T.R | Title | User | Personal Name | Date | Lines |
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497.1 | | GIAMEM::LAMPROS | Bill Lampros | Mon Aug 28 1989 17:17 | 11 |
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Gordie,
I don't have an answer but I have a 14' fiberglass runabout
with a 20HP Johnson. It pulls me up (195#) with some difficulty
but once up I ski at about 18-20 knots. I'm upgrading to a 35hp
Merc and hope better results.
My understanding, by the way, that besides horse power
and prop type, the right length shaft is very important.
Bill
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497.2 | A couple of suggestions | NRADM::WILSON | Southern NH, The Mass. Miracle | Mon Aug 28 1989 17:37 | 18 |
|
Gordie,
Two things to check:
Make sure the motor is trimmed all the way in, as close to the
boat's transom as you can get it. This will knock a few mph
off the top end, but make it much easier to get on plane. This
is where power trim really comes in handy.
And all passengers in the boat and moveable equipment should be
moved to the front of the boat. Once up on plane the passengers
can move toward the rear it it's more confortable there.
I agree that 40 hp on a 13' Whaler should be plenty to ski with.
I used to ski without too much trouble behind my old 14' fiber-
glass boat with a 1961 Evinrude 40.
Rick
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497.3 | Try a stabilizer | DONVAN::DECAROLIS | The Open has opened | Tue Aug 29 1989 09:33 | 13 |
| I would recommend a Doel-fin, stabilizer, whale-tail, etc.
I had one installed on my 35 HP Merc this summer, there's
a big difference in pick up and planing off... I like to
keep the motor tilted at "for speed", not for power. There's
too much of a noticeable difference at top speed.
If you don't think you'd miss a few miles off at top end,
a combination of having the motor tilted in with a stabilizer
would give much better pick-up and planing.
Jeanne
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497.4 | | PACKER::GIBSON | I'm the NRA | Tue Aug 29 1989 12:18 | 9 |
| It sounds like you have allready checked for the most likely things.
Prop pitch and motor tilt/trim. You may want to look at your spark
plug; if it's fouled you will have power loss at low rpm. also any carb
adjustment; it could be running to rich. maybe looking at your fuel/oil
mix to make sure it's 50:1 ? and also check your air filter.
With a 40 hp that boat should fly at a touch of the throttle!
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497.5 | 35HP should be enough on a light boat | ULTRA::BURGESS | | Wed Aug 30 1989 12:16 | 13 |
|
re .0 Three years ago we were playing with a wooden
"Cadilac" boat with a 35 HP Johnson motor, it pulled skiers up to 220
lbs without too much problem (no slalom deep water starts though). I
know it was a '58, I rebuilt it for the guy this year, so I needed
the model and serial numbers from it.
Reg
{Well, I suppose you COULD see what the Mastercraft dealer
would give YOU for trade in on a 13 ft Whaler (-: }
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497.6 | Boat/motor combo shold be adequate | BIZNIS::CADMUS | | Wed Aug 30 1989 12:50 | 31 |
|
Something's definetly wrong.
A 13' Whaler with a 40 HP should be able to pull a skier with no
sweat.
If the motor is runng OK( Not missing or sputtering),, then it could
be:
, Weight distribution ( you want the weight in front)
. Prop has too much pitch ( you seem to have eliminated this)
. Motor tilt too far back
I have a freind whio has a 13' whaler with a 25 HP merc- pulls teenage
water skiers( 2 skis) up to about 150-160# all the time. With a 40 that
baot should have plent of oomph.
I'll go along with the doel- fin type stabilizer. They really help in
getting up on plane.
Have the engine comp[ression and tinming checked. You could have
the timimng way off which can result in fryng the pistons.
It sound like you have eliminated the obvious external problems.
Just as a note- I weigh 220 (middle age is creeping up fast) and A
freind with a whaler type boat with an ancient 35c HP Chrysler got me
up on two skis easy. Something is definetly wrong.
D................
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497.7 | So I'm not nuts. | MAMIE::CORZINE | Gordie | Fri Sep 01 1989 14:31 | 22 |
| Thanks for the sanity check, everyone.
The shaft length is correct. I could trim it in, and may try it.
However, efforts to urge it to plane by getting the observer up
to the bow actually seemed to make it worse.
When it's trying to pull me out, the engine does tend to miss
occasionally. So, I think there is a real problem in the engine. Mind
you, it's fast at high revs--faster than I wanted to ski the one time I
did get up. I had the dealer do a lot of work on the rig before I put
it in the water, but a check of the bill revealed that he didn't touch
the engine. I doubt that the plugs were ever changed this year.
With school starting and cooler days, I've decided to let it go
for this year. Next year I'll have the dealer replace the plugs,
adjust the timing, check the compression and replace the air filter.
I feel confident the problem will be fixed (or at least identified).
At least I won't spend the next 8 or 9 months feeling like I've
made a stupid mistake.
Again, thanks to all of you who responded. Gordie
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497.8 | Driver's check your engines! | OFFPLS::LOWNIE | | Wed Sep 06 1989 13:27 | 26 |
| Old note....new input
Just adding this so you'll know there's hope......
Went out with my usual group to Ski the Merrimack last week. We use a
Sutphen with a 200 Merc (Screamer.....70+ mph).
We had a bit of trouble starting it, but finally got it going. I jumped
in to take the first run. I use a radical slalom ski (Kidder Redline
which takes "a bit" to get up on) and I have double boots so I have to
start with both feet in. Well, this particular time I got dragged, and
dragged, and then dragged some more. And this from a boat that normally
can pull 3-4 SLALOM skis out at the same time (We actually did four
last summer!). Once up, everything was great, but each time someone
'started' it was hell.
Owner took the boat into Marina for a look see......problem was a bit
of dirt in the carbs. That's it.....just a bit of gunk and our
marvelous, powerful monster was reduced to the pull of a kayak with a
broken paddle.
Have your engine checked and I imagine you'll be very impressed!
BJ
p.s. For the fun of it I did a flying dock start behind a 12' grady
white with a 25hp Evinrude at Winnisquam last weekend........and it worked!
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497.9 | A solution--finally | WOODRO::CORZINE | Gordie | Fri Sep 07 1990 17:23 | 20 |
| Time to update this discussion.
I had a local wizard go over the engine thoroughly this Spring. Guess
what, he couldn't find anything wrong. He tested the boat in water and
all.
He suggested the doel- fin stabilizer. That did the trick. Not only
does it now pull skiers as it should, general handling is much
improved--smoother acceleration and finer control at moderate cruising
speeds. The boat used to have only too speeds--too fast (back-crushing
pounding on the seas) and too slow.
My theory is that the Whaler tri-hull has excessive wetted-surface drag
until it begins to plane. The stabilizer seems to reduce cavitation
for greater thrust at low speeds when all that hull surface is dragging
through the water. Bottom paint (I use an anti-fouling paint) and
other esoteric factors may account for differences from one rig to
another.
Anyway, this boat has earned a new lease on life.
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