Lower Unit questions from less experienced Member

[Cervelo777]

I have blown up two coned torquemasters in the first 15 hours of my High performance boating, which has led me to the following questions. By the way I am running a modified 260, 15" on and Allison XB03, best I have seen so far is 95 mph at 7200 RPM with 28p Mazco RE3.

1. When lower units fail, how often are they completely trash, meaning no salvageable parts?
2. What is the average lifespan of a coned torqumaster, and do sportmasters last longer.
3. can you add the torque tab back to a sportmaster, if it has been removed. I don't want something rivited or screwed, seems like welding would be legit.
4. I didn't think I was the guy that needed a billet bearing carrier, or heavy duty reverse gear, but maybe I am?


All thoughts, experiences, and stories welcome. Thanks for your opionions and advice.

[Bodhi]

1. Lowers fail differently in most cases, ive had lowers that just need something as simple as a carrier assembly to seeing the pinion gears blown right through the casing.
2. Cant really put a lifespan on lower units when they are being used for high speed/high performance, but I do feel strongly that a sportmaster or CLE handles power a lot longer than any other lower.
3. Try to avoid welding or purchasing welded lower units, they will be more prone to failure under the stress of running high speed. Welding creates heat affected zones which are the weakening of metal surrounding the weld.
4. You running a 28p round ear puts you in the category of us who need to start in gear and not shift into gear while running to save the clutch dog from burning out/stripping. My original 1998 CLE lower unit has lasted me this long due to starting in gear and frequent oil changes every 10 hrs.

Hope this helped, any questions.....someone on here knows the answer

[transomstand]

Just an FYI, Torquemaster and Sportmaster internals are identical except the Sporty has an extra bearing on the driveshaft. There should be no significant difference in longevity. Never run a used gearcase without first having it gone through by a good case builder, there is LOTS of junk out there. Most of this stuff is 20 years old or more, and surfacing the prop is very hard on any case. I'm also in the 10 hr. oil change club, helps keep an eye on things.

[Krazymaan]

CLE lower unit has lasted me this long due to starting in gear and frequent oil changes every 10 hrs.

Hope this helped, any questions.....someone on here knows the answer


:eek:

[90 5.0]

My sporty outlasted a power head that gave up at 450ish hours, 200+hrs later it gave up.

So mine went 600+ hrs being above the pad it's whole life on two different boats, and was never started in gear until after it blew, now I always start it in gear.

Its had everything from 20-30" pitch props on it. Was run on an xb2003 for most of its life then on a heavier 20xdc bullet now.

15hrs on a lower is not acceptable, it was either damaged in the coning process or the lower unit builder is not competent or you rev it up and pop it in gear like dumping the clutch(highly unlikely but covering the bases LOL)

my my cle has never blown up, I put fresh bearings in it two years ago just because and everything that came out looks good. I have no idea how many hours it has on it, it was used when I got it many many moons ago and has been on I've lost count of how many of my boats.

Change the oil frequently(I normally do once a season or sometimes twice if I've been really hard on them) and they will live fine, especially once you set them up to start in gear when running bigger props.