Brushed motor replacement(Senton 12t)

[RCmc7]

Well we couldn’t resist driving on a wet soggy day and the motor burned up on us. Reading voltage on the leads, I read 5.4v from the esc and no response from the motor. Servo is moving. I guess we are done!

Now looking for a replacement for my son. He really doesn’t need any serious upgrade because it’s fast enough. I have done lots of searching here and realize the overhaul we will need to do when we move to brushless.

As for now we would like to keep it low cost and easy. Could someone help me understand the differences between:

550 vs 570

12T vs 9T

Any suggestions on something that might give a better acceleration?

 

[kaladeth]

Well congrats! I would probably have done the same thing, never let anything get in the way of a good bashing session .

Not sure how you diagnosed the motor as bad; made me curious what kind of voltages should be. I would expect 7.4V to 8.4V (2S) but nevertheless a low reading like that seems to indicate more an ESC or battery problem than an actual motor problem.

Are you planning to replace both the motor and the ESC?

What pinion do you have on right now? Is it the stock 17T? For quicker acceleration you can maybe try a smaller pinion (maybe a 15T?).

The 570-9T seems to be a bigger motor but I can’t find kV info on either, so tough to say if it will be quicker. It does have bigger connectors (4mm vs. the 3mm on the 550-12T).

Hope others can chime in! Good luck with the upgrade.

 

[RCmc7]

Not sure how you diagnosed the motor as bad; made me curious what kind of voltages should be. I would expect 7.4V to 8.4V (2S) but nevertheless a low reading like that seems to indicate more an ESC or battery problem than an actual motor problem.

I am just assuming its the motor but I really don’t know. The steering works and the 2 fans are running. I clamped on wire piercing leads from my meter and it read a small voltage and the led on the esc lights up when giving it throttle. Maybe I need to dig deeper? I added a cheap 2 fan mount to the motor just before letting my son drive it. Could that be the issue.

I unplugged all fans and the car wouldn’t move.

 

[Reverendg]

It does seem more likely to be the esc. The motors can be run immersed in water to break them in. 5.4 is a low voltage. Do you have any dc power supplies? Not sure how adept you are, but you have a decent multimeter, so you may try a direct battery voltage to the motor leads, with the wheels in the air. Just a second or two, to confirm the motor is good or bad. Disconnect the motor from the esc first.
Motors are pretty easy to get, turns affect the power output of the motor. In general less turn goes faster.

 

[RCmc7]

It does seem more likely to be the esc. The motors can be run immersed in water to break them in. 5.4 is a low voltage. Do you have any dc power supplies? Not sure how adept you are, but you have a decent multimeter, so you may try a direct battery voltage to the motor leads, with the wheels in the air. Just a second or two, to confirm the motor is good or bad. Disconnect the motor from the esc first.
Motors are pretty easy to get, turns affect the power output of the motor. In general less turn goes faster.

Just came back out to mess with this. It was late last night.

I do have 8.4 volts leaving the esc. I will put battery to motor test now.

No response for motor connected straight to battery. Now to a replacement lesson!!

 

[Reverendg]

The motor it is. Check Amazon for the same turns, a few few less if you want a little more go. Don’t worry about brand, just a 540/550 with leads. Typically about 15 bucks. I just put a 12 turn in my Rustler. The 30 year old 20 turn finally ate its brushes.

 

[RCmc7]

Going to post this in the appropriate section but this area seems like a not so great gear to gear mating. When I turn the wheels it felt clicky. Normal, needs grease and go with it?
Need metal gears?

 

[Reverendg]

I would defer to those who know more in that area. Gear looks ok though, maybe needs shimming?I am sure there are people with good answers here.
There are even smaller gears inside that “drum”. That’s the differential portion. Gotta figure out what’s clicking firstly.

 

[RCmc7]

Can I pair any motor, hobbywing for example, with this esc?

 

[Reverendg]

Brushless speed controls only work with brushless motors. And you need to match the amperage, within reasom.

 

[RCmc7]

Brushless speed controls only work with brushless motors. And you need to match the amperage, within reasom.

Yes I know that, but was trying to understand sensor less vs sensored. I couldnt find what the arrma blx esc was, but I think it is sensor-less.

I was trying to find a cheaper motor than the blx. So this is what I went with:

BLX 100esc and hobbywing quicrun 3660/3150kv.

Also got the spur assembly and pinion for jennysrc.

 

[305HemiGuy]

Yes I know that, but was trying to understand sensor less vs sensored. I couldnt find what the arrma blx esc was, but I think it is sensor-less.

I was trying to find a cheaper motor than the blx. So this is what I went with:

BLX 100esc and hobbywing quicrun 3660/3150kv.

Also got the spur assembly and pinion for jennysrc.

Yes, the BLX100 is sensorless. It will work great with 3150kv motor you picked out.

 

[RCmc7]

Yes, the BLX100 is sensorless. It will work great with 3150kv motor you picked out.

Ahh thank you for help! I did a lot of reading on motors I just hope I have all of the right pieces. So much to learn when you’re new at it.



If i understand things correctly, the new spur from a blx kit will be 57t vs the mega 91t. Do you think the diff gears will hold up for awhile being plastic? I think I will get the hot racing yokes and metal internals eventually.

 

[305HemiGuy]

Diff gears will be fine as long as you don't go beyond 3S power. Tons of us here have ditched the garbage brushed motors and upgraded to a brushless system without any issues. Just to confirm, you ordered the entire brushless 57t slipper clutch/spur assembly correct?

 

[RCmc7]

Diff gears will be fine as long as you don't go beyond 3S power. Tons of us here have ditched the garbage brushed motors and upgraded to a brushless system without any issues. Just to confirm, you ordered the entire brushless 57t slipper clutch/spur assembly correct?
View attachment 380082

Yes. I only have 1 pinion (20t) coming. Would like some different sizes to play with but haven’t bought those.

-motor mount w/motor heatsink & fan
-spur assembly and 20t .8mod 5mm
-center bearing w/driveshaft
-new diff case gaskets and 20k fluid?? Just a try at an improvement.

you ordered the entire brushless 57t slipper clutch/spur assembly correct?

This one

 

[305HemiGuy]

Yes. I only have 1 pinion (20t) coming. Would like some different sizes to play with but haven’t bought those.

-motor mount w/motor heatsink & fan
-spur assembly and 20t .8mod 5mm
-center bearing w/driveshaft
-new diff case gaskets and 20k fluid?? Just a try at an improvement.



This one
View attachment 380088

You should be good to go, looks like you ordered everything you need! Now I'm not telling you Not to change out the diff fluid, BUT I would get a feel for the truck and learn it in it's stock form before changing out diff fluids or doing any real serious modding. You'll see that it's a completely different animal on brushless power. You may like it just the way it is. But if you're somewhat familiar with that aspect of the hobby already, then by all means have at it and change out that diff fluid.

 

[RCmc7]

You should be good to go, looks like you ordered everything you need! Now I'm not telling you Not to change out the diff fluid, BUT I would get a feel for the truck and learn it in it's stock form before changing out diff fluids or doing any real serious modding. You'll see that it's a completely different animal on brushless power. You may like it just the way it is. But if you're somewhat familiar with that aspect of the hobby already, then by all means have at it and change out that diff fluid.

I will do that with the fluid and wait. Thanks. This is my sons truck so he wont know the difference but I tend to go overboard. I think its alll of the forum reading I have been doing. Im like, I need to do this and I need to do that. I appreciate your help and keeping the reins pulled back on me. I have been letting him drive the 3s senton while I try to get his fixed. He is getting good at driving.

 

[305HemiGuy]

I will do that with the fluid and wait. Thanks. This is my sons truck so he wont know the difference but I tend to go overboard. I think its alll of the forum reading I have been doing. Im like, I need to do this and I need to do that. I appreciate your help and keeping the reins pulled back on me. I have been letting him drive the 3s senton while I try to get his fixed. He is getting good at driving.

No problem man, that's what we're for brother! Sounds like the brushed motor crapping out may have been a blessing in disguise, once he gets a taste of that brushless power he's gonna be hooked, which it sounds like he already is lol.