Antifouling!

Portofino said:
It’s this important imho detail PeteM needs a strategy to deal with , even say a 3 week gap between visits in the season .
You can,t keep realistically and ball achingly keep organising the “ free “ lift or what ever @ SCM amongst the 3 syndicate members .
You know take a flyer arrive late Fri Pm , then have to wait until Monday , if it’s not a Sp Bank hole or the lift operator is “ off “ or the lift is having “ maintenance “
Long W/E - home Tue etc ——- canning those KAD ,s with fouled props = big bills arriving any time soon !

It’s either hire a diver
Or somebody’s gotta hand clean them .
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Porto, the boat seems to be OK for a few weeks between visits and if the props had some light fouling on them then I think it could be quickly removed with a brillo pad from the bathing platform. I doubt that a bit of fouling on the upper section of the leg would be that critical.
 
Portofino said:
:)
Transom which is presumably in a lot of shade should look a lot cleaner , no worm casts ( or what ever they are ? ) - just slime at the most .If it’s been parked up a few months prior to its annual lift ?

@ least JMF has a pic of the product allegedly put on which tally’s with his instructions, and presume reconcile s with any invoice —— if he wasn’t there personally to oversee the job .
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Difference between my boat and jmf's boat is that his has a hi/lo platform and mine doesnt so transom on my boat comes almost to the aft end of the bathing platform and is more exposed to light. Also the way my boat is parked the transom faces SE so it gets a lot of sunlight and that makes it an ideal cultivation patch for fouling
 
MapisM said:
Beware, that's usually a symptom of some degree of cavitation. Look out for tipping in that area.
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Yes I realise it’s the energy released from micro * vapourisation of the water that’s blasts off the accretions .
Question is is it planned / controlled / calculated / harmful ?
As of yet no visible harm being done to the metal

While we are on the subject , just curious about your comment on Hurricanes props .
Big subject , can end up a cat skinning excerise :)

Hurricanes are 5 blades in a heavey slow planing boat but with high torque v12,s
I note the leaves seem to overlap and appear high pitch .

As speed of the vessel through the water increases ,it’s my understanding that there becomes a point that the actual number of leaves start to create drag .
Talking fully submerged not surface piecing .
So as you go faster you want fewer leaves .
The overlap too , great for using low down torque at slow speeds to use max fwd thrust effect , but once above said speed the overlap creates drag too .Too much metal now getting in the way of the flow basically.

So it depends on the intended use - as always
Mine are high pitch ( can be a pita manoeuvring) ,cos high torque engines , a FL Targa 47 has a lot smaller engines for eg
4 blades — I think there’s a better chance / ease of balancing a 4 over a 5 in theory! Practice may be different?
And a smaller overlap in fact no overlap at all of the leaves so minimise drag - let water pass through over a certain through the water speed .

So really I think every prop , different as they are , are matched to the boats ,
Put Hurricanes, “ best prop seen so far “ shape on my boat correctly sized dia wise ( not the exact same ) or put suitable more performances oriented like mine ( again suitable dia ) and I think they will produce adverse results .

Aimho
 
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Ignoring aesthetics (comments for which are always welcome!), I note that M99 also comes in white (whereas M77 is not available in white). The boat currently has white and my inclination is to go white again. I've never been keen on blue (particularly not royal blue) but I would consider grey.

However, I wonder that consequences would be of applying a grey eroding A/F on top of a hard white A/F. Would the white start to show through and is this a bad thing (cosmetically) or good thing (indicates that its getting thin / patchy)?
 
petem said:
Porto, the boat seems to be OK for a few weeks between visits and if the props had some light fouling on them then I think it could be quickly removed with a brillo pad from the bathing platform. I doubt that a bit of fouling on the upper section of the leg would be that critical.
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Just the props Pete ,
Wait until the water warms up and the sun is full strength for the critters ,they thrive .
Just passing on experience.
 
petem said:
Ignoring aesthetics (comments for which are always welcome!), I note that M99 also comes in white (whereas M77 is not available in white). The boat currently has white and my inclination is to go white again. I've never been keen on blue (particularly not royal blue) but I would consider grey.

