2120 SC DV prop question

[Legal Bill]

I have a 2004 2120 SC with a Yamaha F200. The boat came with a stainless steel 15x17 prop installed and a brand new aluminum 14 1/2 x 17 in the cabin. The stainless steel prop needs to be serviced to correct some nicks and "sanding" along the edges. I find with the 15x17 the engine is slow to get on plane and tops out around 5500 rpm. I was thinking of trying out the aluminum prop first to see if it improves performance at all, but that would have to wait till the spring. So I'm wondering what prop diameter, pitch and blade members the rest of you are running. I do know about Permatrims and raising the engine. I'm just trying to focus on the propeller in this discussion.

 

[willyk9]

Can tell you what I did with my 2320/F250

Came with stock stainless 3 blade prop, motor mounted all the way down, saw about 5400rpm max and typically run a heavy boat.

-Added SE Sport 300 foil
-Raised motor 2 holes
-Added 4 blade OSI Turbo prop and went down in pitch a little.

Saw a good improvement with hole shot, more torque in the mid ranges, better cruise MPG, stays on plane at lower speeds, only negative which was fine with me I lost 2-3mph off the top end.

 

[Legal Bill]

Thanks.

 

[shawnee83]

Plug your numbers into this for some options. My F225 with the same prop only wants to do about 5800 WOT most days depending on load and current. This is of course Trimmed out as much as I can.
http://www.yamahapropselector.com/propSelector/web/

 

[Jday]

I have a 2004 dvsc and run a 200 mercury optimax with an 3 blade enertia 15 x 15; raised motor and permatrim. WOT is about 5700+ and running in the upper thirties with three people and 1/2 a tank of gas. Rpm's and speed are approximate, just going from memory. The boat jumps on plane and does not run with the bow real high, much lower than when I first got the boat. At cruise, 37-3800 rpm I'm going 27 mph and burning 2.7 gph.

 

[Jday]

Sorry, that's 2.7 miles per gallon

 

[scubaclint]

I have a 2003 2120 SCDV with a HPDI 200HP. I use the boat for scuba diving 80% of the time, even with 3 divers we'll have up to 10 tanks, weights, gear, etc = heavy load. I went with a 14.75" Diameter X 15" pitch 4 blade. Gets out of the hole great with a load, planes 14-16 knts at 36-3800rpm, cruises nice at 21-23 @ 42-4400rpms.
I don't like WOT (with an older 2-stroke!) but have had it over 30 at 5400 on the bay and still had throttle left. Also have the SE Sport 400.
With a heavy load and the daily wind chop here in SoCal the 4 blade is perfect for me. I got the Solas aluminum prop since it had a nice price point and now that I know I like it I'll upgrade to SS in the spring. Didn't want to drop the coin and not like it. The aluminum one will make a good spare.
No idea about fuel, no flowmeter...I just close my eyes at the pump and accept the price of freedom to dive where I want to!

 

[Makakio]

I have a 2003 2120 SCDV with a HPDI 200HP. I use the boat for scuba diving 80% of the time, even with 3 divers we'll have up to 10 tanks, weights, gear, etc = heavy load. I went with a 14.75" Diameter X 15" pitch 4 blade. Gets out of the hole great with a load, planes 14-16 knts at 36-3800rpm, cruises nice at 21-23 @ 42-4400rpms.
I don't like WOT (with an older 2-stroke!) but have had it over 30 at 5400 on the bay and still had throttle left. Also have the SE Sport 400.
With a heavy load and the daily wind chop here in SoCal the 4 blade is perfect for me. I got the Solas aluminum prop since it had a nice price point and now that I know I like it I'll upgrade to SS in the spring. Didn't want to drop the coin and not like it. The aluminum one will make a good spare.
No idea about fuel, no flowmeter...I just close my eyes at the pump and accept the price of freedom to dive where I want to!

Hey Clint - similar use/water situation up here in Santa Cruz, but repowering to newer Yam F200 (4-cyl) shortly and considering props (currently a 3-blade). Do you think same prop would work? Or is there something different about the power delivery of a 2-str vs 4-str that would mean a prop change.

 

[gman1001]

Can tell you what I did with my 2320/F250

Came with stock stainless 3 blade prop, motor mounted all the way down, saw about 5400rpm max and typically run a heavy boat.

-Added SE Sport 300 foil
-Raised motor 2 holes
-Added 4 blade OSI Turbo prop and went down in pitch a little.

Saw a good improvement with hole shot, more torque in the mid ranges, better cruise MPG, stays on plane at lower speeds, only negative which was fine with me I lost 2-3mph off the top end.

Willyk9, What pitch OSI prop did you go with? You mention going down a little. I have a new to me 2300DV with a terrible prop. I'm exploring options to reprop. I have the same motor as you and like you, have little interest in top speeds.

Tx!

 

[fisher]

call prop gods

 

[willyk9]

Willyk9, What pitch OSI prop did you go with? You mention going down a little. I have a new to me 2300DV with a terrible prop. I'm exploring options to reprop. I have the same motor as you and like you, have little interest in top speeds.

Tx!

I'm going to say the stock 3 blade was a 19p and I went with a 17p OSI

 

[Brent]

Set motor height with anti ventilation plate skimming water surface when on plane, and load boat with crew, full gas and gear. Next, prop to max rpm.

check with Ken abPtopGods.com and check his forum