As the weather has been rubbish lately i decided to get 'Sorcerer' out the water for a check and bit of maintenance. The antifouling is good but the shaft anodes have completeley gone, vanished, flown off, whatever. I had the bonding of the shafts, props etc, checked by a marine engineer and everything is fine and he says I don't need them anyway. Why fit them then? I have been told they are the first thing to go but after about 7 months??? What does everyone else think? Do you have shaft anodes?
Also, there seems to be some play in the cutlass bearings in the P brackets which gives a knocking noise if you lift the shafts up and down. I have now had three people, including the engineer, tell me they should be replaced. As the boat has only done about 60 hours and everything seems perfectly aligned I am a little concerned!! Surely they should last a hell of a lot longer than that!!??
if you don't have this noise or vibrations when sailing, let it be as it is.
Last year I put a new cutlass bearing in Tommie's strut. It had 0,75 mm play on the new 45 mm shaft. The company where I bought it told me it needed 0,75 mm play as a water film would carry the shaft. They had not even a bearing of 45,10 mm where I asked for. When in the water there was a vibration in the boat above the strut and directly I blamed the bearing, lifted Tommie out bought a 1 3/4 bearing who is 44,45 mm and widened to 45,05 mm. When back in the water, much less but still a vibration and the first hour the bearing produced a noise like our cat when you step on his tail.Lifted Tommie out again and brought the new prop to a balancing company. Still vibrations but only above 1500 prop shaft rpm. This spring I checked underwater for barnacles and found cavitation spots on the prop (due a to small prop blade area ???) so the bearing had nothing to do with the vibrations after all.
I do not use shaft anodes as everything is bonded back to the bar anodes including the shafts. They are always the first things to erroded away and can cause problems spinning loosely on the shaft until they drop off!
I think perhaps you should replace your cutlass bearings now rather than have to have another lift out if one fails later on. It is certainly worth rechecking the alignment as the mounts are now settled in but when back in the water. Maybe the shaft anodes or remains of have slipped down and damaged the cutlass bearings.
I have not been able to measure the amount of play in my cutlass bearings yet but it certainly seems a lot more than 0.75mm and makes a distinct knocking when you lift the shafts up and down.
I must admit to being a little confused as to whether or not there should be any play in them as some people say there should be none and some say a very slight amount, like you said about the water film carrying the shaft.....I don't know which is right.
I have had some clanking noise from the couplings since the boat first went in the water but only on tickover, that goes as soon as the revs come up and more load goes on. They are due to be changed this week, at last.....!
Yes you are correct that the shaft anodes have spun on the shaft. The port side had obviously slid down to the P bracket before falling off but fortunately had not caused any damage to anything.
I would feel a lot happier replacing the cutlass bearings and I am waiting for my boatbuilder to come and check them out. He says there was play in them from the start, as did kees in earlier message, but it does seem excessive to me and others that have seen them, after such a short space of time!
Will re-check alignment when back in the water as you say, although everything there seemed ok.
'Sorcerer' is now back in the water after some fresh antifoul and a polish. The cutlass bearings were not replaced. I had another engineer and my builder check them and they said they were absolutely fine. My builder actually said (and I can understand what he means) that because the shafts are perfectly aligned with the cutlass bearings in the P brackets is the reason for a slight amount of slack. An 8 thou feeler gauge would only just about go in and they were the same as when she was first launched. He said that on another boat, that they had not built, the shafts were really tight in the P brackets because they were misaligned and you could'nt turn the props by hand.....mine turn quite easily! Anyway, I have stopped worrying about it and getting on with using her now! Just need to catch some fish.
Just need to catch some fish
