Beneteau 40 2008 replacement rudder bearings - SeaKnots2024-03-29T14:55:48Zhttp://seaknots.ning.com/forum/topics/beneteau-40-2008-replacement-rudder-bearings?groupUrl=beneteau4043&commentId=900123%3AComment%3A224484&x=1&feed=yes&xn_auth=noRobert, I'm afraid your 43 is…tag:seaknots.ning.com,2017-01-03:900123:Comment:2244842017-01-03T20:52:35.931ZMike Brownhttp://seaknots.ning.com/profile/MikeBrown
<p>Robert, I'm afraid your 43 is a different model. The 40/43 this forum is made up of were introduced in 2007/08. That's not saying the discussion on rudders isn't helpful though.</p>
<p>Mike</p>
<p>Robert, I'm afraid your 43 is a different model. The 40/43 this forum is made up of were introduced in 2007/08. That's not saying the discussion on rudders isn't helpful though.</p>
<p>Mike</p> hi i have an 87/89 43 whats t…tag:seaknots.ning.com,2017-01-02:900123:Comment:2243842017-01-02T20:48:22.197ZRobert Squirehttp://seaknots.ning.com/profile/RobertSquire
<p>hi i have an 87/89 43 whats this brace you're talking about my boat keeps wandering and i have to keep correcting</p>
<p></p>
<p>hi i have an 87/89 43 whats this brace you're talking about my boat keeps wandering and i have to keep correcting</p>
<p></p> Interesting summary. Perhaps…tag:seaknots.ning.com,2016-10-28:900123:Comment:2235932016-10-28T01:20:39.906ZMike Brownhttp://seaknots.ning.com/profile/MikeBrown
<p>Interesting summary. Perhaps another call to Beneteau to discuss your results? <br/> Mike</p>
<p>Interesting summary. Perhaps another call to Beneteau to discuss your results? <br/> Mike</p> Ok further information: if an…tag:seaknots.ning.com,2016-10-27:900123:Comment:2233292016-10-27T03:28:20.239Zsail abroadhttp://seaknots.ning.com/profile/sailabroad
<p>Ok further information: if anyone is still interested?</p>
<p>Today with the help my engineering mate we tested the bearings.</p>
<p>First of all beneteau insist that all rudder strengthening modifications for my boat have been done at the factory: There is a thorough bolted cross beam that looks like it replaces the metal bolt on bracket that was retrofited for problem boats( the metal bracket that fits between the quadrants) I tried to obtain the metal bracket from Beneteau but they…</p>
<p>Ok further information: if anyone is still interested?</p>
<p>Today with the help my engineering mate we tested the bearings.</p>
<p>First of all beneteau insist that all rudder strengthening modifications for my boat have been done at the factory: There is a thorough bolted cross beam that looks like it replaces the metal bolt on bracket that was retrofited for problem boats( the metal bracket that fits between the quadrants) I tried to obtain the metal bracket from Beneteau but they wouldn't sell me it repeating that all necessary modifications have been done.</p>
<p>OK first test: Insert emergency tiller, I pulled on rudder shaft while the engineer watched from inside the boat.<br/> Results: No obvious signs of any bearing wear, no movement at all in relation to support structures.However!! The rudder support structures flex and move a lot, my engineering mate had never seen anything like it before, and he has a considerable amount of experience over many years, across many different boats.</p>
<p>Second test: I dived and really hauled on the rudder at the tip and he watched and filmed:<br/> Results: No signs of bearing problems, however again a serious amount of flex and movement from the steering support structures. When I watched the video it was disturbing, worrying.</p>
<p>We couldn't transfer the video to my tablet but will I do the test again and get my girlfriend to video, if possible I post here or link to the video.</p>
<p>The engineer checked for any detachment or lamination problems with the support structures, and there is none, all looks in excellent condition, nothing broken, separated or cracked all is well.</p>