However, I wonder that consequences would be of applying a grey eroding A/F on top of a hard white A/F. Would the white start to show through and is this a bad thing (cosmetically) or good thing (indicates that its getting thin / patchy)?
Click to expand...

Black works best .
This is what the all professional s tell me and advise .
It’s does,t really matter why .
Tried white on the SS , against advice , went to blue , better , ended up with an inevitability with black .

Welcome to the Med AF club :)
 
petem said:
Ignoring aesthetics (comments for which are always welcome!), I note that M99 also comes in white (whereas M77 is not available in white). The boat currently has white and my inclination is to go white again. I've never been keen on blue (particularly not royal blue) but I would consider grey.

However, I wonder that consequences would be of applying a grey eroding A/F on top of a hard white A/F. Would the white start to show through and is this a bad thing (cosmetically) or good thing (indicates that its getting thin / patchy)?
Click to expand...
You're over worrying!
But white is no good unless it is eroding. It looks crummy in drone photos when you're planing because it goes greeny/slimey
I agree w Porto: black looks best
 
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MapisM said:
What a/f did you have on those props, none at all, as I understand?
And if so, how long did it take to get to those conditions?
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Yup, none at all. That pic is my springtime lift out, maybe April, after a year in the water and after a winter when the boat goes to sea once a month for "exercise" when the sun is out, but doesn't do a lot of time/miles underway, so the barnacles have good opportunity to grow. The yard I use sprays hydrochloric acid and then a strong jet wash, and it all comes off easily

BTW I also do not antifoul the inox H+B hilo platform lift mechanism
 
petem said:
I doubt that a bit of fouling on the upper section of the leg would be that critical.
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No reason to have any doubt about it.
In outdrive (or outboard) powered boats, any fouling above the cavitation plate, no matter how bad, is irrelevant to the performance at planing speed.
Mind, keeping the whole leg clean is a good idea anyway, if you care about its conditions.
It's amazing how barnacles seem to be able to eat aluminum, if you give them enough time... :ambivalence:
 
jfm said:
Yup, none at all. That pic is my springtime lift out, maybe April, after a year in the water and after a winter when the boat goes to sea once a month for "exercise" when the sun is out, but doesn't do a lot of time/miles underway, so the barnacles have good opportunity to grow. The yard I use sprays hydrochloric acid and then a strong jet wash, and it all comes off easily

BTW I also do not antifoul the inox H+B hilo platform lift mechanism
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Yup, I guessed that you didn't bother antifouling that mechanism, which btw shouldn't affect the boat performance for the same reasons of my previous reply to petem.
Otoh, I'd expect those props to make life a fair bit harder for the engines.
Do you have any idea about how much is the speed loss (and/or the load and egt increase, if by chance you checked that on your displays) vs. clean props?
 
Portofino said:
Put Hurricanes, “ best prop seen so far “ shape on my boat correctly sized dia wise ( not the exact same ) or put suitable more performances oriented like mine ( again suitable dia ) and I think they will produce adverse results .
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Don't worry PF, the virtual cigar I awarded to hurricane props was among those "posted so far in this thread", most of which are related to somewhat similar boats, btw.
Dismissing the props of your boat (whose shape btw I can't for the life of me remember) was not my intention by any stretch of imagination! :D
 
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MapisM said:
Otoh, I'd expect those props to make life a fair bit harder for the engines.
Do you have any idea about how much is the speed loss (and/or the load and egt increase, if by chance you checked that on your displays) vs. clean props?
Click to expand...
Oh yes, for sure. I don't run long cruises with props like that, and even after lift/antifoul in March/April I lift again in August the day before I go to Corsica etc for a long cruise. Or get a diver. The lift is e1000 and the diver e200, but the lift is better because it is nice to have a clean hilo mechanism for swimmers etc.

