PROPS AND RPMS

JESSIELSMALL

Petty Officer 2nd Class
Joined
Mar 15, 2006
Messages
112
CAN SOME ONE TELL ME DO I HAVE TO GO UP OR DOWN IN PITCH TO RAISE MY RPMS AND SPEED. I HAVE A BAYLINER CIERRA AND AT FULL THROTTLE ITS ONLY RUNNING AT 3200 RMPS AND EVERY BOAT AROUND PASSES ME LIKE IM STANDING STILL. CAN ANYONE GIVE HELP.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: PROPS AND RPMS

To increase rpms you would reduce the prop pitch.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: PROPS AND RPMS

Before you spend your hard earned bucks on props, make sure the engine is running properly and that the tach is accurate and that you are not lugging around water soaked foam flotation material. Make sure the bottom of the boat is clean and free of scum and scale build up. Its amazing how much bottom fowling will slow you down. Keep in mind that while decreasing pitch will indeed raise the engine RPM (roughly 400 RPM for each 2-inches of pitch) speed will remain the same but you won't be lugging the engine. On the flip side, once the engine is allowed to rev a little more freely, you may actually pick up some speed.
 

ParallaxBill

Petty Officer 1st Class
Joined
Aug 27, 2006
Messages
341
Re: PROPS AND RPMS

Silvertip mentions;
"and that you are not lugging around water soaked foam flotation material"

Not trying to hijack this thread but how can this be determined other than cutting the deck and checking what's under the flooring? I have another plug in the bilge that connects to this space but it is stuck, at the moment.
I suspect my Glassmaster may have this problem although I know it's a heavy boat any way.

Thoughts?
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,786
Re: PROPS AND RPMS

Best way is to weigh it. Seems mfgr's make available the dry weight of their boats and you can add your own for add on's.

Mark
 

ParallaxBill

Petty Officer 1st Class
Joined
Aug 27, 2006
Messages
341
Re: PROPS AND RPMS

Ah, good idea and one I hadn't thought of.

Great info here, thanks. :)
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: PROPS AND RPMS

Of course in order to obtain an accurate dry weight of the boat you would either have to strip it of any extra rigging including the engine or be able to obtain an almost exact weight of the engine,rigging, and all other add on equipment and subtract to determine whether a few gallons of water are hiding within the hull.Then there's the give or take factory weight fluctuations.

I think I'd work at removing that stuck plug and perform a visual.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,786
Re: PROPS AND RPMS

Ok, there is another thread on boats or ob non repair that the owner suspected water. He said he drilled a small dia hole in the lower center of the transom and stuck a piece of wire in there whereupon he found foam, and it was dry. Said he pushed the wire in about a foot in the test. He didn't say it, but I bet he was thrilled.

Mark
 
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