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  • #6587
    Webmaster
    Participant

    Hi folks,

    Any ideas on a high pitch whine from the saildrive from about 1200 – 1800rpm. I have been told that it comes from the prop cavitating!! and a cure is to ‘sharpen’ the leading edge of the prop. The boat is a B44 and is a dream apart from the whine.

    #8713
    Webmaster
    Participant

    When we bought our bavaria 34 Christmas 2001 the manual for the sail drive specified engine oil for the lubricant. Ours had a very high pitched whine. About end of 2002 there were articles advising that the lubricant should have been automatic transmission fluid. We checked this out with Volvo and changed to ATF and the whine disappeared.
    Lots of posts on this site at the time.

    #8716
    Webmaster
    Participant

    @spencerd wrote:

    I have been told that it comes from the prop cavitating!!

    Would not be my first impression… unless you were getting other symptoms too….. vibration, lack/dip in propulsion etc.

    #8722
    Webmaster
    Participant

    I recently replaced the saildrive rubber seal and when I asked for the oil to refill the sail drive I was advised by Volspec that it had been changed to automatic transmission fluid, so I bought the required amount and filled the saildrive. On a recent trip to Lymington I bought repalcement oil and fuel filters and asked for a litre of the ATF to keep as a top up for the sail drive. I was informed by a very helpful assistant that Volvo had just issued a warning about using ATF in their saildrives following several cases of gearbox lockups in reverse, which had beed diagnoised as a failure in the lubrication. I immediatley drained the ATF and replaced it with the original spec engine oil. Be warned if you have had no problems with the original oil then stick to it do not change it for ATF.

    Pax

    #8724
    Webmaster
    Participant

    @Pax wrote:

    Be warned if you have had no problems with the original oil then stick to it do not change it for ATF.

    Pax

    It depends which saildrive you have whether it requires engine oil or ATF; my 120SE, for instance, requires ATF).

    The definitive(?) Volvo document matching saildrive type and oil recommended is http://www.volvopenta.com/SiteCollectionDocuments/Penta/Misc/drive_1_oil_rec_7745608.pdf.

    #8725
    Webmaster
    Participant

    My saildrive on my B32 is a MS25s and Volspec were adamant that the lubrication specification had recently been changed to the ATF even though the handbook stated engine oil (as does the listing on the link, although it is dated 2006). I still reckon if it’s worked ok in the past don’t change it, stick with what you know to be working.

    Pax

    #8728
    Webmaster
    Participant

    Thanks for all your replies, but the saildrive oil has been changed to engine oil and i believe that the problem lies with the prop as under 1000rpm the drive is silent and over 1800rpm the same. There is no vibration at all and does 7.5kts at 1800rpm but I would like to travel slower without the high pitched note from below!! Will change the prop to a folding one and hope that will make the difference.

    Thanks again one and all.

    #8741
    Anonymous

    2007 37 fitted with the standard 2 blade aluminium prop. It is the prop. There is a Volvo bulletin issued to dealers about changing the edge of the prop. I had mine done by Volspec and the noise disappeared.

    Having now had the coating come off leaving a raw paint edge, the noise is back. I’m pretty sure it has nothing to do with the gearbox or oil as I have never heard of a gearbox failing. See another recent thread by me – ATF was specified for the 2007 D1-30. It is now 10w 40 engine oil due to possible clutch problems. ATF and engine oil do mix I am told. Some ATF gets left in the box when changing to 10W 40.
    I’ve had this confirmed by 2 Volvo agents.

    If you put your ear to the hull bottom or aft cabin sole you can clearly hear the whine but not with your head in the engine compartment.

    #8848
    Webmaster
    Participant

    @spencerd wrote:

    Any ideas on a high pitch whine from the saildrive from about 1200 – 1800rpm. I have been told that it comes from the prop cavitating!! and a cure is to ‘sharpen’ the leading edge of the prop. The boat is a B44 and is a dream apart from the whine.

    It is indeed due to cavitation. I did an experiment, being towed close behind the boat watching the propeller – not for the faint hearted! As the revs got to the critical point, a mass of bubbles appeared like a vortex behind the propeller; it actually looked quite stunning. All was cured by a new propeller, after the old one got damaged.

    I had tried altering the leading edge, but I was told by Volvo Penta to blunt it, not sharpen! I think it would be best to get definitive profile information before proceeding.

    #8956
    Webmaster
    Participant

    Further to my previous posts, I picked up the boat again in September and low and behold no prop whine. I donned goggles to find that the prop was covered in barnacles and bits of weed, (thats what 4 months of Med does).

    This would then suggest that it was the props cavitation setting up a horrible harmonic. Good to know that it was not the gearbox. Probably will purchase a folding prop when the boat comes off of charter. And by the way the performance of the prop led to a marked decrease in boat speed. Will let you know if the whine returns in May 2012 when the boat returns to the water.

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