Prop thoughts (Narrowed down my choices) Revolution4 vensura or enertia
Thanks to all -- who helped with my initial question.(Current: 22' cuddy -- HEAVY boat, 5.7 alpha1 3 blade SS, 19pitch, 4100 rpm
(should be around 4500) After poking around mercury's website, and talking to a prop shop; I've narrowed
down my choices to these: Revolution4, 4 blade 17 pitch
Vensura, 4 blade 17 pitch
Enertia, 3 blade 17 pitch I'm leaning towards the revolution4 -- but it is pricey; so I want to get a bit
of real-world, non-salesman based opinions on it. Thanks
-josh |
Josh
Apr 20
|
| I got an Apollo SS 13 1/4 X 17 it runs my little boat 40 mph with a 90
HP motor. IMHO They work great and are relatively inexpensive. Liberally Yours, 1.20.09 Fredo |
Fredo
Apr 21
|
| Anti-fouling for fast craft (racing yachts & semi-planing or planing hulls)
is available in "self-polishing" or ablutive type.
Basically this means that as the effectiveness of the application reduces,
it gets worn off (released?) until if you keep using your boat there is none
left at all on your hull. This also keeps the surface polished & very
smooth. After several years of experience you will know how heavy to apply
it to last the season & therefore reduce the ammount you need to remove
prior to next years application.
If you aren't using this type, then it WILL drag your speed down
drastically.
Look up "Interlux ablutive" in google. |
BruceM
Apr 22
|
| Or even look up "Interlux ablative" !!! ooops! |
BruceM
Apr 22
|
| Ablative -- yes; that's what I'm using.
"sluffing" is how we used to refer to it. |
Josh
Apr 22
|
| There's a lot more than just HP that relates to the speed. I have a 19pitch on
my 18' boat with a v6 and it is perfect for the boat --that same prop isn't so
good on the 22'.... I'm leaning towards a 4 blade based on some reading & information I gleemed from
"those in the business" (but not salesmen) Thanks
-j |
Josh
Apr 22
|
| I hae a four blade on my ETEC - I would never go back to three blade
props. |
Short
Apr 23
|
| The whole subject of this thread is about loads on engines with too big a
pitch.
If you don't know the consequeces of that then I suggest going to a
"propellor selection" website or listening to your reputable marine
supplier.
A boat engine endures much much more stress than an automobile engine that
goes up & down hills.
Load on a boat engine is continuous for long periods of time.
Most marine shops will tell you to find the propellor that allows desired
WOT revs & then still drop one more size.
Depending on your gearing, the load remains constant right thru the rev
range.
eg, at 20% throttle you have 90% load.
60% throttle you still have 90% load
So you can see it appears you have 105% load on yours & your motor WILL die
prematurely.
You are not one size below.
You are not equal.
You are one size over!!!
Get it?
If you don't listen ,
then be prepared for both a motor PLUS a downsize prop!!! (not to mention
excess fuel you're chewing thru) |
BruceM
Apr 23
|
| IMHO I was always told you should prop your motor for WOT RPM and
never to change the speed of the boat!
IMHO If that is a problem you should get a bigger motor. Liberally Yours, 1.20.09 Fredo |
Fredo
Apr 22
|
| Hmmmmmmm.....
The Stiletto SS 3 blade 19X17.5 on my 5.0 Mercruiser/Alpha 1 WOT is
4600. 6,000 lb 25' boat. It has been o/hauled twice in 16 years; picked
up 150 RPM from the slight change in blade profile. I'd say your motor
is not performing up to snuff, or possibly the Gear ratio in the
outdrive is wrong... Plenty of C.I. to run your original prop at 4500+,
unless the props a dog and not designed well. (probable).
JR
|
JR
Apr 20
|
| The bluewater is known for being a pig out of the hole, and incredably stern
heavy. The engine is running as good as it's going to w/o a rebuild.
No blow by, even compression. New plugs, wires, cap/rotor. Timing set. New
coil (really helped a lot) and a professional carb rebuild. The original prop was a 17 pitch; the PO got a "deal" on this 3 blade SS prop
(19 pitch) on the hope that he would get a higher top end. Thanks
-josh |
Josh
Apr 20
|
| Has it got anti-fouling on it?
If so is it self-polishing? (or what you call it in your country?)
Any sign of osmosis?
Any barnicles?
Any overweight women or fishermen?
Any excess luggage / equipment?
Excess tilt up or down?
If all that is under control then try pitch down before you kill your
chequebook. (Aust spelling!) "Josh Assing" <XjoshX@jAssing.com> wrote in message |
BruceM
Apr 21
|
| "it" being the boat, drive, or prop? Yes to the 1st 2, no to the last. |
Josh
Apr 21
|
