Stealth Goes BOOM!

[LTO_Dave]

I finally took a pic of the Stealth that grenaded in my brushless RC10 runner. I ran this tranny for months with NiMh packs and a 13T brushed motor, then a 27T motor with zero problems. After I rebuilt it with a new RPM 2.65 conversion, diff rings, diff balls, thrust balls and thrust washers, I ran 8-10 LiPo's through it with a 18T brushless motor with zero problems. The diff was always buttery smooth and it never made a noise and ran great. The stock slipper was set perfectly with a new disc and updated thrust bearing, and never acted funny. The end result is broken diff ring fragments that embedded themselves into the other gears and made quite a mess. Luckily I stopped the car right when it happened.




I replaced it with a TrackMaster belt-drive tranny without a slipper, and it ran great with the same LiPo/brushless combo that's now in my B44.

[THUNDERSTRIKE1]

DANG DUDE!! Thats the worst stealth damage ive ever seen from one tranny.DON

[flipwils11]

I expected to read that it was a 5.5t motor or something.... Very surprised (and concerned for my modern racer build that I was going to run 10.5t in).

[RichieRich]

This is awesome. What kind of sound did it make?

[LTO_Dave]

I expected to read that it was a 5.5t motor or something.... Very surprised (and concerned for my modern racer build that I was going to run 10.5t in).

I wouldn't be too worried about running a 10.5 based on what others currently run. Maybe it was just a bad batch of diff rings or diff balls. I'm very meticulous about my tranny and this one went together perfectly and was super smooth. It never made a sound up until this happened.

This is awesome. What kind of sound did it make?

Nothing crazy, just a slight grinding noise like when your motor comes loose and the pinion hits the spur, which is what I actually thought happened. It coasted for only a few feet once I lost power.

[Charlie don't surf]

I had a set of AE rings do the same thing with a 6.5, I caught it when it starting clicking during a race

[ratdude]

I am not shocked at the damage to the the diff gear or the idler , but that pinion , WOW

[EvolutionRevolution]

The diff balls weren't melted into the diff gear?

I've never seen fragmented diff plates like that...

[LTO_Dave]

The diff balls weren't melted into the diff gear?

I've never seen fragmented diff plates like that...

Nope, the diff balls and holes in the diff gear looked fine, so it doesn't look like anything overheated.

I've seen some diff rings that were deeply grooved, but never broken like these ones.

[Coelacanth]

This is awesome. What kind of sound did it make?

A booming Stealth doesn't seem very stealthy.

[Dave145]

It would almost appear as if a tooth broke off of one of the gears and jammed up the tranny just enough to take out all the other gears. Ive had this happen on another car that I own where a tooth breaks free (it looks as if it came off the idler) and got caught in the gear teeth between the idler and diff gear and the idler and top shaft. I'd only guess that the idler went out first because of the way the teeth are "cut" on the other two gears and broke on the idler. Almost as if a center piece of the tooth chipped off, got caught in between two good teeth, then started werong down the surrounding gears. The "step" on the left side of the diff gear would prove that. I have a gnawed up top shaft for this same tranny that looks like it somewhat survived the same thing (just scratches and grooves on the teeth, no entries cavities. As for the diff rings, vibration may have causes them to break, but what looks more probable is that again a gear chip made its way into the diff beside the rings and the force of the wedged piece scraping the diff ring was too much for it or if it was pressing the ring to the side of the gear causing it to grind up against the side of the diff gear. (this would hold true if the diff was fine after all this damage.) When you look at the diff gear, are there any cuts inside of it where the diff rings sit? That might prove how the rings ruptured. Otherwise it may have been heat, but im bot too sure about that.

I can't believe that would happen with that mild of a brushless system... Makes me want to rethink putting my castle creations sidewinder sct system back on my stealth gold pan... Good luck.

[teman]

Same exact thing happened to me recently

TO ME it seemed I burned up the diff lube and the friction in the diff started cutting the rings up to where pieces were circulated into the rest of the tranny chewing it all up. I'm just speculating, not really sure what happened exactly. I was running 7 cell nimh with the Asso/reedy combo sc450/3300 kv.

[Jedi Master]

At least you did it in style! Lol!

[slapshot1979]

That earns the KABOOOOM award of the week. Well done. even though it sucks when it happens

[AscotConversion]

It pays to upgrade the idlers to the new natural colored gear. The old black gears don't stand up and this is the result. I have had a similar thing happen in a BL dirt oval car I used a black idler in.