Posted by JoanJohn@… (JoanJohn@…)
PWM -
why your fourth Max Prop? Bad luck or product problems?
John Ernst
Hertford, NC - with my first Max prop
Posted by Jerome Weinraub (zayde@…>)
Alan;
I have an F33(#68)And a new,and as yet,unused Variprop,15.5".What settings did you change to?.I ordered mine as per your suggestion.I’d like to see if your settings are what the factory set mine to
----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February 19, 2006 10:18 AM
Subject: RE: [freedomyachts2003] Max Prop
I have an F-33 and found the Variprop has a very short hub. They can provide 3 or even 4 bladed and it has a number of other benefits. They also do custom sizes so the do 15.5” instead of 15 or 16 which are standard sizes (no real cost difference). I played with the pitch a bit although their calculations were usable. If you mention F-33 to Michael 804-436-0150 www.varipropusa.com fax 804-436-0140 and my name he’ll be able to look up all the specifications on mine although your 32 would be a bit different)
I’ve been very happy with it and have had it for several years.
Alan Kusinitz F-33 Hull #51 1982
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of andre lavioletteSent: Sunday, February 19, 2006 9:30 AMTo: freedomyachts2003@yahoogroups.comSubject: Re: [freedomyachts2003] Max Prop
Bob,
If you can send me the reduction ratio stamped on the I.D.plate of your reduction gear I may be able to help. It seems to me that the diameter of your prop is much to small for the engine you have . In broad and general terms, diameter is what gives you push and stopping power. Blade area is capital here. Pitch gives speed. Send also h.p. and max RPM indicated on engine i.d. plate. Weight of vessel and sailing water line length would nail it down.16 in. whether 2 or 3 blade is probably correct. Pitch would also vary vary depending on what you send.
Andre.
Bob Frew <rfrew@…> wrote:
Last year I looked at Autoprop and found out that Idid not have enough clearance. this year I called Maxprop and they will sell me a 14" 3 blade for 2240.They said that the 3gm was probeably not the originalengine. was too much power for a 14 2 blade and the 3blade would work much better. Does anyone have anopinion on this.thanks, Bob Frew, Freespirit, Freedom 32.
Find your next car at Yahoo! Canada Autos
Posted by Paul McFadden (pwhitmac@…>)
Bob, I’m running a three blade Michigan fixed blade 14X14 prop on my Hoyt 32. A three blade MaxProp will have much the same thrust characteristics (97%). You really shouldn’t go for a larger diameter prop, as you should have a minimum of 15% of the diameter of the prop clearance from the hull. Believe me, you can pitch a 14" Max so “coarse” that you’ll only get about 1200 rpm out of your engine, shortly before you do damage. FYI, I’m putting a 14" Max on when I haul in the Fall. That’ll be my fourth MaxProp. Luck, PWMBob Frew <rfrew@…> wrote: Dear Andre,The ratio is 2.62:1. The problem is the clearancewhich is 1". Thanks, Bob— andre laviolette <andrelaviolette@…> wrote:>
Bob,> > If you can send me the reduction ratio stamped on> the I.D.plate of your reduction gear I may be able> to help. It seems to me that the diameter of your> prop is much to small for the engine you have . In> broad and general terms, diameter is what gives you> push and stopping power. Blade area is capital here.> Pitch gives speed. Send also h.p. and max RPM> indicated on engine i.d. plate. Weight of vessel and> sailing water line length would nail it down.> 16 in. whether 2 or 3 blade is probably correct.> Pitch would also vary vary depending on what you> send.> > Andre.> > > Bob Frew <rfrew@…> wrote:> Last year I looked at Autoprop and found out that> I> did not have enough clearance. this year I called>
Max> prop and they will sell me a 14" 3 blade for 2240.> They said that the 3gm was probeably not the> original> engine. was too much power for a 14 2 blade and the> 3> blade would work much better. Does anyone have an> opinion on this.> > thanks, Bob Frew, Freespirit, Freedom 32.> > > SPONSORED LINKS > Sailing schools Sailing instruction > Sailing lesson Sailing course Sailing> adventure Sailing > > ---------------------------------> YAHOO! GROUPS LINKS > > > Visit your group “freedomyachts2003” on the web.> > To unsubscribe from this group, send an email>
to:> freedomyachts2003-unsubscribe@yahoogroups.com> > Your use of Yahoo! Groups is subject to the> Yahoo! Terms of Service. > > > ---------------------------------> > > > > > ---------------------------------> Find your next car at Yahoo! Canada Autos
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Posted by Paul McFadden (pwhitmac@…>)
I’ve Had four boats since 1979 and I fitted them, or in the case of my present boat, am about to fit them all with MaxProps. They are a marvelous unit, and I like boats, what can I say?JoanJohn@… wrote: PWM - why your fourth Max Prop? Bad luck or product problems? John Ernst Hertford, NC - with my first Max prop
Yahoo! Autos. Looking for a sweet ride? Get pricing, reviews, more on new and used cars.
