Had this bravo built 5 years ago it now has around 60hrs on it, when i looked at it the retaining nut seamed to have backed off and cause excessive gap between the gears, i could push and pull the input shaft at least 1/8th inch of play, and you can see from the picture of the gear teeth that not 100% of each tooth was in contact and probably caused the failure.

this is on a 1988 checkmate 251, 700hp, 509, blower, 88mph, bravo labbed 30p, 1.5 ratio
always babied it out of the hole, never went past 1/4 throttle when planing off, outdrive broke on a smooth full throttle run.

Any ideas?

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By the looks of the string of threads sticking off the spanner nut it got pushed out. You're putting 700hp to a bravo, be happy you got 60hrs. What happened here is the drive isn't built to withstand that power.

Lil red, this drive was built to handle the power, by a reputable company who I am not going to mention right now, came with 2 year warranty, cryo gears and case and some others, I just want to make sure something else wasn't wrong, I dont think 60hrs on a drive like that is enough.

Am I missing something? Everything looks normal for a Bravo.

I will go with what Lil Red said....and they didnt even use a good seal retainer.

No one and I mean NO ONE will build you a standard bravo 1, with the stock retainer ring/spanner nut for 700hp. I can't think of many that will build an xr and tell you it will live on that environment! Those are stock gears I don't care what they are treated with and the ring is cheap stock aluminum intended for a 23' sea ray bowrider

i agree with everone one else here ..i dont know anyone that will build a bravo with that retainer or those helical cut gears and honestly
tell you its good for 700 hp ..does he offer a warranty if you use good parts ..meaning steel tower straight cut gears and good retainer ???

Any drive shop or drive tech needs a good bartender or a good psychiatrist!
If you are running high H.P. or big boats it is going to fail, just a matter of time.
That drive broke the pinion gear,that loose part got stuck between the pinion and one of the driven gears.
The pinion got pushed so hard it just came out the front of gear case.A steal retainer nut might have helped.
In one of the pics it looks like stock,small,old school ujoints.

mac

It could have been worse...you could have broken the case right behind the threads if you had the better retainer.

Probably right BUT I have 2 drives for my boat that both have steel max worx retainer rings and they say that the retainer pushes out and causes this to happen, I have over 400 hours on my main drive with 650-1100 hp pushing my 272 Baja and have not had a retainer push out yet fwiw, xr upper gears too though, Smitty