Conference vicki::boats

re            <<< Note 1146.0 by GLDOA::DBOSAK "The Street Peddler" >>>
>                  -< Transmission Ratio/H/P/Prop Selection? >-
    
>    Soooo, they put in 2:1.  Now, I get about 3300-3500 RPMS.

	Check with the supplier of the engine - I mean the 
"marinizer", not a generic mechanic.  According to what cams they have 
the WOT RPM is likely to be somewhere in the 4,000 - 4,500 range.

	If that is the case and you want to let them rev up there the 
choices are probably  a) get the props re-pitched  b) get the 
transmission gears changed.   My guess is that re-pitching the props 
would be the lower cost alternative.

	Reg

    ...especially if you only buy one pair of props.  You could still use
    the older props as spares...
    
    Carl

        Thanks -- Based on your suggestions, I called Crusader engine to
        ask about the issue --
        
        Interesting comments -- If you are at WOT and aren't between 4000
        and 4500 RPM, you are lugging down the engine and it will burn out
        sooner.
        
        The general rule of thumb is:  Change Pitch or Diameter by 1 inch
        to change the WOT RPM by 150-200.
        
        For me, at 3500 RPM, I'm supposed to change the combination of Pitch
        and Diameter by 5 inches downward.
        
        Crusader said that Michigan Wheel has a computer program that will
        analyze the boat parameters and recommend a proper prop.  They are
        FAXING the data sheet for me to fill out -- I'll put it in here
        when I get it and will also put in their analysis of the Queen's
        situation.
    
    If you want to contact Michigan Wheel Directly for your interest --
    (616) 452-6941 --- Ask for the Sales Department.
    
    Regards,
    
    
    Dennis
    

    
    	You may have to change the gear ratio of the tranny's and repitch
    	the props as well.  Changing the prop's pitch by one inch will only
    	add approximately 100 to 200 rpm's.  In your case if you were only
    	repitch your prop's you will have to decrease the pitch 5 to 10
    	inches.  What you really need to do is have a custom boat builder
    	who knows what he is doing determine what you gear ratio should be
    	along with the diameter and pitch of your props.  Having the right
    	set-up will not decrease your milage but will probably add
    	considerably to you speed and efficiency.
    
    	George
    

    I just talked to my prop guy who does the work on my props -- He said
    that I can pick up 400 RPM by cutting down the props by one inch and
    then get another 400 rpms by decreasing pitch by 2 degrees.
    
    Still waiting for the Michigan Wheel FAX.
    
    The reduction gear (new) is about $700.00.  There may be some used ones
    around.  My Marine Mechanix is checking into that.
    
    Dennnis

re             <<< Note 1146.5 by GLDOA::DBOSAK "The Street Peddler" >>>
>                                -< S'more Info >-
    
>    The reduction gear (new) is about $700.00.  There may be some used ones
>    around.  My Marine Mechanix is checking into that.

	right,    and don't forget  "labor"
    
>    Dennnis


	BTW, there are also practical limits to how small of a prop
diameter you could use - similarly how low the pitch could be made and 
still leave you with a useful prop.  I think small diameter low pitch 
props on heavy boats give some serious problems at low speeds - ??   
My original guess was based on an assumption that you could have the
props re-pitched and/or blades trimmed the next time they go in for
rebuild/repair, get the other two done the next season, etc.  Anyway, 
a call to H&H would probably help you understand whether its practical 
to have them changed that radically.

	Reg

    I was going to refer Dennis to H + H (props) and Marine Gear (Warner
    Drives) until I found out he was from Detroit, Michigan, and they must
    have local sources out there.  I would bet the "Michigan Wheel" prop 
    factory is close by and I believe Warner (assuming you have Warner
    reduction gears) is also close by.
    
    By the way, $700 for new Warner reduction gears (there goes that
    assumption again) is an excellent price seeing that I was quoted $1200
    for a new 1:1 ratio unit and what you need is basically the 1:1 unit
    with added gearing hanging off the tail end.  Are you sure of that
    price?  I was talked into finding a used unit and having it rebuilt by
    the local Warner Drive Dealer (Marine Gear).  The cases don't go bad
    nor do alot of the internals.  I ended up with a rebuilt unit with a
    year warranty for $400.  That included heavier duty clutch springs for
    waterskiing.  We have a local weekly advertising magazine called "Want 
    Advertiser" that always has different reduction gears in there at good
    prices.  I also know that Marine Gear (Rowley, Mass.) has a bunch of
    used reduction gears (not just Warner) that he buys or takes in trade
    to rebuild for sale.  You might have a local place that would do that.
    Wayne

    Re: .7
    
    Thanks -- With the boat show coming up in a couple of weeks, I'll nose
    around.
    
    My mechanix is coming over to my house tonight -- I'll see what he
    says.
    
    Dennis

    i would ask what would happen when your backing down.
    
    how much control would be lost with a smaller prop.
    
    
    i agree in some sense, but why are you trying to increase
    rpm.
    
    JIm

    Jim:
    
    It started when I read an article on re-powering in a boat magazine --
    A 454 CID is supposed to turn 4250 RPMs at WOT.
    