Posted by Alan Kusinitz (akusinitz@…>)
I experimented a number of times and
currently happy with 12 pt pitch both forward and reverse. The forward appears
correct based on maximum RPM. The reverse is a matter of preference My slip
sometimes requires heading straight at it so I prefer more thrust in order to
stop although this gives more prop walk to port. If you prefer less fortunately
the Variprop allows separate reverse pitch adjustment. My transmission
reduction is 2.61 forward and 3.16 reverse. Don’t know if yours is the same.
Alan
Below is some general info from. Variprop in
case its helpful.
Re your numbered items:
(1) 1" of pitch = approx 200 engine RPM. So I would
start with 1-1/2" of pitch reduction and see what this produces in RPM
increase. I would target 3400RPM as the max. If you flatten the pitch to
get a sustained 3600RPM, your boat speed at a more reasonable crusing RPM will
be as lot slower, obviously.
(2) You can run continuously at any RPM that does not result
in (a) overheating and (b) black smoke. So if you throttle back to just
maintain say 2900 or 3000RPM, and if the engine is happy, no damage will result
even though the boat is theoretically “overpropped”.
The potential for damage begins when the throttle is opened
farther in an attempt to obtain more RPM. In this mode the engine is being
fed more fuel than it can efficiently burn, combustion efficiency is poor,
there is smoke, etc.
(3) To reduce propwalk: you can reduce the pitch in Reverse
by 1" or even 2". This will result in a decrease of thrust and
therefore of stopping power but I expect it will be a very satisfatory
tradeoff. Even with this adjustment, your VariProp will produce considerably
more reverse thrust than will a normal fixed prop.
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of Jerome Weinraub
Sent: Sunday, February 19, 2006
12:45 PM
To: freedomyachts2003@yahoogroups.com
Subject: Re: [freedomyachts2003]
Max Prop
Alan;
I have an F33(#68)And a new,and as yet,unused Variprop,15.5".What
settings did you change to?.I ordered mine as per your suggestion.I’d like to
see if your settings are what the factory set mine to
----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February
19, 2006 10:18 AM
Subject: RE:
[freedomyachts2003] Max Prop
\
I have an F-33 and found the Variprop has
a very short hub. They can provide 3 or even 4 bladed and it has a number of
other benefits. They also do custom sizes so the do 15.5” instead of 15
or 16 which are standard sizes (no real cost difference). I played with the
pitch a bit although their calculations were usable. If you mention F-33 to Michael
804-436-0150 www.varipropusa.com fax 804-436-0140 and my name he’ll be
able to look up all the specifications on mine although your 32 would be a bit
different)
I’ve been very happy with it and
have had it for several years.
Alan Kusinitz F-33 Hull #51 1982
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of andre laviolette
Sent: Sunday, February 19, 2006
9:30 AM
To: freedomyachts2003@yahoogroups.com
Subject: Re: [freedomyachts2003]
Max Prop
Bob,
\
If you can send me the reduction ratio stamped on the I.D.plate of your
reduction gear I may be able to help. It seems to me that the diameter of
your prop is much to small for the engine you have . In broad and general
terms, diameter is what gives you push and stopping power. Blade area is
capital here. Pitch gives speed. Send also h.p. and max RPM indicated on
engine i.d. plate. Weight of vessel and sailing water line length would nail it
down.
16 in. whether 2 or 3 blade is probably correct. Pitch would also vary vary
depending on what you send.
