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Discussion Starter · #1 ·
I have a 71 hondo flat, I have had the boat for 7-8 years and have used it that many times as well . It was a project that when finished it ran but was never dialed in to the point that I felt confident to run it out. It has a blown 427 chevy for power. The v drive unit was rebuilt by Cassell and the prop was new by Kinsvater. I have lost the paper work to the v drive so I dont know what gears are in it . All the specs were given to Cassel and they came up with the gears to install. The prop is a 11 1/8 x 16 new and never trimmed.
Basically what happens is this, with the plates flat the boat accelerates well but when the power and rpm come up the boat responds by leap frogging so to control this it requires more down peddle and with the plates up ,"well you guys already know the answer there".
What I would like to do is get the plates to a starting base line so everybody is all on the same page and go from there.From what I have read engine placement and drive placement is important so I took photos just to get us started.
Any photos you might want to see I will be glad to take and if anybody knows how to tell what gears are in the drive let me know and I will get the info.

Its hard to see but the drive unit is 87" and the motor plate is 30" both from the inside of the transom.

Man I should have washed it befor pics. Thats Mendota slough goo for ya.












 

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First of al, what RPM's are you running when the boat starts to porpoise ??? Start with a straight edge, measure 3 feet from where the plate ends under the boat toward the front to every turn buckle and adjust each one to the straight edge, go through them about 4 times bechause every thing will change as you adjust them. Also make sure you have at least 2 stiff springs to pull the pedal up, when you get going the water will suck the plate down and it will kind of flap with not enough spring pressure. When you get all the turn buckles even, take all of them and crank them down 1/2 turn with the exception of the rt outer, take that one down a full turn, the 2nd and 3rd one in take 3/4 and 5/8 th's. on the left side the outer only 1/4 turn down. I'm thinking a 16 pitch with your set up and 15 or 18 gears will have a bit of a torque pull problem to the left at wot. Ideally you should have about an 11 1/4 15 with about 22 or 25 gears for a good river racer. More gear and less prop will decrease torque, drive the nose up and give you more control. When you get it close, 1/4 of a turn here and there will Really make a difference........... Ideally when you are cruising ablut 40 to 50 mph, the boat should pull to the right, when you nail it at that speed it should just fly out of the water and come down and set, and you should just about be able to take your hands off the wheel at wot with no torque pull..............When you finally get it set up in the neutral position of the down pedal on the trailer, push the pedal down 1/2 in and put a safety collar stop on the rod so it cant go up to far. You can fine tune the collar after every ride. Then when you punch it from a dead, it should just dig a hole in the water and set, and all you have to do is feather the down to make and keep it set. Then you DEFINATELY need a kill switch, jacket and a whirl a way .................. It never ends !!!!!!!!!!!!:D
 

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Measure from the end of the strut barrel to the end of the cav plate.

That prop is just a little too close to the strut for blown power. You might find the prop will touch the strut under power. Better space it back a nickle or 2.
 

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I was wondering how you get the prop puller on that deal... (without pulling the shaft back)...

Steve
I was thinking the same thing. And if you never pull the prop off, you might want to thing about getting it mag'd to check for cracks
 

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Discussion Starter · #6 ·
Ok Fiat from the end of the strut barrel to the end of the plates I come up with 25 1/2 to 26 inches depending on how its measured.

Violater, I will set up the plates as you recommended with some pics. later tonight

As far as the clearance between the prop and strut I had shortened it by at least 1/2" to what you see there knowing it can be shimmed back.

What would you guys like to see as far as clearances between prop and strut? 1/8 ,3/16,1/4? at this point I am flexible.
 

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Personally, I would set it where you could get your prop puller in between the prop and the strut barrel... That is all you need...

Steve
 

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OK that is a "normal" strut location.
Since this is a flat and not a runner......and the motor location and V drive location is further back than any runner I have ever seen...I am hestitant on making suggestions.

The plate is an extention of the boat so you certainly need the plate at least flat with the bottom of the boat in my opinion.