<p>He also suggested that although there is a lot of movement it looks to be doing what is is supposed to, just that it flexes A LOT. We discussed possible modifications to stiffen it up, and decided on a slight modification to easily monitor the loading while underway, if the steering structures are getting a hammering then perhaps we should change trim or engine rpm etc.</p>
<p>One concern for me is the bottom bearing, where the steering tube joins the hull, it's glassed in, as this is a rigid connection the fiberglass must get cycled millions of times weakening it? each time the support structures flexes?!</p>
<p>Hmm I will look at that bit again in the next few day.</p> My pleasure!tag:seaknots.ning.com,2016-10-13:900123:Comment:2233192016-10-13T02:19:25.323ZMike Brownhttp://seaknots.ning.com/profile/MikeBrown
<p>My pleasure!</p>
<p>My pleasure!</p> I forgot to say thanks Mike f…tag:seaknots.ning.com,2016-10-13:900123:Comment:2235852016-10-13T02:02:21.201Zsail abroadhttp://seaknots.ning.com/profile/sailabroad
<p>I forgot to say thanks Mike for the contact numbers for beneteau, they were very helpful.</p>
<p>I forgot to say thanks Mike for the contact numbers for beneteau, they were very helpful.</p> I check rudder play every tim…tag:seaknots.ning.com,2016-10-13:900123:Comment:2232032016-10-13T01:48:58.101ZMike Brownhttp://seaknots.ning.com/profile/MikeBrown
<p>I check rudder play every time the boat is hauled, which is every summer. I give it a good push and pull but suspect no where near the pressure you put on it. So far so good but I'll definitely check it a bit closer the next time she's out.</p>
<p>Mike</p>
<p>I check rudder play every time the boat is hauled, which is every summer. I give it a good push and pull but suspect no where near the pressure you put on it. So far so good but I'll definitely check it a bit closer the next time she's out.</p>
<p>Mike</p> Drop a big concrete block nea…tag:seaknots.ning.com,2016-10-12:900123:Comment:2235492016-10-12T22:31:48.356Zsail abroadhttp://seaknots.ning.com/profile/sailabroad
<p>Drop a big concrete block near the rudder of any B40/B43 as a measuring reference and pull really hard on the rudder and I bet beer you see similar figures, 30,40,50mm Flex, it's not dead play from the bearings something else, not sure what, everything is plexus-ed together, perhaps that? Perhaps I pulled hard enough to flex the boat in the cradle?!</p>
<p>When I first got our B40 I compared the measurements I got to a hellberg-rassy in the yard which had none at all and a full skeg rudder…</p>
<p>Drop a big concrete block near the rudder of any B40/B43 as a measuring reference and pull really hard on the rudder and I bet beer you see similar figures, 30,40,50mm Flex, it's not dead play from the bearings something else, not sure what, everything is plexus-ed together, perhaps that? Perhaps I pulled hard enough to flex the boat in the cradle?!</p>
<p>When I first got our B40 I compared the measurements I got to a hellberg-rassy in the yard which had none at all and a full skeg rudder which had a small amount of play in the bearings but no "flex".at that time I don't think there was any play in our bearings at all.</p>
<p>I just checked an old B38 here in Panama which has a large amount of play, it was obvious that the shaft was moving in the log, I'm not saying ours is ok but with the b38 it is clear it needs immediate attention, the owner was oblivious.</p>
<p>I'm going to ask the marine engineer anchored a few boats down if he can take a look while I haul on the rudder, he has 35years as a chief engineer and has been through, was it 16 boats!</p> Wow looks like you found the…tag:seaknots.ning.com,2016-10-12:900123:Comment:2235482016-10-12T19:29:48.239ZMike Brownhttp://seaknots.ning.com/profile/MikeBrown
Wow looks like you found the answers. I find it strange that new 12mm is acceptable. I would think new would be zero or close to it and that the 12mm would be the indicator that it's time to repair it. Clearly the play you measured is well beyond normal. It's easy to understand why you're concerned.<br />
As for the quadrant the 40/43 had a retrofit introduced early on that was designed to strengthen the area where the quadrant met the hull. I think I mentioned that in an earlier post. Not sure it's…
