo leg are going to be far greater than an old Enfield leg. Similarly shafts on a 45' shiny sports cruiser are going to cost a shed load more to deal with than my old tub.
I predominantly boat on fresh water so don't see the wear on my cutless bearings as a significant issue. I would expect to see 10 years plus from them. P bracket cutless replacement is reasonably DIY, you may have to beg/steal/borrow/make a puller.
Old stern glands, are a DIY repack every few years, some designs appear to last longer than others between maintenance.
Conversely.....
Older boats on legs appear to be a constant drain on finances.... there is always some seal or other that needs replacing, cones and clutches wear out and need deep pockets to replace. Then there is the occasional 'oops' OMG my leg is full of water problem....
Don't even mention bellows.....
Shafts are generally more robust than legs. I know folk that regularly take the ground on shafts. Drying out on sand and soft mud. I have churned out of a muddy shallow river mooring with my solid bronze props and P brackets and seen aluminium props on legs folded up and mangled from the same mud.
Although it is simpler to change a dinged prop on legs and easier to clear weed from a prop on legs, props on shafts don't get dinged as easily or appear to suffer from weeding up the same as legs....
omega2
Active member
not much to go wrong and easy to fix.
get one or two you will pleasantly surprised, we "inspect/antifoul" bi-annually.
The pictures show a full service, of the set up the previous "refit" was ten years back.
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Murv
Well-known member
I think we've been as thorough as we could be in servicing the outdrive.
The last service consisted of throwing it in the bin and putting a new one on.
That was 11 Months and less than 100 Hours ago, so maybe I need to do that at 6 Monthly intervals instead of annually!
Anyway, I'm not going to start another outdrive debate. I know they work fantastically well for lots of people, they give great maneuverability, are economical, can be lifted at the push of a button etc but they're not for me
Thanks for all the help on shafts, it's been very enlightening to learn what's involved with them.
I know I'm a bit sad, but I just want to say, that's a stunning looking prop Omega2! I had no idea a propeller could look elegant, but yours truly does!
It's very reassuring to see the tools involved that even I can use easily, too!
The last service consisted of throwing it in the bin and putting a new one on.
That was 11 Months and less than 100 Hours ago, so maybe I need to do that at 6 Monthly intervals instead of annually!
Anyway, I'm not going to start another outdrive debate. I know they work fantastically well for lots of people, they give great maneuverability, are economical, can be lifted at the push of a button etc but they're not for me
Thanks for all the help on shafts, it's been very enlightening to learn what's involved with them.
I know I'm a bit sad, but I just want to say, that's a stunning looking prop Omega2! I had no idea a propeller could look elegant, but yours truly does!
It's very reassuring to see the tools involved that even I can use easily, too!
Flynnbarr
Well-known member
Non turbo boats with ford 120hp shafts off the top of my head.
Broom 35 European
Birchwood 33
Freeman 33 sedan/sport
Princess 37
Senior sheer line 32
Rlm Riviera 33
Princess 33 twin 80hp
There is probably many more!
Broom 35 European
Birchwood 33
Freeman 33 sedan/sport
Princess 37
Senior sheer line 32
Rlm Riviera 33
Princess 33 twin 80hp
There is probably many more!
Murv
Well-known member
gordmac
Well-known member
My boat has two 120hp shaft drive Fords, they are very agricultural! I suspect more modern turbos would be a better option in a lot of ways.
Flynnbarr
Well-known member
Alpha22
Active member
Freeman 32...... some 108hp some with 120hp
hlb
RIP
I've almost sunk a boat on drives, but also one on shafts. The one on drives, I put up the beach in Strangford lock.
The other on shafts, I had been complaining about to the mechanic for three years. He did bits and bats but never got to the problem.
The engine mounts were broken. So the engine took the shaft out and the stern gear. Lucky rescue by the RNLA.
The other on shafts, I had been complaining about to the mechanic for three years. He did bits and bats but never got to the problem.
The engine mounts were broken. So the engine took the shaft out and the stern gear. Lucky rescue by the RNLA.
oldgit
Well-known member
]
Without wishing to be contentious, etc...
Old outdrives are constant source of trouble and the older they get the worse they are.
Shafts are a simple concept and are far more reliable in both the long and short term.
Outdrives by their very nature have to be extremely complicated pieces of kit.
You only have to count the sheer numbers of bits to alter the direction of drive (thrice) and the number of methods needed to keep water out and oil in.
Bits of rubber to keep water out of the drive via transom.
Bits of rubber to keep water out of the gearshift.
Bits of rubber to keep water out of the gearbox.
bits of rubber to get the exhaust out.
Not forgetting more rubber to keep water out of the steering fork.
Despite the vastly greater number of shaft driven boats you very rarely ever see any posts regards gearbox failure, the maintaince on which usually boils down to checking the oil levels every so often.
Even a worn cutless bearing can usually wait until the next time you do your antifoul.
omega2
Active member
=
+1
]
Without wishing to be contentious, etc...
Old outdrives are constant source of trouble and the older they get the worse they are.
Shafts are a simple concept and are far more reliable in both the long and short term.
Outdrives by their very nature have to be extremely complicated pieces of kit.
You only have to count the sheer numbers of bits to alter the direction of drive (thrice) and the number of methods needed to keep water out and oil in.
Bits of rubber to keep water out of the drive via transom.
Bits of rubber to keep water out of the gearshift.
Bits of rubber to keep water out of the gearbox.
bits of rubber to get the exhaust out.
Not forgetting more rubber to keep water out of the steering fork.
Despite the vastly greater number of shaft driven boats you very rarely ever see any posts regards gearbox failure, the maintaince on which usually boils down to checking the oil levels every so often.
Even a worn cutless bearing can usually wait until the next time you do your antifoul.
+1
Spi D
...
Sterndrives are the manufacturers' Pension Plan - alone scheduled maintenance cost-a-lot. Just this week a friend in Sweden had a repair following a leaking bellow: £5000 including labour etc.
Insurance premiums and conditions often are worse for sterndrive boats (in this part of the world it is not 'often', rather 'always').
Insurance premiums and conditions often are worse for sterndrive boats (in this part of the world it is not 'often', rather 'always').
fisherman
Well-known member
22 years and 16000-ish hours, changed the cutless once about 1996, tighten the stern gland weekly, repack about once a year. I know of a very few fishermen who have tried outdrives, and none who tried to continue with them.