    I ended up checking with Crusader on WOT vs RPM for my engines -- They
    said that at WOT the RPMs should be between 4000 and 4500 RPM -- At my
    WOT RPM of 3400-3500 the expert said I'd burn a piston.  I'd also burn
    out the engines much sooner than predicted life cycle.
    
    He said I also use lots of fuel I don't need to use.
    
    In the process of getting everything right, I'll pick up around 10 MPH.
    
    I checked my props last night when I checked the Queen's cover (It's
    still on!)  -- I have 19 inch props with a 19 pitch.
    
    If my Prop guy is right, I'll end up with 18 inch props and a 17 pitch.
    
    Regarding boat handling -- The configuration now muscles the Queen
    smartly.
    
    At idle on both engines my forward speed is about 5-6 miles/hour.
    
    My guess is that I'll probably have to use more power at lower speeds
    and when docking/getting underway.
    
    Actually, I'm more concerned about docking -- That's when a body has a
    tendency to look really stupid to even the most casual observer!
    
    Dennis
    

    when docking, the goal for me is to set the throttles, and play
    
    with the clutches. Except in the slip i had last year. it took
    
    on average in 15 knot winds at least 4 people to dockit.
    
    1 at the helm, 1 in the cockpit, 1 on the dock, 1 in the boat
    
    next to me.  total = 4  more is better.  why, i had no pole
    
    to turn on, with a bridge and little keel, it anchors to the 
    
    starboard. talk about a little throttle.  this year i will
    
    have a pole, i negotiated it witht the marina, they agreed.
    
    
    i guess my concern is if you will need more throttle its okay
    
    when the wind is in favor or calmer, but when it blows, i'd
    
    be concerned about the "bite" it may not have.
    
    on the wot concern, my understanding is that cruising should
    
    be between 70-75% of wot, in this case about 3200, in your case 
    
    your there.  if i recall the Queen is in the 40' range, i would 
    
    think a larger wheel could be turned.  course there's that hole
    
    in the water theory $$$$$$$$$.
    
    i turn an 18x18 wheel, i can hit wot which is 4000 rpm, i cruise
    
    at 2800-3000.  on occasion i bring them up slowly to 4k for about
    
    3 min,  feels like your flying.
    
    JIm

    Jim:
    
    My 3400-3500 is WOT -- I agree, I'll cruise in the 3K range -- 
    
    Tell me about this pole U refer to.  I have a 40 foot ragbote next 2 me
    with a long boom(?) off of the stern mast -- In a strong wind, I have
    impaled the queen on it-- Blows me off of the dock kaddywampus
    (nautical term) and I end up sticking her 'bout 3/4 back.  
    
    The Fleet Admiral manages the bow -- What I would like to do is somehow
    snag something on the dock from the bow that lets me create a spring
    line -- That way I can keep the Queen's stern parts off of my
    neighbor's stick.
    
    The QUeen has a high freeboard -- About 6-7 ft -- The docks are
    floating docks -- Last summer I snapped the 4/4 at the end of the dock
    when I tried to twist the Queen into the slip (Starboard side to).
    
    This pole you refer to -- could this be one stuck in the bottom at the
    end of the dock?  
    
    Regards,
    
    
    Dennis

    
    i'm a louzy drawer in edt, but here goes.
    
    
    |     O        |  <------- finger pier
    |              |
    | B       B    |   boats are on either side of the "O" in this case
    | O       O    |   this is a pole sunk into the sea bottom. my slip
    | A       A    |   on the left side.   I dont have a pole, so in a blow
    | T       T    |   i have nothing to pivot on.  so the stern is free to
    |              |   move to the right in this diagram, into my neighbors
    |              |   boat
     _____________________________________________________
    
                   main dock (floating)
    
    ______________________________________________________
    
    
    
Marinas have different arrangements, but the pole gives you a pivot 
point for the stern when backing into the slip, once your in
it holds the bow or privents it from hitting you neighbor.
    
    
    
  the best approach is difficult to explain but i'll try.
    
                                       wind from southwest.
 bow of boat>  \
                \
                 \ 
   ------>approach\
    S              \              N
                    \
    
my approach is from the south, with a predominant sw wind. best thing is to
turn the bow to port and then back in, by the time the wind grabs the
bow your better than half way into the slip.   if you just line up
the stern with the slip, and thn back in the wind will have gotten
your bow and your at an angle to the slip and can't back in.
    
    
    
      JIm
    
    
    
    
    
    
    
    
    

    
    Jim:
    
    Thanks -- I guess I should consider backing into the slip in a high
    wind -- -- My slip is in the same orientation as yours -- With the pole
    in that location you show, I can do a port bow spring from the pole
     (Wind blows from the Stbd side) -- The Fleet Admiral can check the 
    line as I go into the slip -- It sounds like the Queen 
    ain't gonna get stuck by my neighbor's pole!  
    
    Good idea!
    
    Dennis

    
    	For the conclusion to the Throttle/Prop mystery of the Scurvy
    Queen, See note number 254.37 - Prop selection.