Author Topic: 67 V172 20mph??  (Read 14911 times)

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Offline Rosscoe

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Re: 67 V172 20mph??
« Reply #20 on: October 02, 2010, 06:48:13 PM »
A razor?
Ross
61 Surflite 1964 90HP Johnson project
67 V163 Bayflite Super Sport  1989 100HP Merc
67 V164 Bayflite 120HP
67 V174 Crestflite Rat Rod
71 V175 Crestflite 350ci -Jet
73 GT 160
84 CVX 17  83 115 Merc
88 CVX-23 350 Mag

Offline David CVX-16

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Re: 67 V172 20mph??
« Reply #21 on: October 03, 2010, 12:46:31 PM »
Advertisement on Craigslist for boat hull powerwashing and cleaning:

http://minneapolis.craigslist.org/hnp/boa/1986432141.html
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop

74 Carlson

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Re: 67 V172 20mph??
« Reply #22 on: October 03, 2010, 08:44:37 PM »
Muratic acid it can be purchesed at most hardware stores and use as straight, You will need a gallon. Buy a throw away sprayer and go to the car wash unless you have a pressure washer. Blue Lagoon marine at the time I worked there we went threw 300 boat bottom cleanings, they bought muratic acid by the 55 gallon drum. Wear protective clothing you dont care about rubber gloves, eye goggles, long sleeve shirt. Thats what happens after years of sitting in the lake every summer with out yearly cleanings. Make sure the boat bottom is dry and use the acid straight! If you have a galvanized trailer it may discolor the only help to prevent that is water down the trailer and carpeted bunks. Spray on the muratic acid heavy and let sit for 5 min and then pressure wash. Also a face mask is a good idea, dont breath that stuff!

Offline Jason

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Re: 67 V172 20mph??
« Reply #23 on: October 03, 2010, 10:40:09 PM »
Thanks Steve! I will try that. I am just not to sure what people will think when I walk into the car wash with a rubber suit, gloves, and big goggles!

If i find a pressure washer, and try this in the driveway, do you think it will eat asphalt?
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline Jerry

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Re: 67 V172 20mph??
« Reply #24 on: October 04, 2010, 12:47:22 AM »
You can use my power washer if you want Jason.
Call me If you have the list

I also have some H2SO4
'72 Glastron GT160 Sport - Okie-Dokie
'63 Winner - Grandpa's Fisn-Bote
'63 Glasspar SeaFair Sunliner - Mischief Maker

Offline Hotwired

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Re: 67 V172 20mph??
« Reply #25 on: October 04, 2010, 12:24:27 PM »
Thanks Steve! I will try that. I am just not to sure what people will think when I walk into the car wash with a rubber suit, gloves, and big goggles!

If i find a pressure washer, and try this in the driveway, do you think it will eat asphalt?

Muriatic acid will definitely raise heck with asphalt and will really brighten up your concrete! Go have lunch at a lake near Jerry (soak the boat for an hour or more) and then give the pressure washer a try or take it to the car wash and hit it with the acid.  We used to pressure wash boat lifts in the fall after taking them out of the lake for the summer.  Most of the nasty stuff just sprayed off with the power washer or even with a high pressure hose nozzle ... one of those 1/8" opening things you can get from a hardware store.
.. it is what it is ... and that is how it should be!
Miss Mayberry - 1964 Saberflite
The Ship - 1979 CV-27
Canon Ball Eyes - 1976 CV-16ssV8
Da ProJect Bote - 1977 CV-23
It Is What It Is...... CVX20

Offline Jason

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Re: 67 V172 20mph??
« Reply #26 on: October 04, 2010, 02:11:13 PM »
I think I am gonna try the car wash first. Maybe I'll spray it on in a walleyworld parking lot (take that wally). Then hit the car wash. Just not sure How I am gonna get under the bunks. May have to make a second trip with the boat on the trailer a little crooked.
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline Hotwired

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Re: 67 V172 20mph??
« Reply #27 on: October 04, 2010, 02:19:41 PM »
When I was working on my Saberflite bottom I put 2x spacers above the bunks perpendicular to the bunks.  I used pieces about a foot long to make a space above the bunks.  Space the 2x's about two feet apart.
.. it is what it is ... and that is how it should be!
Miss Mayberry - 1964 Saberflite
The Ship - 1979 CV-27
Canon Ball Eyes - 1976 CV-16ssV8
Da ProJect Bote - 1977 CV-23
It Is What It Is...... CVX20

Offline Jason

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Re: 67 V172 20mph??
« Reply #28 on: October 04, 2010, 10:52:12 PM »
Got some Muriatic acid after work today. Backed the boat up to the woods, sprayed a bunch of acid on it, drove down to the car wash, and it just peeled right off. I am hoping to get in a test run tomorrow assuming I can find a ramp that isn't flooded!
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

74 Carlson

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Re: 67 V172 20mph??
« Reply #29 on: October 05, 2010, 05:46:52 PM »
Muratic acid also works great as a weed killer, also used to adjust ph balance in hot tubs and swimming pools.

