Avon 620 open adventurer Yamaha F115 4 stroke

Prattyboy · 17 June 2009, 08:07

Bought this bought about a month ago and loving it with the family. The only thing is when I 1st bought it it would do about 33 mph at WOT (5000rpm). A month on it is only doing about 25 mph. It is moored at a marina and there's a little growth on the hull...but would this make a real difference? The engine is 2007 still under warranty and sounds and runs fine. it has a standard 17" prop. Would going to a slightly larger prop make that much difference / damage the engine?

Cheers for any thoughts.

Prattyboy

PeterM · 17 June 2009, 08:38

I think that a months growth in the recent warmish weather is your problem. Try taking it out of the water , clean it & then see if you get the MPH back .

Chris · 17 June 2009, 09:04

2 weeks in a marina saw me loose 3 knots.

Prattyboy · 17 June 2009, 14:13

thanks for replies. Growth looks like it's fairly well advanced so will take out this weekend. Apart from pressure hose cleaning is there any solution you can recommend?

PeterM · 17 June 2009, 14:22

I find just elbow grease & a light green scouring type pad - take the growth off without scratching the gel.

codprawn · 17 June 2009, 14:30

Quote:

Originally Posted by Blackroady

I find just elbow grease & a light green scouring type pad - take the growth off without scratching the gel.

I agree - unless you have barnacles and then you need a plastic windscreen scraper.

PeterM · 17 June 2009, 14:54

Quote:

Originally Posted by codprawn

I agree - unless you have barnacles and then you need a plastic windscreen scraper.

Good point - mine live in fresh water , apart form the odd few days here & there - so never really seemed to affect me . Do barnacles even live in fresh water ? Never occured to me before !

codprawn · 18 June 2009, 02:57

Quote:

Originally Posted by Blackroady

Good point - mine live in fresh water , apart form the odd few days here & there - so never really seemed to affect me . Do barnacles even live in fresh water ? Never occured to me before !

No and it's a good way to remove them - stick the boat in fresh and it kills them off - doubt it will remove the rings they leave behind though - you need acid for that!!!

mikesyam · 18 June 2009, 05:15

My Humber needs a clean speed down from 52mph to 42mph, makes a big difference but in lazy mode at the minute.

walruz · 18 June 2009, 06:13

I use concentrated hydrochloric acid from a garening type spray can. Just spray it on leave 5 mins and wipe off with a deck scrubber. Reapply on the odd patch that didn't completely wipe off.

It is used on all the quays around the islands as well as it doesn't do any damage to the envirnment.

ian

Leapy · 18 June 2009, 06:25

Quote:

Originally Posted by walruz

[Hydrochloric Acid] is used on all the quays around the islands as well as it doesn't do any damage to the envirnment.

ian

Though you might want to be careful handling it...

...hydrochloric acid...forms acidic mists. Both the mist and the solution have a corrosive effect on human tissue, with the potential to damage respiratory organs, eyes, skin, and intestines...Personal protective equipment such as rubber or PVC gloves, protective eye goggles, and chemical-resistant clothing and shoes are used to minimize risks when handling hydrochloric acid (from Wikipedia)

So, make sure all marine life is equally protected

Prattyboy · 18 June 2009, 08:55

elbow grease and a jet spray it is then!! (think I'll give the acid bath a miss tbh!)

PeterM · 18 June 2009, 09:51

I also get a nice feeling knowing that I have nice white , clean hull under me as I accelerate on to the plane. Visions of a nice smooth flow of water etc & that that the boat looks good without a green/ brown line around it .

JSP · 18 June 2009, 12:13

It's like dragging a carpet through the water isn't it.

Jetwash and buff it up. Remember a few boats in Victoria dock in caernarfon kept the hulls very highly polished so stuff couldn't get a grip. Worked a treat too but not sure how often they had to get them polished,

codprawn · 18 June 2009, 12:24

Quote:

Originally Posted by Leapy

Though you might want to be careful handling it...

...hydrochloric acid...forms acidic mists. Both the mist and the solution have a corrosive effect on human tissue, with the potential to damage respiratory organs, eyes, skin, and intestines...Personal protective equipment such as rubber or PVC gloves, protective eye goggles, and chemical-resistant clothing and shoes are used to minimize risks when handling hydrochloric acid (from Wikipedia)

So, make sure all marine life is equally protected

Yes but that's the 100% stuff. Remember it's whats in your stomach and what burns your throat when you get reflux!!!

How quickly would a gallon of HCL dilute in about 200 trillion gallons of sea water???

Leapy · 18 June 2009, 12:30

Quote:

Originally Posted by codprawn

Yes but that's the 100% stuff. Remember it's whats in your stomach and what burns your throat when you get reflux!!!

How quickly would a gallon of HCL dilute in about 200 trillion gallons of sea water???

Don't take life so seriously, Codders. Chill out and get out on your boat more

codprawn · 18 June 2009, 13:45

Quote:

Originally Posted by Leapy

Don't take life so seriously, Codders. Chill out and get out on your boat more

I have been busy cleaning it and getting it ready - just need to bleed the steering now and clean the tubes with TFR.

Downhilldai · 18 June 2009, 18:26

Quote:

Originally Posted by codprawn

I have been busy cleaning it and getting it ready - just need to bleed the steering now and clean the tubes with TFR.

Too right! I thought your boat had been re-toobed in white when I saw it last week.