BMAX outdrive problems

[offshore racer]

I have a 604 hemi making 1200 hp and I have a BMAX out drive. The problem is that I have snaped clean twice the 1 1/4" shaft on the drive just above the gear. Once with a Herring 6 blade 33 pitch and with a Mercury 4 blade 30 pitch Lab finish prop. Has any one else run a BMAX that has had the same problem?

[don johnson]

Yup. Lots of problems this year.
Dean is having heat treating quality control issues. Contact Ron at Bad Attitude Marine in Parker, 760-413-4263. Ron is the B Max dealer on the West Coast. He is using the Max Machine Works shaft because of the bad run of B Max shafts...
Ron does all the work on my 33' Daytona with 2 1050 HP Teague motors and B Max's.... He runs a stand up shop.

[HP350SC]

I have a 604 hemi making 1200 hp and I have a BMAX out drive. The problem is that I have snaped clean twice the 1 1/4" shaft on the drive just above the gear. Once with a Herring 6 blade 33 pitch and with a Mercury 4 blade 30 pitch Lab finish prop. Has any one else run a BMAX that has had the same problem?
Keith ( Robbie Racer on the boards) has had his fair share of various b-max problems and could give you some good info. as well.

[79 HUSTLER]

I have a 604 hemi making 1200 hp and I have a BMAX out drive. The problem is that I have snaped clean twice the 1 1/4" shaft on the drive just above the gear. Once with a Herring 6 blade 33 pitch and with a Mercury 4 blade 30 pitch Lab finish prop. Has any one else run a BMAX that has had the same problem?
My .02 cents is that if you have run with that much power for any amount of time you are fairly lucky that is all you break. 1,200 hp is alot of power for anything to handle, short of a #6 style drive. Now if they are breaking as soon as they are hitting the water then it may be the above mentioned problems with the bad shafts???? But with any big hp number there is not much in the drive department that is industructable. KELLY

[Evo22]

sounds like it could be a perfect platform????? :p what knid of hull? are you running a standard or 2"shorty lower ?

[Boatlesss]

What happened with the guy who switched from a Bmax to a Wiseman?

[Evo22]

hes is still working on it he is waiting for some shafts to come back from heat treating,

[79 HUSTLER]

Update-- Just snapped my second shaft as well on saturday. In the same spot as yours just above the gear. Second shaft this year and with not nearly enough hp to phase a B-Max drive. Went to get on it while passing the sandbar and it did not work like I had planned. Starting to wonder if my choice for a B-Max was a good one or not???? KELLY

[don johnson]

Have you looked into a Max Machine Works shaft?

[79 HUSTLER]

Have you looked into a Max Machine Works shaft?
No I have not figured out what I want to do yet. May just let the boat sit till winter time when the real power gets put in, and try to justify a wiesman. Is a max machine shaft what you are going to install in yours this time, what is the cost of a max shaft, maybe I will just buy a few of those and always carry a spare. KELLY

[Evo22]

hey hustler i PM'd you...I have a fix for all of this i just need a little time on the drive to check out wear

[don johnson]

No I have not figured out what I want to do yet. May just let the boat sit till winter time when the real power gets put in, and try to justify a wiesman. Is a max machine shaft what you are going to install in yours this time, what is the cost of a max shaft, maybe I will just buy a few of those and always carry a spare. KELLY
I have yet to break a B Max shaft. However, mine were built last year and B Max did not have the problem then. In talking to Ron at Bad Attitude, the B Max dealer in Parker/ Havasu he said that this years run of shafts from B Max have been problematic. He has started using Max due to the faulty heat treating...
And yes, if I break one I will use the Max shaft.

[gmocnik]

so evo22, whats the deal with the drive you keep reffering to???
inquiring minds want to know....

[offshore racer]

My hull is a Rayson Craft 26' Cat Tunnel. The bottom is the same as a Talon Cat. Both shafts snapped clean when the boat was around 4000 rpm. Thank God for rev limiters. The 604 Hemi makes 1000 ft lbs of torque at 2700 rpm. Dean replaced the first shaft. I have expressed my displeasure with the shaft breaking both times :argue: . I know that he will replace the second one. Normally the upper end blow up on drives not the bottom. I am really considering going to an Arneson drive.

[hulshot]

Offshore racer, this makes now 2 Raysoncraft 26 cats on the boards now. The other is Racer52, he has a Quad rotor BBC EFI and runs a ImcoSC and has run it hard!!!! with 1.25 gears and has yet to break. That boat should be a light boat and sould come on plane quick, and at 4000 rpms you should be cliping along in the 80's or higher It may just be a faulty shaft. Good luck, I only run Imco drives. There is a 4x4 drive for sale that is fairly new and a new rebuild with 1.22 gears. Call Rockit man (Wayne) he still has it.
What is up with EVO 22, you keep talking about a fix but people PM you and they still have the same drives. Whats the scoop and what is you big problem solver drive all about???? If it is that good I may want one.

[Robbie Racer]

Offshore Racer: I have around the same power in my 25' Carrera cat. The boat and motor weighs about 4,500 lbs with about 20 gallon of gas on board. (Not counting people and gear). I have broken a couple of vertical shafts and a couple of prop shafts in my B-Max. You have had better luck that I have trying to convince them to warranty these shaft breaks. So far this year, I haven't broken any more shafts (now looking for some wood to knock on). I don't think there are any stern drive's out there that will take that much power (especially if you hammer it in the peak torque rpm range) very often.

[Rock-it man]

The Weisman drive is holding up fine ,I put 10 lbs boost to it and hammered it a lot and its still there !!!!!!!! This week end i'm going to 15 lbs at Shasta and see what happens my only issues is finding props to try there is not a lot of small diamiter props for a (#6 type) setup using 16 to 16.5 and 29-34 pitch to see what it needs, the best prop I had for the IMCO 4x4 was a Hydromotive 15.5 x30 five blade and it ran 141.9 @ 6400 rpm . So far no handling issues but have not got over 110 mph yet. The video at 110 shows a the bow riding a little higher than before ,will video it as I increase the speed to see how it sets in the water.Will run it up to around 125-130 this week end if the props I have work.

[BADBLOWN572]

I am having the same problems too. So far I have snapped 4 B-max'es and I am sending the most recent rebuild back to the Bravo Shop because I now have no neutral. 2 hours on the drive and I loose neutral. They estimate that when it was last rebuilt, some of the debris got up into the cone clutches and also took out the "bump" disks (???). I have snapped the 1 1/4" shaft clean through three times and one time it broke almost everything in the drive (upper gears, lower gears, etc...) It was bad. I am putting out 985h.p. @ 5k RPM.

[don johnson]

BB572,
Have you spoken to Ron at Bad Attitude in Parker, 760-413-4263? He really knows B Max's well and may be able to help.... I have had the same problem except I keep losing reverse in my port drive....

[BADBLOWN572]

I have talked to Ron quite a few times. He was the one that rebuilt my drive last time. I have talked to him about it and he was saying that it was a heat treating problem with B-max shafts, but doesn't know why I lost neutral. I talked to Dean over at the Bravo Shop and he wants to take a look at the drive personally and rebuilt it this time and he said that he would probably do it under warranty. We will see.