Rear gear case cracked...any ideas....how, and what to do?

[Steve Vanvelzen]

I have a 2021 Massimo T-Boss 550 which now has a crack in the rear gearcase. A few weeks ago during my usual fluid checks I noticed that the gear oil was very low and there was an oil film on the outside of the case on the side where the plug is. I topped up and cleaned it up. I assumed the the bolt was not sealing properly so I ran it as usual and same thing again and again. So then I was thinking that maybe I need a new washer or something. I cleaned the outside of the casing and was about to top up the oil when low and behold.......I noticed a crack across the top right side. OMG, this thing is only a year old. Any ideas out there on how this would happen and most importantly....how can I fix it?

Any advice would be appreciated because as we all know on this forum it is hard to get shops to work on these wonderful machines. And if I need parts, wish me the best of luck.

[TapBoss]

The way they are set up I think you can rule out being over-filled.  Sounds like it has still been running so something cracking it from the inside doesn't sound plausible either.  My guess is a weak spot in the case when manufactured.  Other than a replacement, I'd probably opt for Industrial Strength JB Weld (depending on how big the crack is).  I've seen guys fix automotive tranny's with that stuff.

[Steve Vanvelzen]

Thank you for the response TapBoss. Funny that you mentioned JB Weld, I watched a dozen Youtube videos on it this weekend and went out to buy some yesterday. The crack is on the top so hopefully this patch will keep me going for quite awhile. It kinda looks like there was a crack in the manufacturing die; not sure if this thing is forged or cast but it is a long crack and parts of it protrude outward

[TapBoss]

Hope the JB works out!

[Ridge Runner]

I’ve had great luck with JB weld.  I hope it holds for you, let us know

[Steve Vanvelzen]

So far, so good, let hope it lasts though