\
Andre.
\
Bob Frew
<rfrew@…> wrote:
Last year I looked at Autoprop and found out that I
did not have enough clearance. this year I called
Max
prop and they will sell me a 14" 3 blade for
2240.
They said that the 3gm was probeably not the
original
engine. was too much power for a 14 2 blade and
the 3
blade would work much better. Does anyone have an
opinion on this.
thanks, Bob Frew, Freespirit, Freedom 32.
Find your next car at Yahoo! Canada
Autos
Posted by Jerome Weinraub (zayde@…>)
They set mine at 13" fwd,11 reverse-same engine and gearbox. I bought a digital hand held tach,and I’m going to get accurate RPM readings,as I don’t trust my tach.
I’ll make a fudge chart----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February 19, 2006 7:40 PM
Subject: RE: [freedomyachts2003] Max Prop
I experimented a number of times and currently happy with 12 pt pitch both forward and reverse. The forward appears correct based on maximum RPM. The reverse is a matter of preference My slip sometimes requires heading straight at it so I prefer more thrust in order to stop although this gives more prop walk to port. If you prefer less fortunately the Variprop allows separate reverse pitch adjustment. My transmission reduction is 2.61 forward and 3.16 reverse. Don’t know if yours is the same. Alan
Below is some general info from. Variprop in case its helpful.
Re your numbered items:
(1) 1" of pitch = approx 200 engine RPM. So I would start with 1-1/2" of pitch reduction and see what this produces in RPM increase. I would target 3400RPM as the max. If you flatten the pitch to get a sustained 3600RPM, your boat speed at a more reasonable crusing RPM will be as lot slower, obviously.
(2) You can run continuously at any RPM that does not result in (a) overheating and (b) black smoke. So if you throttle back to just maintain say 2900 or 3000RPM, and if the engine is happy, no damage will result even though the boat is theoretically “overpropped”.
The potential for damage begins when the throttle is opened farther in an attempt to obtain more RPM. In this mode the engine is being fed more fuel than it can efficiently burn, combustion efficiency is poor, there is smoke, etc.
(3) To reduce propwalk: you can reduce the pitch in Reverse by 1" or even 2". This will result in a decrease of thrust and therefore of stopping power but I expect it will be a very satisfatory tradeoff. Even with this adjustment, your VariProp will produce considerably more reverse thrust than will a normal fixed prop.
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of Jerome WeinraubSent: Sunday, February 19, 2006 12:45 PMTo: freedomyachts2003@yahoogroups.comSubject: Re: [freedomyachts2003] Max Prop
Alan;
I have an F33(#68)And a new,and as yet,unused Variprop,15.5".What settings did you change to?.I ordered mine as per your suggestion.I’d like to see if your settings are what the factory set mine to
----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February 19, 2006 10:18 AM
Subject: RE: [freedomyachts2003] Max Prop
I have an F-33 and found the Variprop has a very short hub. They can provide 3 or even 4 bladed and it has a number of other benefits. They also do custom sizes so the do 15.5” instead of 15 or 16 which are standard sizes (no real cost difference). I played with the pitch a bit although their calculations were usable. If you mention F-33 to Michael 804-436-0150 www.varipropusa.com fax 804-436-0140 and my name he’ll be able to look up all the specifications on mine although your 32 would be a bit different)
I’ve been very happy with it and have had it for several years.
Alan Kusinitz F-33 Hull #51 1982
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of andre lavioletteSent: Sunday, February 19, 2006 9:30 AMTo: freedomyachts2003@yahoogroups.comSubject: Re: [freedomyachts2003] Max Prop
Bob,
If you can send me the reduction ratio stamped on the I.D.plate of your reduction gear I may be able to help. It seems to me that the diameter of your prop is much to small for the engine you have . In broad and general terms, diameter is what gives you push and stopping power. Blade area is capital here. Pitch gives speed. Send also h.p. and max RPM indicated on engine i.d. plate. Weight of vessel and sailing water line length would nail it down.16 in. whether 2 or 3 blade is probably correct. Pitch would also vary vary depending on what you send.
Andre.
