Big Block Billy

I'm refering to the driveshaft in the lower gearcase. BBB

articfriends

iTrader: (1)

Ok,I'm not sure if your talking about the vert shaft or prop shaft but I have a std dia max worx prop shaft in one drive (they didn't have the bigger one yet when I bought it) and a maxworx xr size prop shaft in the other drive,haven't ever broke either one.I have sheared off one of their billet torsional shafts and funny thing was I only had about 725-800 hp and about 800 ft lbs of tq at time BUT i was on and off the throttle like a retard screwing around,Smitty

Big Block Billy

I've really been thinking about the problem you are having with the lower gears. I think some of wear is from the propshaft deflecting/twisting. (plastic deformity)
Notice a Speedmaster lower, like a #6 , The majority of the propshaft is supported by many caged needle bearings that are lined up, not just 2 or 3. Maybe a change in bearing carrier design to add more support to the shaft, and the wear will decrease. BBB

articfriends

iTrader: (1)

I think if that was the case the gears would hold up better in my spare drive that has bigger xr max worx shaft and billet prop carrier. I'm going to try running 140 wt gear lube from now on too and see if that helps. I was running some exoctic stuff max worx swore by but they wouldn't tell me the weight. Motor is swinging in the air right now,inspected the upper in my drive fri night that is going to be on boat for the test,gears still look like new. Bought angle finders,stainless bolts and longer water hose fri,hope to have motor sitting back in boat and lined up by tommorrow night with the stellings box on,Smitty

articfriends

iTrader: (1)

Update on gear experiment-I have ran boat 6 hours now,hasn't spit teeth off lower gears and NO metal in lower unit oil YET. I have only ran it at wot though for a few 15 or 20 second burst but have cruised at 4000 rpm's with 30 pitch 4 blade. Hope to whip on it a little this weekend and see whats going to happen,Smitty

Mr Gadgets

Go Smitty Go!!!

Ratickle

Keep us informed. Good luck!!!

In2Deep

I'm not a wrench, and not very educated when it comes to these kinds of things -- but I do like staying on top of the technical side of things, and becoming informed on what I can, just in case the info comes in handy down the road.

I just had my upper gears let go two weeks ago on my Bravo Ix. Max inspected the lowers and said they still had life left -- which to me means I'll be buying lowers soon. So, I'm diggin' this thread. Fascinating.

I2D

articfriends

iTrader: (1)

Was going to make 15 or 20 1-2 mile wfo passes today,bay had perfect water within 1 mile from shore,boat had 5/8 tk of gas,had 32 pitch labbed prop on,leaned on it expecting to see at least a 95 mph run with new exstenion box on it, boat only pulled to 5400rpm's/89.6 mph,something was screaching,stopped,Frickin supercharger impeller disentegrated . Pulled hose that connects innercooler to throttle body,tiny bit of aluminum made it to motor,hopefully not enough to hurt it,pulled supercharger belt off,limped it in,gave up for the day. First time I have had any kind of problem from the actual procharger head unit,she's mangled! Now the scramble to fix it begins ,Smitty

Mr Gadgets

That sucks Smitty.. sorry to hear that..