Author Topic: Anyone installed a set-back bracket or jackplate on a CVX16?  (Read 11669 times)

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Offline Plugcheck

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #20 on: September 26, 2018, 02:55:59 PM »
       Doug runs the jack plates solely to save the Manatees.   Even if it saves just one, its worth the money.   Just ask him.   
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline V153

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #21 on: September 26, 2018, 03:02:20 PM »
       Doug runs the jack plates solely to save the Manatees.   Even if it saves just one, its worth the money.   Just ask him.
Love em so much I just made another donation. $230 bucks. (Second offense ...)
'81 C500_given away, bought back_75.1 mph
'81 Baja 15SS_140 Frankenrude_66.7 mph
'70 something SpeedCraft_(Allison 16R Clone)_69.0 mph
'79 CVZ19_given away
'71 V153_54.8 mph_wrecked


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Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #22 on: September 26, 2018, 04:58:01 PM »
" Fwiw if your primary use is for pulling skiers/toys? I'd think you'd want the motor on the transom, prop buried deep. Imo. "

That's my thinking …
It's not a heavy boat and has a pad, thinking more LU in the water the better.
Maybe ...

Offline V153

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #23 on: September 26, 2018, 06:38:20 PM »
Well what it all boils down to is do ya wanna tow chit, or go fast. Try as you might, there is no happy medium.
'81 C500_given away, bought back_75.1 mph
'81 Baja 15SS_140 Frankenrude_66.7 mph
'70 something SpeedCraft_(Allison 16R Clone)_69.0 mph
'79 CVZ19_given away
'71 V153_54.8 mph_wrecked


WALK TALL AND CARRY A BIG BILGE PUMP

Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #24 on: September 26, 2018, 06:48:57 PM »
You can get a few more MPH out of it by changing props.
There's a guy on FB that picked up 10 MPH by going up from a 21P to a 22P prop …  :o

Offline Mechanick

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #25 on: September 26, 2018, 10:10:00 PM »
Great looking set up and color!  Thanks for the clarification.

Offline Mechanick

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #26 on: September 27, 2018, 12:36:11 PM »
Fwiw if your primary use is for pulling skiers/toys? I'd think you'd want the motor on the transom, prop buried deep. Imo.

Agreed—-the idea was greater stability from the setback of a jackplate, not really speed from tweaking the motor up with the jackplate. 

Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #27 on: September 27, 2018, 01:24:49 PM »
When you say "stability" .. Do you mean ability to track straight when a skier is cutting across and pulling on boat from an angle ?
CVX16's have pad's so there's not as much hull in the water as say a V hull, there designed more for speed then pulling skiers.
There also fairly light at 700 lbs. for just the boat, so under 1500 lbs. with you and fuel, battery, etc.

Repair hull and mount motor .. See how well it works ..
You can always add the jack plate later, bolt hole are the same as your motor, although your steering set up might have to be modified.
I would think a 150 HP motor and the right prop should work OK.

Offline Mechanick

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #28 on: September 27, 2018, 01:37:29 PM »
Thanks—good point I can add a jackplate later—I can still beef up my transom/knees to handle either way on the rebuild.  Wanted to figure out early if I had to make other mods now (eg steering) in prep for a setback.  But clearly my 18” setback idea is OUT...so thank you to everyone for the input.  Ha ha...I would have hated to have shown up at the next summer CGOAMN get together with an 18” setback to the derision of all ;). (Im betting my 6” jackplate will slide thru unnoticed.)

Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #29 on: September 27, 2018, 01:55:38 PM »
Yep .. Beef up transom no matter what you decided to do !
I went from G/C design of two, half inch boards nailed together .. to two three quarter inch boards with 1808 FG sandwiched between them. CVX design already has knee's but you could "beef" them up also.
Or even go with the poured composite transom.

Something to think about now is what are you going to use for a steering system ?
If you go NFB, your going to have to make some adjustments for cable routing if you get a JP.
Your with in HP limits of a Baystar, which would make set up and changes to set up much easier ..


Offline carlsoncvx18

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #30 on: September 27, 2018, 04:47:44 PM »
Have not had to much experience with a jack plate.  A good fried of mine had a fixed jack plate on a GT 150. Approx 6 in set back and height was fine tuned until it was just right.  Was not involved with the tuning process just was able to drive it a few times. Motor was a Yamaha 90.  It would go 55mph with no experience of chine walk. Very stable at that speed.   Out of the hole it was full trim down hit the hammer and hold up trim until it quit and you were gone. 

