I seem to keep breaking this thing in usual ways... screw backed out of M2C diff and did this:

[tetsuo]

There was loctite (the blue stuff that came w/ the tekno) on all 4 screws and 3 are still snug, but one backed out and did this. love that the broken-off screw head managed to lodge in such a way that it dug out a nice smooth groove all the way around. Made a nice slurry of plastic dust and diff oil to clean up!

I mostly run in the grass, and this makes the center diff run HOT, so I used the m2c diff case for better fluid capacity and heat dissipation. Worked great until it didnt! Guess I'll try the tekno steel diff cup next.

 

[Matthew_Armeni]

Wow, that's a pretty crazy break. What oil weight are you running in the center diff?

 

[tetsuo]

Wow, that's a pretty crazy break. What oil weight are you running in the center diff?

100k. The stock center diff cup failed in the first couple weeks of ownership from what appeared to be heat/friction that, in turn, led to a shattered spider gear or two. So when I rebuilt, I used the M2C aluminum cup instead (the tekno hardened steel one one wasn't available at the time).

LIke I said - I run in the grass most of the time and that seems to cause the diff (and everything else, really) to run hot. I see that other people have had issues w/ the screws backing out of the M2C diff, and some speculate that it's because the bottom of the screw holes are open to diff fluid and that interferes with the thread loc. I won't have that issue w/ the Tekno steel diff cup, so I've ordered one of those. hopefully that will put an end to the center diff failures. I'd stop the wheelies and backflips, which I know are hard on the center diff, but then what's the point of picking the MT410?

 

[Klappars]

100k. The stock center diff cup failed in the first couple weeks of ownership from what appeared to be heat/friction that, in turn, led to a shattered spider gear or two. So when I rebuilt, I used the M2C aluminum cup instead (the tekno hardened steel one one wasn't available at the time).

LIke I said - I run in the grass most of the time and that seems to cause the diff (and everything else, really) to run hot. I see that other people have had issues w/ the screws backing out of the M2C diff, and some speculate that it's because the bottom of the screw holes are open to diff fluid and that interferes with the thread loc. I won't have that issue w/ the Tekno steel diff cup, so I've ordered one of those. hopefully that will put an end to the center diff failures. I'd stop the wheelies and backflips, which I know are hard on the center diff, but then what's the point of picking the MT410?

I have the Tekno steel centre diff case and run on 6S with a TP4060 motor in grass. I haven't had any issues with it since installation a couple of months ago.

I make sure that the screws are cleaned with isoproply alcohol then use some blue threadlock.

 

[Nicochau]

I have the Tekno steel centre diff case and run on 6S with a TP4060 motor in grass. I haven't had any issues with it since installation a couple of months ago.

I make sure that the screws are cleaned with isoproply alcohol then use some blue threadlock.

Good for you to clean up the screws! I barely wipe them and off we go for another round!

 

[Sludog]

No issues here with 20+ runs with the M2C center diff and stock oil. I run on grass high and low and dirt and sand mix different days. Although I mostly run 4s because 6s is just too crazy with the backflips and wheelies.

 

[tetsuo]

Seriously... my luck is. Just... wow. This was not even a "basher" battery. It's an HRB soft case 4S, so this was just for speeding around in the grass an on-road. This happened while I had the ESC/radio switched to "beginner" mode (cuts max throttle to 40%) for my sons to drive around:

 

[Gritsngreens1]

Well that sucks.

 

[Sludog]

Dude, your vehicle is possessed. I would call a priest to exorcise those demons. Might be just me, but I would NEVER use a deans connector on anything higher than 3s. I feel the deans are to small to transfer power to the vehicle.

 

[tetsuo]

Dude, your vehicle is possessed. I would call a priest to exorcise those demons. Might be just me, but I would NEVER use a deans connector on anything higher than 3s. I feel the deans are to small to transfer power to the vehicle.

Good point. I noticed a typo in my post and fixed it. This was a 4s. I've checked the connectors and they aren't even warm under heavy use, so at the moment I think the deans connectors are handling the 4S w/ the load drawn by the esc/motor combo I'm running, but I WILL keep an eye on that - it's a good reminder, thanks!

In this case, i think it was just the cheap HRB battery blowing up. My Gens Ace 4S packs will hopefully fare better.

 

[TBuggy]

If all the damage that's done is in that pic and that ESC and servo are still working you got so lucky!

Edit: I am sure the body didn't fair well?

 

[tetsuo]

If all the damage that's done is in that pic and that ESC and servo are still working you got so lucky!

Edit: I am sure the body didn't fair well?

Actually, you're right. A lot of what I thought was damage was actually just REALLY smelly/sticky residue on things. The wires from the ESC, for example, cleaned up pretty well from what was in the pic. The body was OK. At the first sign of smoke, I moved the car over to the stone patio, took the body off, and turned the car upside down. There was too much smoke to see what was going on so I have it a quick shake and the battery just fell out - it had completely melted through the straps and desoldered its own battery leads. Made for easy removal!

Parts that were partially melted or won't seem to clean up fully are just:
- Battery tray
- battery straps
- composite chassis braces (front and rear) and composite portion of diff mount
- left steering bellcrank
- motor sensor wire shielding melted
- stains on ESC and motor power wires

Of those, if I don't mind the smell, only the battery tray and straps really need to be replaced. The rest seem to be structurally intact - just a little stained/brazed on the surface. I was able to dissect the tiny motor sensor wire and re-heat-shrink the line that had melted.

Battery straps are on order - I'll be back to bashing in no time, and waiting for shipping gives me a chance to try yellow springs and smaller (2.3mm) front and rear sways which I think are a better fit for my use!

 

[Sludog]

Moral of the story, don't use cheap batteries in expensive rigs. Cheap batteries are for cheap RC vehicles.