Wow looks like you found the answers. I find it strange that new 12mm is acceptable. I would think new would be zero or close to it and that the 12mm would be the indicator that it's time to repair it. Clearly the play you measured is well beyond normal. It's easy to understand why you're concerned.<br />
As for the quadrant the 40/43 had a retrofit introduced early on that was designed to strengthen the area where the quadrant met the hull. I think I mentioned that in an earlier post. Not sure it's the same potential issue you mentioned above.<br />
The steering cables should be snug with some but very little play in them. The idea is to have them snug enough to provide tight steering but not so tight they'll cause stress on the cables connections, pulleys, etc.<br />
All in all it sounds like you're facing a major repair on the bearings. Good luck and let us know how it goes.<br />
Mike Reporting in with more nforma…tag:seaknots.ning.com,2016-10-12:900123:Comment:2235842016-10-12T15:27:49.108Zsail abroadhttp://seaknots.ning.com/profile/sailabroad
<p>Reporting in with more nformation:��</p>
<p>(1) I talked to a marine engineer he had some VERY interesting bits of information about rudders.</p>
<p>He told me there should be NO play in the bearings any AT ALL, any is out of spec.</p>
<p>He fixed a loose bearing on one boat, underway, by inserting a plastic Coke bottle, it has lasted several thousand miles and is still OK!</p>
<p>He suggested the [lower] autohelm arm's through shaft bolt is critical and should be replaced or a clamp added,…</p>
<p>Reporting in with more nformation:��</p>
<p>(1) I talked to a marine engineer he had some VERY interesting bits of information about rudders.</p>
<p>He told me there should be NO play in the bearings any AT ALL, any is out of spec.</p>
<p>He fixed a loose bearing on one boat, underway, by inserting a plastic Coke bottle, it has lasted several thousand miles and is still OK!</p>
<p>He suggested the [lower] autohelm arm's through shaft bolt is critical and should be replaced or a clamp added, a fail is catastrophic from the leverage if the rudder drops onto the top quadrant.</p>
<p>A very recent beneteau rudder failure was caused by resonance from the propeller amplified buy loose steering cables that destroyed the bottom bearing housing causing a slowish leak.</p>
<p>In a thousand miles the shaft might go through 80,000 cycles, but bearing failure isn't normally unpredictable, so the play will slowly increase to the point there is a mechanical failure - replace early or check regularly.</p>
<p>(2) I talked to Beneteau tech support:</p>
<p>12mm is the maximum play allowable on a NEW beneteau at the bottom rudder tip. Old boats: "If you can feel any movement of the rudder shaft IN the shaft log then it's time to sort out the problem"</p>
<p>Perhaps it's the bearings, could also be the shaft is warn thinner, the shaft log itself has been ovaled or one of many other factors.</p>
<p>"The quadrant and autohelm arms don't have published torque settings for the through and clamping bolts". I forgot to ask about cable tension.</p>
<p>Scary! It is obvious that the torque is critical as both arms clamp the rudder shaft, to much torque crushes or weakenes the (hollow) rudder tube to little and the rudder is only held by the through bolts.</p>
<p>(3) Measurements I made when the boat was 5 years old are very! surprising - in light of the spec beneteau provided of 12mm! Perhaps my figures were contaminated by the force I used (blade flex?)or the way I did the measurements?! Hmm not sure..</p>
<p>Rudder dimensions:<br/> shaft = 500mm (between top and bottom bearings)<br/>
blade = 1600mm (below bottom bearing to tip)<br/>
Total length = 2100mm</p>
<p>Fore-aft play: = 51.15mm(bottom tip)<br/> When pulled really hard and held under tension. calipers used.</p>
<p>Side-to-side play: = 42.21mm<br/> Pulled as hard as possible, loverly assistant using calipers.</p>