Prop thoughts (Narrowed down my choices) Revolution4 vensuraor enertia
BruceM wrote:
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)
"Short Wave Sportfishing" wrote in message
...
On Sun, 22 Apr 2007 14:41:03 -0700, Josh Assing
wrote:
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.
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
I hae a four blade on my ETEC - I would never go back to three blade
props.
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
|