How long do bellows last?

Thepipdoc

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I bought my first boat in July this year – Searay 270, it has twin Mercruiser 4.3l engines with Alpha legs.
From the service documents and receipts that came with the boat I can see that the bellows were last changed in September 2007.
The boat is kept permanently salt water and since buying taking ownership I have done about 70 hours and I'm guessing that shes done about 100 hours since the last leg service.
My questions are – How often should the legs be serviced and how long can I expect the bellows to last? Is my understanding correct that if the bellows should split or perish then it’s about as damaging for an engine as it is if a cambelt snaps? A bloody expensive repair!
Finally what sort of price can I expect to pay for a service of the legs and should changing the bellows be included in the service?
As always ... thanks in advance.
 
Your operators manual should tell you the frequency of changing the bellows but likley to be every 2 years. The cost and implications of split bellows (including a sinking risk) just ain't worth trying to make them last longer.
How much you pay for a service will depend on what you specify -bellows? anodes? change oil etc
 
My last boat had a single merc v6. Bellows change every 3 years cost about £300. Engine and drive every year cost for both approx £300.

Enjoy the sea ray just sold mine on the hunt for another.
 
The 4.3 V6 is a very easy engine to service if you fancy doing it yourself. About £100 in parts per engine/drive and a day or so work. Mainly involves changing the oil, filters and greasing the greasy bits. Whilst the boat is out of the water you can inspect the bellows, but they shouldn't need changing yet. The money you save on DIY will pay for an afternoon's petrol. :D
 
Mymobo is correct. You are on borrowed time after 3 years. Also the bellows will last better if you store the boat with the drive in the down position. Less UV can get to the bellows and less strain on the rubber / spring.

A leaky UJ bellows on an alpha will wreck your gimbal bearing, UJs. possibly the drive and allow water into the bilge.

A split in the shift cable bellows will sink the boat in very quick order.

Exhaust bellows failure will not have drastic consequences other than noise.
 
Two years tops if she is afloat all the time,even a tiny weep/split will cause expensive stuff later,no need to panic as a month or three either way will probably be neither here nor there.
 
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I understood they should be inspected every year and changed every 2 years.

I am fairly sure this is the service schedule.

I guess, if the boat sinks due to a failed bellows and you cant prove it was serviced in line with the manufacturers schedule, the insurance company wont pay out. i.e. They would argue negligence.
 
I understood they should be inspected every year and changed every 2 years.

I am fairly sure this is the service schedule.

I guess, if the boat sinks due to a failed bellows and you cant prove it was serviced in line with the manufacturers schedule, the insurance company wont pay out. i.e. They would argue negligence.
The Mercruiser service schedule I've got says inspect every 100 hours or annually. It does not say anything about changing every 2 years. This year I changed the shift cable and bellows, the old bellows were in perfect condition and did not look worn at all. This is on a 7 year old boat.

Mind you if a bellow splits, my boat isn't going to sink as its kept on its trailer in the yard. If one were to split out at sea, then its WOT towards the nearest beach James Bond style. :D
 
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