11 1/8 x 16 Kindsvater prop bites pretty hard. I'd venture to guess a 22 gear and not over. Not any big deal to pull the cover and find out what gears you have.

The motor seems too far back to me but I'd listen to someone with more experience with a true flat than I have make suggestions before changing any locations.

PS: The reason I asked for strut location was that you never know where these boats have been and what changes have gone on....right or wrong. If the strut was way under the boat then that could have caused problems. But this one is ok.
 

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Discussion Starter · #9 ·
Ok I have depressed the down pedal and inserted one shim thinking that would be the middle of the pedal movement. Then adjusted the plates as instructed by Violater and this is what it looks like


with a straight edge laid across from side to side there is a shallow v shape towards the middle and then basically flattening out in the middle between the two center rods. The depth of the v is a strong 5/16" {on a side note, after adding the additional turns of the adjusting rods there was very little change to the overall shape of the plate}

So how am I looking? am I OK so far?

I called Casale and talked with a person down there and as I figured just to much time has passed ,he could not find any paper trail on the rebuild. I asked if there is any way to know what gears are installed and the short answer was to split the case. He said I could guestimate by by marking the two shafts and eyeballing a percentage.


So I came up with this brilliant idea, a cam degree wheel and a crank turning hub. SBC fit over the nut and tightened the set screw on the ridge of the nut.


Than turned the engine to TDC and set the pointer to zero



Rotated the engine one revolution and this was the result



That is one complete revolution plus 90 degrees. So my math comes to 25% over driven . RIGHT??????
Possibly another contributing factor to my ill handling boat?
 

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You want the corners lower in the water than the center, looks like you did it backwards. After the turnbuckles are even with the bottom of the boat, lenghten them all 1/2 turn, then go anpther 1/2 turn longer on the rt outer, and 1/4 turn longer on the next 2 in from the far right, then go to the left outer and lenghten it 1/4 turn longer. When you put the straight edge UNDER the cavatation plate you will have a gap in the center. That makes it trap air in the center and run on the outside tips. When you get it close, you will definately feel what only 1/4 turn can do at 90 plus mph........... thats how I started, marked my turnbuckles with a marking pen and just kept 'tweeking it 1/8 to 1/4 turn until I got all the torque pull out and got it to set. I run 32 gears and a kindswater 11 1/4 15 prop on a 19 flat and twist it anywhere from 6300 to 6700 depending on air and water conditions with a blown 468. I had a hard time getting it to set until I added the extra spring, the plate wanted to 'flap' at high speeds, and I coulden't get it to set with just foot pressure. You have to stabilize it with spring pressure and a stop................ just my long winded .02 !!!!
 

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Ok I have depressed the down pedal and inserted one shim thinking that would be the middle of the pedal movement. Then adjusted the plates as instructed by Violater and this is what it looks like


with a straight edge laid across from side to side there is a shallow v shape towards the middle and then basically flattening out in the middle between the two center rods. The depth of the v is a strong 5/16" {on a side note, after adding the additional turns of the adjusting rods there was very little change to the overall shape of the plate}

So how am I looking? am I OK so far?

I called Casale and talked with a person down there and as I figured just to much time has passed ,he could not find any paper trail on the rebuild. I asked if there is any way to know what gears are installed and the short answer was to split the case. He said I could guestimate by by marking the two shafts and eyeballing a percentage.


So I came up with this brilliant idea, a cam degree wheel and a crank turning hub. SBC fit over the nut and tightened the set screw on the ridge of the nut.


Than turned the engine to TDC and set the pointer to zero



Rotated the engine one revolution and this was the result



That is one complete revolution plus 90 degrees. So my math comes to 25% over driven . RIGHT??????
Possibly another contributing factor to my ill handling boat?
If you have 25 gears, a 15 prop will definately work better........... send it out to Harold Kindswater and tell him what rpms you want to run your motor at and give him all the specs of your boat, for 150 bucks he will bend it and or cut it down and when it comes back it will work..............
 
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