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  Topic Review (Newest First)
07-07-2011 02:06 AM
paul323 I am also in SF (South Bay).

Spinning the prop does not help - strange but true. The barnacles grow regardless.

Over summer, as the water gets warmer, you need to clean the prop/bottom about every month. If you don't race, and don't mind knotmeter and depthsounder failing, a couple of months. Over winter, 2 or 3 months wait is fine.

I clean every month May-October, and a couple of times over winter.

To prevent major fouling and bottom cleaning, either clean regularly, or go spend a week in the Delta. The fresh water kills off all those saltwater critters!
07-06-2011 11:32 PM
serenity440 I was only making 1.5-2.5kt on a 9 kt boat and figured fouling...Had the prop. and bottom dove on and all resolved.

My question is, how quickly does this growth occur and what can you do?

I know it depends on the conditions (warmer waters) and the boat (more complicated hardware) but wonder about avoiding such major fouling. I left the boat for 4 months in SF bay and expect that is where it all occurred.

Should you spin the prop once a week, month or what to prevent major fouling?

07-05-2011 09:54 PM
Alive3and3Well Black smoke can mean anything from clogged fuel filters to a restricted exhaust elbow to clogged injectors...everyone here is willing to share their knowledge and experience. The more history and symptoms you can supply the better everyone can help.

Good luck!
07-05-2011 08:51 PM
harpguitar Hey Guys,

I may have missed this part. Why would black smoke be a sign of a fowled prop or hull?

So I had the boat hauled today and the hull didn't look too bad but there were clearly barnacles on the prop and prop shaft.

Otherwise the prop looked good and the zinc was still there (a little of it anyway).

But why the black smoke?

07-04-2011 08:17 AM
sck5 cleaning the prop will make the biggest difference for the least amount of effort. If you are hauling the boat you can finish the rest of the bottom when it is out of the water. (but dont let it dry out first - as others have said you will then need a jackhammer to get them off)
07-03-2011 10:08 PM
sawingknots the bottem and prop is the most likely problem but there could be others too,if cleaning,checking doesn't solve plz give us a report
07-03-2011 09:54 PM
boatpoker I have a 9' Aquapro inflatable with aluminum bottom and an 8hp Suzuki. She'll do 28mph with a clean bottom. I left her in the water for two weeks and the slime on her bottom prevented her from getting on plane....Scrubbed the bottom.... back to 28mph
07-03-2011 08:08 PM
CalebD It is surprising how a small amount of barnacle growth on a prop can mess with a prop's pushing and pulling power or thrust.
07-03-2011 06:10 PM
sawingknots bottem growth is usually the culprit,especially bad if your boat is not taken out often also i've noticed that some areas tend to be worse than others
07-03-2011 04:03 PM
harpguitar Thank you. It makes sense to check for some sourt of fouling of the prop and hull first. It is hard to believe that it could slow me up so much but given the numbers you presented and the fact that my boat hasn't been cleaned for two years maybe that is the answer. Am getting it towed tomorrow as it doesn't seem to have enough power to safely manuever around other boats. This is one of those moments when an outboard would be nice.

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