Offline Jason

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Re: 67 V172 20mph??
« Reply #30 on: October 05, 2010, 07:31:25 PM »
Got in a test run on Lake Mallalieu in Hudson today.

34mph (boat speedo) but only getting about 4100RPMs. I am happy with the speed as it's what i expect but seems like the RPM's should be higher.
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline Hotwired

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Re: 67 V172 20mph??
« Reply #31 on: October 05, 2010, 07:40:13 PM »
150% of the first test!  Sounds like you might need to re-prop!
.. it is what it is ... and that is how it should be!
Miss Mayberry - 1964 Saberflite
The Ship - 1979 CV-27
Canon Ball Eyes - 1976 CV-16ssV8
Da ProJect Bote - 1977 CV-23
It Is What It Is...... CVX20

Offline Rosscoe

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Re: 67 V172 20mph??
« Reply #32 on: October 05, 2010, 07:43:14 PM »
Taking the fur off really helped!
You are already running a 17, right? I wouldnt think you'd want smaller then that, would you? More rpms, but less speed? David....!
Ross
61 Surflite 1964 90HP Johnson project
67 V163 Bayflite Super Sport  1989 100HP Merc
67 V164 Bayflite 120HP
67 V174 Crestflite Rat Rod
71 V175 Crestflite 350ci -Jet
73 GT 160
84 CVX 17  83 115 Merc
88 CVX-23 350 Mag

Offline David CVX-16

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Re: 67 V172 20mph??
« Reply #33 on: October 05, 2010, 08:27:58 PM »
The RPMs do not seem right at 34 MPH with a 17" prop.  Also, 40 MPH should be attainable. The motor at full throttle should be running around 5,300 RPM, and to get there from 4,100, a difference of 1,200 RPM translates to 6" down in pitch. I would test the tachometer and speedometer for accuracy and then check the prop. What is the make and model? What is the diameter of the prop? It should be around 13". If larger in diameter, it would account for the drop in RPM. Has the prop been reworked? Did you mention the make and model of the prop? Off brand props can be much slower than the Mercury Quicksilver, which are designed by the engineers for the torque and horse power curve of the in-line six. A good bench mark prop would be the basic aluminum Mercury Quicksilver three blade prop in 17" pitch. They are common and a used one might be $75. Something does not seem right currently.  
« Last Edit: October 05, 2010, 08:30:20 PM by David »
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop

Offline Jason

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Re: 67 V172 20mph??
« Reply #34 on: October 05, 2010, 08:38:41 PM »
I have not checked the Tach for accuracy yet. I hope it's accurate because when I rev it in neutral it will go up to 6000. Don't worry, it was just a quick rev!

I know it's a Mercury brand prop and it looks like a 13" to me. It's for sure a 17P too. I'll have to get the part number off of it sometime. It looks fairly new.

I am curious what a 15P would do.

I know the boat seems big but it's under 800lbs not including the engine. Overall, it's lighter then my CV16SS at 1200 lbs with the I/O. Just seems like the 17 is the right prop for this boat.

hmmmmm.
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline Jason

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Re: 67 V172 20mph??
« Reply #35 on: October 05, 2010, 08:40:15 PM »
oh, it has a hydrofoil on it too. Not sure if this would affect things or not.
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline David CVX-16

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Re: 67 V172 20mph??
« Reply #36 on: October 05, 2010, 09:22:29 PM »
The prop part number should end in a dash and then a two digit number, which is the pitch of the blades.  Post the part number and we can determine the rest from charts.
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop

74 Carlson

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Re: 67 V172 20mph??
« Reply #37 on: October 10, 2010, 06:54:29 PM »
Those hydrofoils are designed to help under powered boats with crappy hull design's. In my opinion they have no place for the lighter hulls with good power. Just think if those hydrofoils helped so much the factory would have made them part of the cavatation plate as one peice.

74 Carlson

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Re: 67 V172 20mph??
« Reply #38 on: October 10, 2010, 07:00:42 PM »
Like David said make sure the tach is dialed in befor ya start swapping props. I would remove the hydrofoil and lake test again to see if there is a differance which I think there will be for the better.

Offline David CVX-16

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Re: 67 V172 20mph??
« Reply #39 on: October 10, 2010, 09:27:27 PM »
Jason, with the hull sitting in the water for so long with algae building up, wondering if you have extra weight from water under the floor. It seems like the 95 HP Merc with a 17" prop on a 17' boat should go in the low 40 miles per hour turning 5,000 RPM.
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop