9XL & Mamba Max Shut down! - RC-Monster Forums

05:48 AM

Hey I've been trying to tune my combo recently and been having these problems:
- ESC shuts down after 2 min. of runtime then it would re start
- drilled my pinion to fit the 5mm shaft of the 9xl and lost 2 grub screws already.(I shaved of some meat on the 9XL shaft so grub screw has something to bite on)
by the way my gearing is a 77t spur and 18t pinion
any ideas on how to correct these issues? by the way im still using the stock settings for the MM. Also for your info i'm only using 2x 3300mah ni-mh 7.2V. Would appreciate some help thanks. And if there's any old threads about this pls. tell me which one thanks

Nick · 11.17.2006, 06:22 AM

Does it get hot? No lose connections?

Locktight in grub screws?

11.17.2006, 08:54 AM

it gets hot but not so cause i could still touch the motor and esc. i dont think its a loose connection cause i wouldnt need to touch anything for it turn on again

11.17.2006, 08:55 AM

tried to locktight the grub screw yesterday and still lost one today

glassdoctor · 11.17.2006, 10:40 AM

Check for any "error code" flashes on the esc when it happens....

rotary rocket · 11.17.2006, 10:49 AM

Quote:

Originally Posted by carlog80

tried to locktight the grub screw yesterday and still lost one today

Let the locktite dry over night before running your truck.

Try to drop 3-4 teeth on the pinion to see if that solves your problem.

Finnster · 10:52 AM

Sounds like a thermal to me... Can you measure the temps? Or as DR said, any beeping or error codes?

What's the gearing?

Do you have a fan on it, a fan is a must. BEC is disabled as well?

skellyo · 11.17.2006, 11:23 AM

I highly doubt with his 18:77 gearing that it's misgeared enough to cause a thermal problem in that short of a time period. I would be more inclined to believe it's thermalling due to the pinion slipping on the motor shaft when the grub screw falls out.

Finnster · 11.17.2006, 11:31 AM

Quote:

Originally Posted by skellyo

I highly doubt with his 18:77 gearing that it's misgeared enough to cause a thermal problem in that short of a time period. I would be more inclined to believe it's thermalling due to the pinion slipping on the motor shaft when the grub screw falls out.

Opps missed it... Yeah you're right. Its actually geared lower than my 8xl. The prob must be somewhere else. 2 min awfully fast...

What typr of driving are you doing? Grass, street etc?

11:49 AM

been driving on grass. im kinda simulating my runs on a race track cause our nationals is cming up and im trying to tune my truck. by the way how would i knw what the erroe sounds like on the esc?

crazyjr · 11.17.2006, 02:06 PM

I think 18/77 wouls be too low geared and it would run very slow and might be over-reving. How did you get a 77 tooth spur gear? and what tires are you running?

Can you give us all your setup for the motor and esc?(include the tires as well)

I have run mine with 40 series wabash and bowties, with 17/66 gearing and 12 cells with no trouble for over 15 minutes, with 4.4k's from Maxamps and the only problem i have had was going to a reciever pack because the internal BEC couldn't keep up (expected), but i haven't had trouble with heat or cogging like some others have described.

Serum · 11.17.2006, 05:38 PM

Seems to me that you are not using an external UBEC/receiver pack.

I had that problem with 8 cells on the MM, i am using a very enthusiastic servo which takes quite some power.

BrianG · 11.17.2006, 05:41 PM

Good thought Serum. Carlog80, you can see if this is the case by turning the ESC on and just turning the wheels back and forth and see how much the ESC heats up. Since the BL motor isn't running, the only heat generated will be from the BEC...

crazyjr · 11.17.2006, 06:21 PM

Or just put a battery pack on the reciever and remove the middle wire from the plug.
running 12 cells on mine it would cut, but it would come back on almost imediately, I didn't push it so i don't know if it would stay shutdown for a time if the heatsink got too hot

riceman · 11.17.2006, 06:30 PM

Quote:

Originally Posted by crazyjr

Or just put a battery pack on the reciever and remove the middle wire from the plug.
running 12 cells on mine it would cut, but it would come back on almost imediately, I didn't push it so i don't know if it would stay shutdown for a time if the heatsink got too hot

And if you'd rather not cut wires on your rx or esc you can get an short extesnion and do ths