Bob Frew <rfrew@…> wrote:
Last year I looked at Autoprop and found out that Idid not have enough clearance. this year I called Maxprop and they will sell me a 14" 3 blade for 2240.They said that the 3gm was probeably not the originalengine. was too much power for a 14 2 blade and the 3blade would work much better. Does anyone have anopinion on this.thanks, Bob Frew, Freespirit, Freedom 32.
Find your next car at Yahoo! Canada Autos
Posted by Alan Kusinitz (akusinitz@…>)
That’s what they calculated for mine
originally. I sent them my eventual settings but guess they still use their
calculated ones. I checked mine against RPM both on the engine tach but also
with a mechanical tach (I can’t remember the proper name but you lay it
on the engine and pull out a wire that vibrates and you adjust until the wire
appears still and that’s the RPM on the dial, very inexpensive but works
well, the digital should be great).
I think the 13 is too high for forward
(but you can always hold back a little on the throttle so its not running at
max, I don’t think 13 is way overpitched just slightly) but let me know
what you find if it differs. The problem with going too high first is that if
you power hard for long periods of time and the pitch is too high the engine
may overheat.
The 11 in reverse is probably fine but it
depends on thrust. At 12 mine stops on a dime but is pulling to port quite a
bit. At 11 there’s still propwalk so I decided I preferred the power.
Unfortunately for reverse the only way you’ll
know what you prefer for sure is to try different settings. Forward is relatively
straightforward based on RPM.
Good luck and let me know how it works for
you.
Alan
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From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of Jerome Weinraub
Sent: Monday, February 20, 2006
7:57 AM
To: freedomyachts2003@yahoogroups.com
Subject: Re: [freedomyachts2003]
Max Prop
They set mine at 13" fwd,11 reverse-same engine and
gearbox. I bought a digital hand held tach,and I’m going to get accurate RPM
readings,as I don’t trust my tach.
I’ll make a fudge chart----- Original Message
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February
19, 2006 7:40 PM
Subject: RE:
[freedomyachts2003] Max Prop
\
I experimented a number of times and
currently happy with 12 pt pitch both forward and reverse. The forward appears
correct based on maximum RPM. The reverse is a matter of preference My slip
sometimes requires heading straight at it so I prefer more thrust in order to stop
although this gives more prop walk to port. If you prefer less fortunately the
Variprop allows separate reverse pitch adjustment. My transmission reduction is
2.61 forward and 3.16 reverse. Don’t know if yours is the same. Alan
Below is some general info from. Variprop
in case its helpful.
Re your numbered items:
(1) 1" of pitch = approx 200 engine RPM. So I would
start with 1-1/2" of pitch reduction and see what this produces in RPM
increase. I would target 3400RPM as the max. If you flatten the pitch to
get a sustained 3600RPM, your boat speed at a more reasonable crusing RPM will
be as lot slower, obviously.
(2) You can run continuously at any RPM that does not result
in (a) overheating and (b) black smoke. So if you throttle back to just maintain
say 2900 or 3000RPM, and if the engine is happy, no damage will result even
though the boat is theoretically “overpropped”.
The potential for damage begins when the throttle is opened
farther in an attempt to obtain more RPM. In this mode the engine is being
fed more fuel than it can efficiently burn, combustion efficiency is poor,
there is smoke, etc.
(3) To reduce propwalk: you can reduce the pitch in Reverse
by 1" or even 2". This will result in a decrease of thrust and
therefore of stopping power but I expect it will be a very satisfatory
tradeoff. Even with this adjustment, your VariProp will produce considerably
more reverse thrust than will a normal fixed prop.
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of Jerome Weinraub
Sent: Sunday, February 19, 2006
12:45 PM
To: freedomyachts2003@yahoogroups.com
Subject: Re: [freedomyachts2003]
Max Prop
Alan;
I have an F33(#68)And a new,and as yet,unused
Variprop,15.5".What settings did you change to?.I ordered mine as per your
suggestion.I’d like to see if your settings are what the factory set mine to
----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February
19, 2006 10:18 AM
Subject: RE:
[freedomyachts2003] Max Prop
\
I have an F-33 and found the Variprop has
a very short hub. They can provide 3 or even 4 bladed and it has a number of
other benefits. They also do custom sizes so the do 15.5” instead of 15
or 16 which are standard sizes (no real cost difference). I played with the pitch
a bit although their calculations were usable. If you mention F-33 to
Michael 804-436-0150 www.varipropusa.com fax 804-436-0140 and my name
he’ll be able to look up all the specifications on mine although your 32
would be a bit different)
I’ve been very happy with it and
have had it for several years.
