330 performance dropping

[fishie1]

Buddy has 2002 330 with F225s. Cruising speed and top end have both decreased about 3mph (from ~25 to 22) over the last season and a half or so. Props were re-worked at the beginning of last season and he was told by the prop shop that they were fine at the beginiing of this year. The prop shop is highly regarded. However, other than an additional coat of bottom paint there really is no other change from year to year to affect the performance so we're thinking the problem has to be related to the props. He is considering a new set of SWS 15 1/4 X 17s, same as the originals, hoping that he will regain the 3mph.

Does this sound like a reasonable course of action?

 

[pablor]

Marine growth would do that. May be a mid season bottom clean?

 

[ocnslr]

Even a slightly fouled bottom could have that much adverse impact.

I can notice decreased performance with some barnacles on the bottom of the trim tabs.

And perhaps the additional coat of bottom paint was rolled longitudinally, instead of fore and aft.... leaving lots of ridges to spoil the water flow.. :?

Brian

 

[catch22]

E-10 fuel?

 

[B-Faithful]

Hot summer air. My boat is faster in the cool spring and fall air.

 

[jehines3]

1000lbs of gear, water, and fuel in my boat make a 2knt difference. I have lightened the boat allot this season and it's made a world of difference. Before I was burning 15gph/motor at 22 knts (4100rpm), now 12.5gph/motor at 25.5knts (4100rpm). I also got a fresh new bottom over the winter. Each build up coat of bottom paint adds 75 or so pounds. Go through every tackle drawer and storge space on the boat and see how much junk you'll find. I still keep all my fishing gear on, but not the assortment of lead and other seasonal junk I found. My shed is full my boat is not. jh

 

[HDGWJOE]

Marine growth would do that. May be a mid season bottom clean?

that would be my guess as well...

 

[fishie1]

Props were the answer. Seatrialed the boat last night with brand new Saltwater Series props and the boat picked up about 4 knots :shock: at cruise. Sounds better, rides better, planes better, fuel economy is better, making us wonder how bad the old props could have been. Plus they're nice and shiny :lol:

 

[BobP]

Was old prop(s) bent as in hitting something ?

Can't see how stainless prope will wear out of change shape on their own, or change shape over time.
Somehow damaged, yes.

New props are SW Series II, are old ones Series I?

 

[Bob's Cay]

What about the hubs on the old props. Any possibility they were slipping?