My 'new' Checkmate and its cleaver prop

[twright55]

Hi all,
First of all, I am not a very experienced boater, and I am sure some of my questions will reflect that
A while back I got an '82 Eluder. It has the 470 Mercruiser (3.7l 4cyl) I/O.
It has a 23p Cleaver prop on it. From everything I have read on this forum and elswhere, this is the wrong prop for this boat. These boats need a bow lifting prop and the cleaver is a stern lifting prop.
I have been working on it (replaced the floor, new starter, etc.) and finally got the boat on the water today.
It was doing 58mph (according to the paddle wheel wired to my fish-finder) at 4400 RPM. Cruising @ 3000 rpm registered 36 mph.
I doubt the speed is accurate, but the RPMS are perfect, as the motor is supposed to be run between 3800 and 4400 @ WOT.
AS expected, I don't get much bow lift. I can't plane below 25mph. It gets up on plane fairly decent...a little slow maybe.
I would like to switch to a more appropriate prop, even though the performance of this cleaver is not too bad.
Is there a difference in the effect of a given pitch between a cleaver and a more conventional prop?
In other words, if this cleaver prop is the perfect pitch @ 23, should I stick with a 23 in a conventional prop, or should I go up or down in pitch?
Should I even change props? Is not planing below 25mph normal?
I was thinking of a Hustler prop because it's cheap and I can see if I get much better results.

 

[83PREDICTOR]

I'd be interested in the Cleaver if you want to sell it.

 

[daren34]

prop

i run a 21 pitch on mine for sking
i have the 4bbl version of that motor in my eluder

i run the mirage plus 14 1/2 dia x 21 pitch

i turn 5100 to 5200 all day

the 470 should turn 4400 4800 rpm

the 3.0 litre is 3800 to 4400

you will want a stern lifting prop for slalom skiing

the mirage does pretty good the wakes are big but soft and the boat handles
rough water with ease

good luck daren

i had a vengence prop befor the mirage
terrible prop for this boat f the hustler is a copy of that stay away
you might want a 4blade for skiing i would guess 20 pitch at the most

 

[daren34]

prop

let us know if you want to sell your cleaver

i might be interested

i also have real short fixed trim tabs on mine to keep the bow down

daren

 

[twright55]

i run a 21 pitch on mine for sking
i have the 4bbl version of that motor in my eluder

i run the mirage plus 14 1/2 dia x 21 pitch

i turn 5100 to 5200 all day

the 470 should turn 4400 4800 rpm

the 3.0 litre is 3800 to 4400

you will want a stern lifting prop for slalom skiing

the mirage does pretty good the wakes are big but soft and the boat handles
rough water with ease

good luck daren

i had a vengence prop befor the mirage
terrible prop for this boat f the hustler is a copy of that stay away
you might want a 4blade for skiing i would guess 20 pitch at the most

Hi Daren,
The sticker on the valve cover says 3800 to 4400. Perhaps your 4bbl is rated higher? That would make sense with better breathing capability. It is at least good to know that my motor should be able to turn more RPMS reliably.
I will probably be doing primariy cruising and some tubing and wakeboarding. I think this cleaver is decent for speed w/ just me on board, but I have my doubts as to it's ability ti carry any heavy loads.
I agree that 21p may be better for everything except absolute top speed with no load.

I know very little about what is the appropriate prop for my boat. I had read good things about the hustler/express/razor on this board.

Tom

 

[twright55]

As for selling the cleaver, it all depends on the results I get from any other props I try out. This prop may make a good back-up prop for when it is just me on board.
I think I am going to try a 21p of some other type of prop and see how that goes. But I have not idea what style/model prop to get.

 

[daren34]

props

i like a big round ear for cruising ant tubing

you need at least 14 inch dia in a 21 pitch

i have not tried an of those props yet let us know how they work

i would like to try a cleaver style for top speed on mine

the mirage carries the bow pretty good and will maintain plane down pretty slow 2100 to 2300 depending on load

my brother bigdave has a diplomate stern drive and he found a mach 4blade sterndriver and says it is the greatest prop he has ever run

he has 2 of them a 20 pitch and a 22 pitch
i ran the 20 and it carrys the whole boat higher but i was overrevving
i have not had the chance to run the 22 yet maybe next weekend

if you are at the top of your rpm range you mioght want to stay with 23 pitch depending on the diameter of prop that you go with

200 rpm for pitch change so a 21 would put you at 4800

you will have less slip with a large round ear prop and more cup to the blades
will hold down rpm

props are all a trade off no prop will be purfect for everything
most people keep 2 props one for skiing one for high speed

the sterndrive does not need as much of a bowlifting prop as the outboards
because of the extra wieght in the back of the boat

daren

 

[twright55]

Well, thanks for all the advice.
I think I will try a 21p Hustler. It might make a good prop for when I am full loaded and/or pulling tubes, etc. If the hustler works out for those purposes, I will probably keep the cleaver for cruising when it is just me on board.