Alan Kusinitz F-33 Hull #51 1982
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of andre laviolette
Sent: Sunday, February 19, 2006
9:30 AM
To: freedomyachts2003@yahoogroups.com
Subject: Re: [freedomyachts2003]
Max Prop
Bob,
\
If you can send me the reduction ratio stamped on the I.D.plate of your
reduction gear I may be able to help. It seems to me that the diameter of
your prop is much to small for the engine you have . In broad and general
terms, diameter is what gives you push and stopping power. Blade area is
capital here. Pitch gives speed. Send also h.p. and max RPM indicated on
engine i.d. plate. Weight of vessel and sailing water line length would nail it
down.
16 in. whether 2 or 3 blade is probably correct. Pitch would also vary vary
depending on what you send.
\
Andre.
\
Bob Frew
<rfrew@…> wrote:
Last year I looked at Autoprop and found out that I
did not have enough clearance. this year I called
Max
prop and they will sell me a 14" 3 blade for
2240.
They said that the 3gm was probeably not the
original
engine. was too much power for a 14 2 blade and
the 3
blade would work much better. Does anyone have an
opinion on this.
thanks, Bob Frew, Freespirit, Freedom 32.
Find your next car at Yahoo! Canada
Autos
Posted by Thomas Wales (twales@…>)
My 14" 2 blade works just fine with my Yanmar 3GM. I don’t believe there
would be enough return on the increased speed investment to purchase a
feathering prop. There is information available on the web comparing prop
sizes, drag, and propulsion between 2 bladed, 3 bladed, fixed and
feathering. You might want to do some research before you make the
investment in a folding or feathering prop. By the way, the Hoyt 32’s did
have the 3GM as original engines. The Mull 32’s did have the 2GM as
original equipment because the boat was lighter.
Tom Wales
Anoush Koon F32 #20
At 07:25 AM 2/18/2006 -0800, you wrote:
Last year I looked at Autoprop and found out that I
did not have enough clearance. this year I called Max
prop and they will sell me a 14" 3 blade for 2240.
They said that the 3gm was probeably not the original
engine. was too much power for a 14 2 blade and the 3
blade would work much better. Does anyone have an
opinion on this.thanks, Bob Frew, Freespirit, Freedom 32.
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Posted by Jerome Weinraub (zayde@…>)
My digital tach works by placing a reflective tape spot on the flywheel,and pointing the hand held at it . A laser beam is reflected from the spot,and voila -accurate measurement ,to .01%.Thanks for your input
Jerry
----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Monday, February 20, 2006 8:16 AM
Subject: RE: [freedomyachts2003] Max Prop
That’s what they calculated for mine originally. I sent them my eventual settings but guess they still use their calculated ones. I checked mine against RPM both on the engine tach but also with a mechanical tach (I can’t remember the proper name but you lay it on the engine and pull out a wire that vibrates and you adjust until the wire appears still and that’s the RPM on the dial, very inexpensive but works well, the digital should be great).
I think the 13 is too high for forward (but you can always hold back a little on the throttle so its not running at max, I don’t think 13 is way overpitched just slightly) but let me know what you find if it differs. The problem with going too high first is that if you power hard for long periods of time and the pitch is too high the engine may overheat.
The 11 in reverse is probably fine but it depends on thrust. At 12 mine stops on a dime but is pulling to port quite a bit. At 11 there’s still propwalk so I decided I preferred the power.
Unfortunately for reverse the only way you’ll know what you prefer for sure is to try different settings. Forward is relatively straightforward based on RPM.
Good luck and let me know how it works for you.
Alan
The information contained in this e-mail and any attachments is intended only for the personal and confidential use of the recipient(s) named above and may be subject to attorney client privilege if so marked. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail, and delete the original message.