When doing something like that hydraulic steering would be the way to go because with a cable steer you would have to come out the back of the boat to make a nice radius of the steering cable.  That's what he did. 
1987 CVX18.     1968 Glastron alpha sail boat
1977 GT150
1986 CV23
1984 Intimiadator
1981 CV27
1969 V-180 fundeck

Offline David CVX-16

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #31 on: September 28, 2018, 06:55:44 AM »
Tom, from the Twin Cities, whom I have met twice on the rivers, has a CVX16 with a 115 HP with jackplate used for top speed in which he tries to elevate the motor as high as possible off the transom. Runs 22" and 24" Laser II props hitting about 60 mph. I would think that a jackplate is for higher top speeds, adding stability by positioning the motor further from the boat, acting as leverage
« Last Edit: September 28, 2018, 11:43:09 AM by David CVX-16 »
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop

Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #32 on: September 28, 2018, 11:01:54 AM »
I think it was Jerry that once commented that a JP would place the motor deeper in the water from the boats running surface compared to a motor on transom. Of course the JP would have more range of adjustment, to lift higher.
Like everything to do with set up, Ya never know how well it will work until ya try it …

Wondering about "Your" history of your CVX ?
Have you run it yet with the motor you have ?
What year is your motor ?

There's a "Fudge Factor" with boats and motors, a dealer can install a motor that's 15 % larger then rated cap. of Mfg.
But your 150 HP couldn't have been installed by a dealer, so must have been mounted at a later date.
Motor Mfg. also use the "Fudge Factor" on motors, Evinrude makes a 115 HP motor and a 115 HO  motor, which would have about 15 % more HP then the regular motor. Merc also makes a XS with higher HP then there regular motor.
Your Johnson GT150 would be one of the higher HP motors, maybe closer to a 175 HP motor, if it's in good shape and running well.

I would guess even with your motor on transom and a prop that would pull skiers .. You would still be able to get mid 50's MPH / GPS.

Offline V153

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #33 on: September 28, 2018, 03:58:37 PM »


I would guess even with your motor on transom and a prop that would pull skiers .. You would still be able to get mid 50's MPH / GPS.
I'd think it'd run a lil better'n that.
'81 C500_given away, bought back_75.1 mph
'81 Baja 15SS_140 Frankenrude_66.7 mph
'70 something SpeedCraft_(Allison 16R Clone)_69.0 mph
'79 CVZ19_given away
'71 V153_54.8 mph_wrecked


WALK TALL AND CARRY A BIG BILGE PUMP

Offline V153

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #34 on: September 28, 2018, 04:06:50 PM »
To put it into perspective. Once yer goin fast? It takes alotta HP to make ya go a whole lot faster.

If'n yer just gonna drag chit? That's a different story.
'81 C500_given away, bought back_75.1 mph
'81 Baja 15SS_140 Frankenrude_66.7 mph
'70 something SpeedCraft_(Allison 16R Clone)_69.0 mph
'79 CVZ19_given away
'71 V153_54.8 mph_wrecked


WALK TALL AND CARRY A BIG BILGE PUMP

Offline Mechanick

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #35 on: January 24, 2020, 12:39:29 PM »
Just to follow up and close this one out:   So I went with the general advice and just direct mounted the motor—a GT 150.   Without a jack plate to adjust I mounted it high (cav plate about 1” below trailing edge) and result was it constantly cavitated.  So before trying any adjustments I added a $60 ‘whale tail’ to see if i could keep it high without cavitating—that did it.  The 150 is an old motor (just over 100lb compression on all cyl) but she just flies now with superb handling (my first Carlson).  Snaps out of the whole too with tons of acceleration.  Next motor will be a newer 125/135 but as long as the old Johnson keeps running I’ll keep it on the boat.  Thanks to all for advice!

Offline Mechanick

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #36 on: January 24, 2020, 12:46:39 PM »
One thing to add: when rebuilding the keel and floor I switched the transverse 12(?) gal gas tank to a 20 gal and mounted it inline (with the keel) and as far forward into the nose as possible—so I’m assuming that might also be a factor in why the boat pops up so flat out of the hole. 

Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #37 on: January 25, 2020, 12:26:19 PM »
Should have been a 20 gal. tank, unless someone replaced it.
Crappy picture .. but it sat front to back originally.

Any pictures of boat and rebuild ?
We love pictures !

Offline Mechanick

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #38 on: January 25, 2020, 07:12:48 PM »
You bet....
2 pics of tank before/after.  You’re pic looks like the same tank as my original...that’s a 20 gal?!  Will take your word for it—maybe memory is poor on that one—I know the new one is 25 spun 90 degrees...more centered and further forward.

2 pics of rebuilt keel, transom and floor using Koosa board... but had purchased 3/8” thick for flooring—too flexible even for that narrow span so added in cross-members—worked out well.

2 pics of new seating—went with deep bench to make it super comfy and got a bit (too?) carried away with a 70’s “stars and stripes” seat covering (...I blame my dear old mum who helped me plan the sewing bit—we laughed thru the whole thing—priceless memory)...

1 pic of finished boat....man does it MOVE!  I grew up with speedboats...this one is a beauty for handling and speed —takes a turn like a race-car ;)

Offline Hyperacme

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Re: Anyone installed a set-back bracket or jackplate on a CVX16?
« Reply #39 on: January 25, 2020, 07:33:40 PM »
OK .. I'm sorry it would have been a 18 gal. tank ..
Maybe early CVX's had tanks mounted like late CV16's.
Any CVX16 owner know ?

Picture is my tank (18 gal.) in CV16.

Your CVX looks GREAT !