 

[Diplomat82]

All this prop talk got me thinking I my need a new prop for my Diplomat. I called Mike at Checkmate to order some parts and I asked him if he had any thoughts on props for the 470. He told me he would get a Turbo 1 prop 14.25" Dia and 23 degree pitch. He said that prop is a great all around prop for that boat.

I'm running that same pitch but in aluminum and have been happy, but I understand that a stainless's blades are thinner and don't flex like an aluminum.

Anyone have experience with Turbo props?

 

[Big Dave]

Hi
Daren34's brother here (we are twins)
Is your 3.7l a two or 4 barrell carb?
4 barrell has more top end power and can pull a little more pitch
I had to remove the 3.7 from my diplomat(bad block) and had a v8 sitting around so I now have a fairly hot 350.(lots of fun on that swap) I am turning 5700+ rpm with a 22p 4 blade prop so for top end I need way more pitch.

I do love the way the Mach Sterndriver 4 blade carries the boat.

we use it mostly for tubeing and skiing with the occasional Hi-Speed pass to show off.
Trying to talk Daren into a v8 but he can go to the lake 3 times before refilling the gas tank and we fill up everytime and my son has had to pull the boat out and go fill it up before!!!!!

 

[Big Dave]

Turbo

I'm running that same pitch but in aluminum and have been happy, but I understand that a stainless's blades are thinner and don't flex like an aluminum.

Anyone have experience with Turbo props?

Daren had one on his outboard diplomat when he first bought it. loved it untill the lower unit grenaded and the prop went to the bottom of the lake
when we bought the new motor, they threw in 2 omc raker props with it.


daren is turning 5200 with the 21p mirage, so if you have the 4bbl, you should be fine with 23p. 21 or 22 depending on cup for water skiing but have to watch rpms to keep them down
3.7 does seem to like the rpm. no problems so far with his( 1 1/2 yrs with that prop now)

 

[twright55]

Hi
Daren34's brother here (we are twins)
Is your 3.7l a two or 4 barrell carb?
4 barrell has more top end power and can pull a little more pitch
I had to remove the 3.7 from my diplomat(bad block) and had a v8 sitting around so I now have a fairly hot 350.(lots of fun on that swap) I am turning 5700+ rpm with a 22p 4 blade prop so for top end I need way more pitch.

I do love the way the Mach Sterndriver 4 blade carries the boat.

we use it mostly for tubeing and skiing with the occasional Hi-Speed pass to show off.
Trying to talk Daren into a v8 but he can go to the lake 3 times before refilling the gas tank and we fill up everytime and my son has had to pull the boat out and go fill it up before!!!!!

Hey Dave,
I have the two barrel. I would like to convert to 4barrel if it will really make a difference. I have a rebuilt quadrajet laying around already But it is an 850cfm (truck) version...might be a little overkill for a 3.7L!
And then those 4 barrel manifulds are not cheap when they turn up on EBAY.

There are SO MANY different props out there, it is hard to make a decision as to which one is the right one.

Tom

 

[Big Dave]

I think the 4bbl would be a good step, the swap is not hard, but you do have to change the valve cover as the throttle cable sweeps around the back of the motor and then over the middle to hook to the carb.]
When I went to the v8, we switched the throttle and shift cables to make the length work right.
sorry about the 48mph, but for a 19ft boat(compare to 21ft with built in platform ie...bayliner, welcraft, glastron) with a 4cyl, pretty good

daren34 has the exact boat exept he has the 4bbl carb.
Your motor is half a 460 ford, custom aluminum block by merc, custom crank, 460 rods, 460 pistons, 460 pre-emission head(you can drop an egg down the intake ports) 1.7 x 1 rocker arms(chevy is 1.5 to 1)420 lift cam
There are stories of the legends racers using them to make 700 hp in 3/4 scale dirt track racers.

 

[Eaglenva]

I would like to convert to 4barrel if it will really make a difference. I have a rebuilt quadrajet laying around already But it is an 850cfm (truck) version...might be a little overkill for a 3.7L!
Tom

Careful on using vehicle carbs on boats, i think that is a no-no. ask around but i don't think it meets coast guard regulations to prevent fire, etc. i dont know the differences but heard - distributor, starter, carb, etc must be marine to be safe.

todd

 

[Big Dave]

electrical parts are supposed to be sheilded from spark emmisions, fuel parts are set up to put stray fuel vapors into engine instead of vent to atmosphere.
even air filter is not a filter but a spark arrestor
Fuel vapors and stray spark----what could be better in a hot closed-in space