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of Jerome WeinraubSent: Monday, February 20, 2006 7:57 AMTo: freedomyachts2003@yahoogroups.comSubject: Re: [freedomyachts2003] Max Prop
They set mine at 13" fwd,11 reverse-same engine and gearbox. I bought a digital hand held tach,and I’m going to get accurate RPM readings,as I don’t trust my tach.
I’ll make a fudge chart----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February 19, 2006 7:40 PM
Subject: RE: [freedomyachts2003] Max Prop
I experimented a number of times and currently happy with 12 pt pitch both forward and reverse. The forward appears correct based on maximum RPM. The reverse is a matter of preference My slip sometimes requires heading straight at it so I prefer more thrust in order to stop although this gives more prop walk to port. If you prefer less fortunately the Variprop allows separate reverse pitch adjustment. My transmission reduction is 2.61 forward and 3.16 reverse. Don’t know if yours is the same. Alan
Below is some general info from. Variprop in case its helpful.
Re your numbered items:
(1) 1" of pitch = approx 200 engine RPM. So I would start with 1-1/2" of pitch reduction and see what this produces in RPM increase. I would target 3400RPM as the max. If you flatten the pitch to get a sustained 3600RPM, your boat speed at a more reasonable crusing RPM will be as lot slower, obviously.
(2) You can run continuously at any RPM that does not result in (a) overheating and (b) black smoke. So if you throttle back to just maintain say 2900 or 3000RPM, and if the engine is happy, no damage will result even though the boat is theoretically “overpropped”.
The potential for damage begins when the throttle is opened farther in an attempt to obtain more RPM. In this mode the engine is being fed more fuel than it can efficiently burn, combustion efficiency is poor, there is smoke, etc.
(3) To reduce propwalk: you can reduce the pitch in Reverse by 1" or even 2". This will result in a decrease of thrust and therefore of stopping power but I expect it will be a very satisfatory tradeoff. Even with this adjustment, your VariProp will produce considerably more reverse thrust than will a normal fixed prop.
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of Jerome WeinraubSent: Sunday, February 19, 2006 12:45 PMTo: freedomyachts2003@yahoogroups.comSubject: Re: [freedomyachts2003] Max Prop
Alan;
I have an F33(#68)And a new,and as yet,unused Variprop,15.5".What settings did you change to?.I ordered mine as per your suggestion.I’d like to see if your settings are what the factory set mine to
----- Original Message -----
From: Alan Kusinitz
To: freedomyachts2003@yahoogroups.com
Sent: Sunday, February 19, 2006 10:18 AM
Subject: RE: [freedomyachts2003] Max Prop
I have an F-33 and found the Variprop has a very short hub. They can provide 3 or even 4 bladed and it has a number of other benefits. They also do custom sizes so the do 15.5” instead of 15 or 16 which are standard sizes (no real cost difference). I played with the pitch a bit although their calculations were usable. If you mention F-33 to Michael 804-436-0150 www.varipropusa.com fax 804-436-0140 and my name he’ll be able to look up all the specifications on mine although your 32 would be a bit different)
I’ve been very happy with it and have had it for several years.
Alan Kusinitz F-33 Hull #51 1982
From: freedomyachts2003@yahoogroups.com [mailto:freedomyachts2003@yahoogroups.com] On Behalf Of andre lavioletteSent: Sunday, February 19, 2006 9:30 AMTo: freedomyachts2003@yahoogroups.comSubject: Re: [freedomyachts2003] Max Prop
Bob,
If you can send me the reduction ratio stamped on the I.D.plate of your reduction gear I may be able to help. It seems to me that the diameter of your prop is much to small for the engine you have . In broad and general terms, diameter is what gives you push and stopping power. Blade area is capital here. Pitch gives speed. Send also h.p. and max RPM indicated on engine i.d. plate. Weight of vessel and sailing water line length would nail it down.16 in. whether 2 or 3 blade is probably correct. Pitch would also vary vary depending on what you send.
Andre.
Bob Frew <rfrew@…> wrote:
Last year I looked at Autoprop and found out that Idid not have enough clearance. this year I called Maxprop and they will sell me a 14" 3 blade for 2240.They said that the 3gm was probeably not the originalengine. was too much power for a 14 2 blade and the 3blade would work much better. Does anyone have anopinion on this.thanks, Bob Frew, Freespirit, Freedom 32.
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