[Public-List] Propellers...

[via Public-List]

Hello Gordon,

I am very curious to know how you found your first full season with your new propeller?  I have a two bladed original which is somewhat unresponsive and was intrigued at the start of the year by your experience.  (noise, vibration reduction, power in reverse, strain on the old A4) I would certainly enjoy hearing if you are still happy if you are inclined to share your thoughts!

cheers,

Maurice
Avoca 322

  


---- Original Message ----
From: Gordon Laco via Public-List <public-list at lists.alberg30.org>
To: George Dinwiddie <gdinwiddie at alberg30.org>; Alberg 30 Public List -- open to all <public-list at lists.alberg30.org>
Sent: Sun, Jun 5, 2016 11:44 am
Subject: Re: [Public-List] Propellers...

Thanks,Caroline laughed at me over the battery charger/charge state thing.  When Inoticed it had clicked off, I assumed a malfunction so went into 'grumpyGord' mode.... 'damned thing, what next, knew something would go wrong, hatebatteries, when I am going to find time to fix this, probably five thingswrong, not just one...' etc etc  until I realized that the issue was thatthe batteries were indeed fully charged...On 2016-06-05, 11:11 AM, "George Dinwiddie via Public-List"<public-list at lists.alberg30.org> wrote:> Sounds like a complete win, Gord.> > On 6/5/16 10:42 AM, Gordon Laco via Public-List wrote:>> Hello friends,>> >> I¹m sorry to reintroduce this topic... But I¹ve changed propellers and>> thought I¹d share the experience.>> >> Some of you may recall that I have pontificated about taking a Œdon¹t>> change¹ position with regard to the prop supplied by Whitby Boatworks with>> the Atomic IV engines many of our boats have.>> >> Well this spring I was thinking about the engine and decided to try a>> change.  Last fall¹s ŒMisery Trip¹ reached a crescendo of suffering with a>> slog to windward in 40 knot winds and a sharp chop...  We were nearly>> stopped a few times, mostly by wave action, but SURPRISE trudged along and I>> would say coped better than our companion¹s boats which were all fin keeled>> yachts fitted with diesels.    So power delivered to the water wasn¹t the>> issue... What I was thinking about was alternator performance and cooling.>> >> Cooling has never been an issue with our engine, particularly since I>> replaced the old water pump with the upgrade offered by Moyer.  However I¹ve>> been keenly aware that our cruising RPM of about 1000 doesn¹t really spin>> things down in the engine compartment fast enough to deliver what the>> alternator is theoretically capable of.>> >> I liked the look of the narrowed bladed ŒCampbell¹ props I¹d seen on other>> boats, and liked the idea of increasing revs while at least keeping the same>> Œpower in the water¹ situation the stock two bladed prop gave us.  So I>> ordered the Campbell which they recommend for Alberg 30¹s fitted with Atomic>> IV engines with 1:1 transmissions.    The vendor said he was certain what>> shaft diameter and taper my boat has... But because I¹m a doubter, I sent>> him my old prop for reference.>> >> In due course the new prop came back along with the old one (and he was>> right, he did already know the specs).  I couldn¹t wait to try it out.>> >> We installed the new prop as part of my condensed spring outfitting (and no,>> I did not do the cap rail job I wrote about earlier.  I got busy with work>> which took me away most of April and May so that¹s that on that job for>> now).  Eagle eyed Rod saw the shiny new thing and commented ŒI thought you>> said...¹     Well I know what I said, but what the heck...>> >> We got SURPRISE into the water and after securing the rig, started up and>> started the two hour trip back to our sailing club.  First thing I noticed>> was that I seemed to have a lot more power in reverse than before.  The>> second thing was that prop walk seemed to have dissappeared... Amazing.>> >> The only negative comment I¹d read about these props on line referred to a>> supposed loss of maneuvring power... But I was able to do the usual spin>> within her length that SURPRISE normally does.    Motoring out of>> Dutchman¹s Cove Marina, I found that our speed at idle was lower, and that¹s>> a good thing of course not unexpected because of the finer pitch.  Once out>> past the breakwater, we opened the throttle and both Caroline and I were>> amazed.  Boat speed climbed to 6.6 knots as usual for full throttle, but>> there was no roar and vibration from the engine.  I won¹t say it was as>> quiet as electric, but the change from how things were was startling and>> dramatic.   We were so quiet at full speed I mistrusted the knotmeter and>> fired up the GPS, but it confirmed the speed.  Amazing.>> >> We found our old cruising speed of 5.2 at 1000rpm was now 5.2 at 1400 (this>> second RPM was full out open throttle with the old prop). Yes the engine was>> spinning faster, but at the same throttle setting and clearly not labouring>> quite so hard.   The boat was so quiet we didn¹t feel like we were moving,>> so we did the trip at 6+.>> >> So the prop change is rated a total success.  But there was a surprise in>> store for us.  Because I was away so much I didn¹t do my usual thorough>> recharge of the batteries... We started up after launch on what was left in>> the batteries after the Misery Trip and months of winter lay up.   I was>> glad there seemed to be enough juice to spin the engine.>> Yesterday I decided to connect up the battery charger and run it all day...>> But after only moments, the charger was indicating full charge.  I assumed a>> problem with the charger but after investigating, realized that the>> Œproblem¹ was that the battery bank was indeed fully charged and the>> automatic function on the charger was sensing this and shutting off.>> >> How could that be, I thought... Then it occurred to me that the alternator>> must have run up the batteries on the trip over from the marina.  In the old>> days, the alternator barely kept up with the engine¹s requirements and I¹d>> had to charge from shore power periodically.  So it appears that whatever>> was in the batteries at launch, the engine itself topped them up in the 90>> minute shot over under power (wasn¹t two hours because we galloped home>> faster).>> >> Happy happy.>> >> Gord #426 Surprise_______________________________________________These businesses support your Association:http://www.alberg30.org/store/A30supporters.htmlPlease support them._______________________________________________Public-List mailing listPublic-List at lists.alberg30.orghttp://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org