What size is your motor?
My Nissan is an 8HP with and 8.5 pitch prop. I went to check for a 7.0 pitch
and they want $ 75 for a new prop. My understanding is that any good prop shop
can change the pitch of your existing prop .5" to 1" up or down... So you
could go from an 8.5 to a 7.5 pitch prop for about 35 bucks. Most engine mfgs
recommed you reduce pitch by .5" until you get the right pitch for your needs
and avoid over-reving engine. Once you reduce pitch do not use motor on
smaller or lighter boats as you will burn the engine...
Hope this helps for those of you that cannot get a smaller pitch prop.
Thanks for the sail slug distances. I made a printout for my file... It makes
a difference.
Best
SF
BTW: Pitch = distance traveled per revolution... In my case I would go to a
smaller pitch to get more power (thrust) and move slower at idle speed.
In a message dated 99-01-19 14:45:42 EST, TiffanyD@phibred.com writes:
<< Subj: RE: Nissan/Tohatsu propellers
Date: 99-01-19 14:45:42 EST
From: TiffanyD@phibred.com (Tiffany, Doug)
To: ej@tx3.com ('Eric Johnson'), wwpotter@tscnet.com ('West Wight Potter Mail
List')
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My new Nissan has a #8 Prop. Here is the table in the owners manual:m If
you can't read this let me know, I'll scan and send.
light <<--------------------------------->>Heavy Boats
Size 9 8 7
Size (mm)200 x 229 200 x 200 200 x 178
D x Pitch 7.9 x 9.0" 7.9 x 7.9" 7.9 x 7.0"
ModelOpn Short Long Extra Long
(Transom Height)
Doug
-----Original Message-----
From: Eric Johnson [mailto:ej@tx3.com]
Subject: Nissan/Tohatsu propellers
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Hey i was on nissan marine's web site and see there are 3 different props
available for the 5HP. I haven't checked, but I'm 90% sure most of us have
the middle one. (7.2" pitch).
http://www.nissanmarine.com/techtalk/prop.html has the chart
I don't know much about props, but it seems to me from what I've read on
that site and others that our boats (which are relatively heavy for what 5hp
motors use typically used in) might benefit from a 7" prop. I know the
difference in speed between half and full throttle is minimal, so maybe a
smaller pitch would help us fight the waves when the going gets rough. Any
comments?
Anyone know a dealer that sells nissan/tohatsu props cheap? I could probably
use a spare anyways, so I should try the experiment.
>>
<< Subj: Re: Nissan/Tohatsu propellers
Date: 99-01-19 17:19:12 EST
From: DAVID_KAUTZ@HP-Sunnyvale-om5.om.hp.com
To: ej@tx3.com
CC: wwpotter@tscnet.com
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You can calculate whether or not you have the correct propeller. See the
web page at: http://www.geocities.com/Yosemite/Forest/2727/calculate.html
to get the math and a good explanation. There are a number of other
interesting equations there as well (horsepower req'd to reach hull speed,
capsize ratio, etc....).
I've communicated with the Nissan tech representative via email a couple of
times about propellers. Their big concern is that a customer will over-rev an
engine by using a propeller with too small a pitch. I expect that the
standard
prop. is a largish pitch to give the manufacturer plenty of protection.
The quick summary is that you want a small enough pitch so that you are in
the
power band rpm (indicated in the engine specs.) at your cruising speed (hull
speed?) but not so small that the engine will over-rev at full throttle
Hope this helps,
Dave Kautz
P-15 #1632 "Tilly Lucy"
Palo Alto, CA
>>