Suggestions for maintenance tasks on shaft driven boat

RIN

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Just got the boat out of the water for an annual spruce up. We have had outdrive boats for many years so perfectly familiar with the tasks to undertake generally on the boat and particularly on the outdrives.

However we now have a twin shaft driven boat (Jeanneau Prestige) and were wondering what we need to do with the sterngear. I've ordered the anodes and I guess burnishing the props and rudders is one thing - any suggestions on the easiest way to do that? Neither the rudders or props were painted. Is it worth doing that?

Is there anything else we should do to the sterngear before it goes back in the water? At the moment it looks like we will have some time on our hands which is good news
 
Ah, the ex outdrive boat owner. The boat has been lifted and you don't know what to do with yourself now you haven't got to service your egg whisks. If the cutlass bearings are ok just sit back and enjoy all the extra time you now have. :D
 
Ah, the ex outdrive boat owner. The boat has been lifted and you don't know what to do with yourself now you haven't got to service your egg whisks. If the cutlass bearings are ok just sit back and enjoy all the extra time you now have. :D

+1 Yep, I agree with that, lift each shaft up and down and check for play. Anything more than a few mm is excessive so may need cutlass bearing replacement.
Other than prop polishing, anode replacement (& electrical continuity testing to make sure they're working OK) and maybe shaft polishing if the shafts are exposed, spend your time polishing and admiring the hull. Oh, a couple of shots of grease in the rudder stocks is a good idea too.

Good isn't it?
 
Hi RIN,

Don't paint the props, but do anti-foul the rudders. If you have anodes on the shafts, change them. If you don't anodes on the shafts, find out why not. Check the play in the cutless bearings. If there's more than 1mm play, consider renewing them.

Piers
 
I use the Force 4 TK prop spray on the props and shafts. Not perfect but it means that all the fouling washes off with the jet wash. No polishing required.
Also check your sea cocks. We have a number of these on our Azi, and I'm sure you do too.
 
Do as advised, get them something like this, and put it back in the water, that's what boats are for. LOL

23rdjune2010LIFTOUT019.jpg
 
Inspect props for damage, corrosion or erosion, also prop nut.

Rope cutter inspect if fitted, if it has plastic bushes replace those.

Cutless bearings as Piers says no more than 1mm movement, also inspect for damage to rubber sleeve or movement or damage to sleeve.

Clean props and shafts , I don't antifoul, P Brackets, shafts, props or rudders just clean with scourers or brick cleaner if barnacled and wash off with a hose.

Inspect stern gland for damage or leaks, also water flow to gland depends on type.

Check continuity of anodes and underwater metal items.
 
As the others have said, and BTW welcome to the sensible mode of motor boating.

I use a cup brush on an angle grinder. Brings the props up like new in about 15minutes per prop, but goggles and a dust mask essential.
 
"If the cutlass bearings are ok just sit back and enjoy all the extra time you now have"

Yes but more importantly...what the hell is he going to do with all that money he is about to save ? :)
 
Well thanks guys. I am glad that I will never have to take a leg off again or worse put one back on!

Is the 1mm play at the stern glands on the P bracket? I expect there will be more if measured at the props themselves.

I only miss the legs when trying to get the back end of the boat on to an alongside pontoon. I thought I might be able to use the prop effect - but there is none. I find the only way to do it is to reverse on to an alongside berth.
 
Is the 1mm play at the stern glands on the P bracket? I expect there will be more if measured at the props themselves.

I only miss the legs when trying to get the back end of the boat on to an alongside pontoon. I thought I might be able to use the prop effect - but there is none. I find the only way to do it is to reverse on to an alongside berth.

Its one mm movement of the shaft in any direction except fore or aft. Also look for any delamination of the rubber sleeve from the shell of the bearing.

I assume you have had little opportunity to play with the shaft boat? some boats with little keel you can feel the prop walk effect others SD with a large keel less obvious. Its practice, practice, practice! With partner or mate as crew choose a quiet day traffic wise in the marina and go and play, different scenarios, port side to the starb side to then a finger bow in stern in etc. Then practice with a wind and get used to using the wind to assist you.

If you use a decent sized ball fender 1/3 of the way back from the bow with twin controls you can use this to lever the boats stern away from the pontoon and then reverse out providing the wind is not against you.
 
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When going astern, the way a particular prop rotates ,probably determines just how much prop walk can be induced .
Engaging both engines could produce very little deviation from going directly astern whereas using either port or starboard alone could achieve the desired affect.
My boat has contra rotating propellers and there is definately a marked difference in amount of sideways hull movement depending which engine is being used to go astern..............
 
Most twin shafts have outward turning props i.e. the top of the prop turns outward to its side. This produces a tendency for the port to push the bow to stbd ahead and the stern to stbd astern. The stbd is opposite. Essentially two arcs making an oval around the boat.

I have a good idiots guide that helped this idiot learn the ways of a twin shaft boat. I will PM you a link.
 
Most twin shafts have outward turning props i.e. the top of the prop turns outward to its side. This produces a tendency for the port to push the bow to stbd ahead and the stern to stbd astern. The stbd is opposite. Essentially two arcs making an oval around the boat.

I have a good idiots guide that helped this idiot learn the ways of a twin shaft boat. I will PM you a link.

Thank you I will have a look at that in the time freed up by not servicing any outdrives
 
Thank you I will have a look at that in the time freed up by not servicing any outdrives

It is always heartwarming when somebody steps into the sunlit uplands of enlightenment and joins the holy world of the simple shaft.
However always spare a thought for those deluded poor souls still wandering lost in a universe of leaking propeller shaft /gearshift seals,corroding rams,weeping steering shafts (leg off/ engine out) and the always exciting world of watching that milky foam oozing out of the drain plug again.. :)
 
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Yes but more importantly...what the hell is he going to do with all that money he is about to save ? :)

Spend it on fuel of course. Going from 2. Something mpg to 1. Something will certainly use up any savings from leg maintenance.
 
Spend it on fuel of course. Going from 2. Something mpg to 1. Something will certainly use up any savings from leg maintenance.

H,mm.
A reassuring thought for the owners of stern drives and possibly even worth considering if you spend your entire boating time at WOT from the second you undo the ropes until just before you hit the pontoon on your return.
Back in the real world,you start the boat and it idles away while you faff about doing stuff,setting up the nav gear and remembering to undo the shore power.
This will be followed by a lot of fiddling about getting out of the finger berth followed by a slow creep across the entire length of the marina to the entrance or the lock gate.
At last you are free...Err nope,there will almost certainly be a speed limit for a few miles meaning more crawling along until the chance to open those throttles wide and off we go,usually to just round the corner to a secluded cove with only you and 50 other boats,so more low speed tedium find somewhere to park and anchor without annoying all the boats around you with wash. :)
Time to sit back and relax and wonder if the trim tab indicators are reading correctly or the things have stopped working again and why one of the legs has slowly been dropping into the water since you last were on boat.:)
 

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