mxz800

the boat is a 259 checkmate with 7.4 385hp went from a 23p 3 blade mirage plus to a 24p 4 blade hydro that has been slightly labbed. boat would turn 5000 rpms with the mirage and sometimes hit the rev limiter with light load cool day slight chop. with the hydro the ride is GREATLY improved but can only pull 4400 rpm with light load chop 80degree day. i know i should of went down on pitch but got a good deal and figured i could get this one worked. big problem is having hard time planing with four blade but never had a problem with the 3 blade, doesnt seem to have enuff grunt to get the boatover on plane. is this a side effect if having way big prop and what should i do to get my prop into my operating range?? thanx guys

Cord

The prop is simply too large for your application. You won't be able to cut enought pitch out of it to make up 600 rpms. You'd be better off just buying a smaller prop than to try to rework the one you have.

Usually, the problem with the hydromotives is that they slip or blowout when planing. If you don't have that problem and instead the prop is hooking up too well so that it bogs your motor, then you must have a really deep x-dimension. Until you raise this is just going to be the cost of having too large of a prop with a deep x.

I'm just wondering if this really is the correct prop for your application. Have you calculated the slip percentage yet? I'm thinking that your application would be happiest with a round ear prop.

wild willy

mxz;i agree with cord that you have to big of a prop for your boat!! i have same hull as you and i have 500hp efi motor. i turn 5100rpms with a 25 pitch labbed hydro.you can have the pitch reduced for about 300rpm gain,but still may not be enough for you! call tom at hydromotive 330-425-4266 here is another thing to do call checkmate factory and talk to mike or kipp about a new prop they have been testing with good results it is made by turning point and is called speed zone made in florida 419-562-3881 a friend of mine tryed this prop and loved it on his 270 convincor. hope this helps you bill

mxz800

thanx for the replys i will call checkmate and find out about that new prop. is that a 4 blade 25 you turn? i am not sure which is my biggest problem lack of horsepower of deepX i compared with someone onhere same hull and mine was an inch deeper than theres. is it the fourth blade, the straight blade edge design(versus round ear) or just design that is giving me this stern lift with the hydro versus the bow lift with the mirage plus?

Donzi26ZX

MXZ, I have the same problem with my Donzi 26ZX with the same motor, I am selling my motor and putting in a 500 EFI. I tried the 22 pitch 4-blade and it works great but I lose to much top end and would rather suffer out of the hole than lose it on top.

mxz800

donzi you lose to much top end with the 22 4 blade compared to what other prop and how much mph did you lose?

Donzi26ZX

I probably would say around 6mph or so, it gives me a great hole shot but I like having the top end. When I have 4 people on the boat forget about planing off in a hurry, the boat is a snail!!!

dockmech

first off mxz800s dont have props. you must ride sleds. I had a 253 convincer with a 502, I tryed all kinds of props the best prop for those boats is a mach but they are out of business. I used a 141/2x24p the rpms were 4800 and this boat would handle. this may give you some idea about were to go. to be truthful this prop went back to the factory at least six times. but when we were done the prop did what I wanted, so you must know what you want with out wanting to much.

mxz800

dockmech yes i have had a few sleds. i am starting to think the perfect prop is made not bought right out of the box. sheesh i thought sled clucthing was tuff

dockmech

I just bought a pair of 28 hydromotives off this for my 29 fountain It will be interesting to see how many times I have to send these back if they are close. I am in up state N.Y. and had mike spinnelli do my props but I hear he has closed. If you told him what your boat was doing and what you wanted it to do , he would make it work if he thought he could with out going to another prop. by the way we ride polaris all over up north.