In winter I just stay local, a few miles at d speed mostly, so the bad condition of the props does not hurt the engines.

When the props are like that, top speed would be off by 5 knots and fuel burn would be something like 20 litres/mile rather than 15/16. I wouldn't run it at P speed for more than a brief moment, though of course the c32 is the strongest engine in its class and the one best able to take "abuse", having 1.5x the dimensions and displacement of the MAN/MTU 1500-1600bhp engines. But anyway it is perfectly ok and there is no "abuse" at D speed
 
Aha, I see. All understood and agreed, including your last statement ref C32 vs. MAN.
Now that I got to know MAN engines a bit better, thinking that they are now pushing up to 1900hp out of their V12 block is almost a practical joke, when compared to the C32...
 
Well, I suppose the only fair comment could be "show me a man, and I’ll show you a crime"... :rolleyes:
It's a pity that LS1 is not around the asylum lately, because he surely could write you a book on this whole subject.
Me, all I can say just having seen both the C32 and the MAN V12 blocks in flesh, is that the latter tuned to give the same output as the first is pushing the envelope to say the very least.
 
MapisM said:
Aha, I see. All understood and agreed, including your last statement ref C32 vs. MAN.
Now that I got to know MAN engines a bit better, thinking that they are now pushing up to 1900hp out of their V12 block is almost a practical joke, when compared to the C32...
Click to expand...

Agreed that seems a lot of power from a relatively small block but I guess the attraction for boat builders is that the MAN V12 is relatively lighter than the C32 (not sure whether that translates into lower cost) and of course lightness adds speed. Actually I've got to liking the MAN V12s in my boat. Touch wood I've never had a problem with them and they give smooth torquey performance. But as you commented on another thread, the thought of those 96 little valves whizzing up and down, any one of which could really ruin my day, does keep me awake at night sometimes:eek:
 
There are soooo many variables from taking a solid road / truck / locomotives block , upping the output then marinising it .

If you read the link above , I get issues with cooling instal from Sunseeker and there a suggestion / blame handed about regarding inadequate warm up time as well .
I don,t think there are any FL 78 , owners with the same issues , handing out “ abuse “?
Also another bit of goss —— unlike our MAN,s which have arguably a keen cooler strip down clean regime - for ever .

Latest CAT policy is chuck away coolers after say 5/7 years apparently one of them ,I think it’s the charge air corrodes from the inside and eventually goes .
So they have rewritten the service book to change out - whole part

JFM I understand s has retro fitted a freshwater flush system on his boat ,so presume that may extend the life .
MAN coolers are happy sat in seawater — sure may salt up buts that’s taken care of in the service schedule.

Re block size / relative weight , - jury’s still out for me —- instinctively bigger - more iron the better .
Buy to counter that appart from the obviously extra kg,s , I,am thinking heat distribution.
In a high stressed variant some % grater out put than was originally intended in a liesure boat then cooling is king to longevity.— that’s accurate targeted cooling by the fluids on both sides it becomes critical and hot spots can develop in the marine vs that’s not manifested on the lower powered road vs .
The more extra iron hanging about the less control over the hot spots ,it’s the differential heat distribution that’s leads to cracking - so big is not necessary best as it’s born out ^^^ in the link
Things are not allways what they seem

On a different subject of the iron work / block dims —- look at the D12 - highly regarded on here — except one tiny little detail the pan leak .
Nip up the bolts - New gasket , - new pan etc ——
Nope what’s actually hapening is the block twists under load .
The H shaped webbing can,t cope with the 715 / 800 or what ever it’s now asked of .

So yup I would be a bit scarred if the new C32 with 1900hp was able to keep cool for long enough in use ,if not a new block / head s
And if the latest MAN 24 L V12 pushing 1900 Hp was using the same block as the 1390 , 1550 Hp variants .

Around 2000 Hp I would be looking at MTU V 16 ,s ——— even more valves to loose sleep about :)
 
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