38KV

Where can I get the Cryo-treated gears?

I thougt it was hard to find stronger parts for these old drives.

I don't have any problems yet but I'm going for 8-71's and stellings next year,and I think that's over the limit for my stock drives.

Panther

sutphen30,

Did the change over to bravos effect the balance of the boat? Was it better or worse? E.g. engines are further back, and less weight etc.

I have contemplated a changeover, but then again I will be getting something bigger next year.

panther

force 320

OK DID A FIRST TIME RUN , FIRST TIME IN MY BIG TWIN BOAT!, AND THE DRIVES DID GREAT BUT AFTER 4 STRAIT HRS OF ENGINE BREAK IN I ENDED UP SMOKING 1 OF THE TRANNYS ( NOT COMPLETELY BUT PROP TURNS IN NEUTRAL) SO OUT COME THE MOTORS AGAIN, MAN I AM GETTING GOOD AT THIS.YA GOT TA LOVE THIS SPORT TO KEEP WANTING TO WORK ON THESE THINGS HA HA.

jpclear

Out-drives!?--Trannies!?----If it's a TRS (or anything else) the prop SHOULD spin in neurtal. Pull yourself together! What is REALLY going on here? We can probably help. --- Jer

Oh, by the way; I don't know where you buy NEW "cryo-treated" stuff. The guys that do this process treat whatever parts you give them. If your used gears show "no" or "nice" wear patterns, then have 'em treated! After all, they are tested pieces, and you'll only make them tougher. --- Jer

Panther

Is the prop spinning in neutral and slipping on the top end?

If the clutches are going bad you will feel the trans start to slip at WOT and check the color and smell of the tranny fluid. Try to replace the tranny fluid before you go start pulling motors and doing a lot of extra work.

The trans is fairly simple to rebuild, but if you want a good strong trans with upgraded and additional clutch plates send it to BAM, he is upgrading one of mine right now.

Panther.

force 320

Ok jer Ill try, but heres what hppened. Befor the first run the props would Not spin in nuetral, after the run only R. prop was spinning in N. And with engines off and out of the water the R. prop was twice as hard to turn ( clutch plates warped and taking up clearance and draging), E-Mailed Marc at BAM and he said these trannys are marginal with this set up and sugested rebuilding with graphite clutches. I just want this thing to be relisble all summer, and would rather work on it now while it is all snowey and stuff.

jpclear

Well, Marc IS the man to talk to on this but I just don't know why these units shouldn't turn fairly freely. (there is some drag cause you are turning all the TRS parts plus the output side of the tranny) When you water tested, did the boat tend to creep forward when in neutral? --- Jer

Hang Time 27

JP

Just the fact that panthers rpms dropped suggests that the props were slipping and that the cones helped.

Panther,

The nose cone issue does make sense, along with what kind of props are being run. Adding the cones simply cleaned up the water flow to the props and lessened the amount of slip, thus putting more stress on the drives. possible solution: go to 3 blades if you were at fours......

Every body loves and runs four blades these days for thier cruise speeds, but they just put more stress on the drive. Thats fine for most applications, but for those on the edge with power, it's not helping things. It's just like the guy who finally puts slicks on his street machine and starts breaking rearends, trans', and axels !!! He may have a better 1/4 mile time for bragging rights, but now he's gonna break **** thats "never broke before".....

I blew my single trs this winter (new boat to me) with 625 hp / 700lbs torque, huber 925 trans, with hydromotive 28P four blade, and nose cone. Previous owner got 3 seasons with this power and 28P Bravo one four blade(habits???)

I'm rebuilding that drive to keep as a spare, picked up another that I knew entire history of, and am now going to try a three blade mirage plus. I'll loose some cruise speed, but I don't want to be afraid of my drive all summer.

My previous boat was about 500 hp hooked to a bravo/nose cone with a three blade and I abused the **** out of it for 4 seasons without a single problem. No-one could understand why I wouldn't run a four blade. Meanwhile I was doing hole shots, hopping the boat out of the water just the throttle, etc. - You could feel alot more slip in that setup and I really don't think it would have lasted with a four blade prop......

Huber Transmissions does the same type of trans work. They are basically increasing the number of clutches in the pack and increasing the pump pressure that holds the clutches together. The grafite clutches can survive a little slippage unllike the "paper" clutches that may have originally been in the drive - once they slip under load, they tear and are done... I can only assume that running more pump pressure eats more hp, and that why the factory didn't do it??? Some body set me straight.
damn, I write too much.....

marinetrans

Actually Hubers trans a lower pressure spring (white) than a stock trans (black). The lower pressure does keep the heat down.
He can run a lower pressure because he uses a larger foward servo to compress the fwd. pack. The pump is shaved too and has a wear plate.

Mbam

Extra line pressure is not the answer (been there done that many years ago), the material and number of plates is more important. We have found the cut down pump causes more problems then it solves. No oil flow through the cooler at idle, inadequate pressure when the trans is hot. It is however worth about 5-7ft lbs less loss in the trans. Actually the standard plates are brass which will last a long time in a cruiser application but have a low coefficient of friction (they are slippery). There was a few years that the transmissions that came from Merc with the TRS had the paper clutches and white spring.