Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

[fpdiver]

Hi,

Brand new owner of a 2003 1903 CC with a 125HP Merc Salt Water Carb Classic. On our first couple runs we are only getting to about 4300 RPM. I strongly suspect that we have too high a pitch for the way we are loading the boat (3-5 adults will be typical).


So,

I am curious what other people have on their 1903 CC's (or similar)...a 1903 weighs about the same at an 1802 and a 2006 and a 2401.


(I think our present prop is a 15" Diameter by a 21" pitch. This is on a marina report...have not confirmed)

I have looked at the merc prop calculator and that says something like 13x17 or 13x19.

thanks

 

[springhead]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

fpdiver
I have a 2004, 1802, with the same motor as you.
a 125 saltwater and the prop is supposed to be a 21 pitch,
I bought my boat new in 04 from the dealer and has since discovered it actually has a 19 pitch.
look at the pitch, the number is on it.
good luck David

 

[fpdiver]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

Dave,

Thanks. The boat is in the water right now. I am basing the prop size on the previous owner's service records.

Are you able to reach 4800RPM with 3-4 people and your 19P prop?


thanks

Frank

 

[springhead]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

Frank,
I can reach 4800 no problem with 3 or 4 people as long as there not 300 lb people.
I also on a perfect
flat day with just one other person have got my boat to
48 mph.
full trottle of course.
one other thing my buddy has a 06 1902 and needed to have his prop
changed out this year, the dealer sad it wasnt the right one for his motor.
ill find out what he went to,
i went with him last monday and his boat was running awesome
he needed to get more rpms and now he has it,
David

 

[fpdiver]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

thanks for your help. I will try to not fall off the back of my boat this weekend leaning over to try to read the prop numbers and will post them on Monday.


thanks

 

[tomysel]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

I'm pretty sure your WOT rpm should be much higher than 4800.(Check your motor specs.) I think it should be more like 5700. If your only getting 4800 then your motor's working too hard and you definitly need to lower your pitch.

My optimax 150 is rated at 5250-5750 at WOT.

 

[tomysel]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

Sorry just looked it up and you should be able to hit 5250 at WOT at your normal load...

 

[frankie g]

Re: Help with Prop Diameter/Pitch for '03, 1903 CC 125HP

Talk to Ken at Prop Gods...he'll set you up right. http://www.propgods.com/forum/default.aspx?g=forum