Help! Hot motor

laramie187

New member
I built an alpha...I put in a 2205 2300kv ft motor, ft 20amp esc, and a 4s 850mah battery....the motor gets so hot after a few seconds of flight...meaning it will burn you if you touch it...then tried the 1806 2280 with same esc and a 3s 850mah battery....and it also got extremely hot after a few seconds...yes I have the pusher prop on.......which way is the motor suppose to turn...ccw or cw...I thought cause of the pusher prop it would go clockwise...even if I had rotation wrong and prop on backwards I wouldn't think it would get this hot....it actually will shut down it gets so hot

My goal is to make this thing extremely fast...so if you have a recommended motor that would be great too
 

JasonK

Participation Award Recipient
  1. What prop are you using? it sounds like you have it over propped, the A pack motor can run up to about a 6x3 prop on 3s, if you go up much in prop from that it will overhead.
  2. Number on the prop should face forward, then the motor should be spinning in the direction that causes it to create forward thrust. (there are CW and CCW props and depending on which you would switch the direction of the motor)
  3. Do you already know how to fly? you don't want to start with 'extremely fast' until you have 'just flying' under your belt
 

laramie187

New member
  1. What prop are you using? it sounds like you have it over propped, the A pack motor can run up to about a 6x3 prop on 3s, if you go up much in prop from that it will overhead.
  2. Number on the prop should face forward, then the motor should be spinning in the direction that causes it to create forward thrust. (there are CW and CCW props and depending on which you would switch the direction of the motor)
  3. Do you already know how to fly? you don't want to start with 'extremely fast' until you have 'just flying' under your belt
They are 6x45 ccw.....I only put the a pack motor on for a function test....I want to run the f pack motor but it melted that motor as it got way too hot
 

laramie187

New member
They are 6x45 ccw.....I only put the a pack motor on for a function test....I want to run the f pack motor but it melted that motor as it got way too hot
I'm good on the flying department...ive just never set up a pusher style plane and with it getting so hot I just am not sure of anything now
 

JasonK

Participation Award Recipient
They are 6x45 ccw.....I only put the a pack motor on for a function test....I want to run the f pack motor but it melted that motor as it got way too hot

6x4.5 got my A pack motors very hot on 3s.

Try the F pack motor with the 3s battery with that prop and see how you are.
 

JasonK

Participation Award Recipient
also make sure your motor screws aren't touching the windings in your motor... that causes problems
 

JasonK

Participation Award Recipient
I already tried that...doesn't matter...after 3 seconds you can't touch the motor
that should be fine, check your mounting, I suspect that you have shorted out your windings with your mounting screws then. or have something causing binding in the motor... or some other mechanical issue.

F pack with that prop and the plane should be feeling like it is going to pull itself out of your hands.
 

Keno

Well-known member
One thing you might check is for binding of the motor saft on the firewall. This can happen when you tighen the mounting screws or the saft moves forward at speed. I believe you said it was a pusher. I see comments on prop loading good advice to follow.
 

skymaster

Elite member
Do you have a spare esc. it might be your esc, wile back i bought a cheap combo and it would do the same thing you are describing the esc had a heat sink but the thermal paste was all over the place and started smoking thing died. got me a new esc and the motor worked flawlessly.
 

ProfessorFate

Active member
Look at innov8tivedesigns.com motors, see their charts. Figuring 2205 is stator size seems a bit small.

Lucian at innov8tivedesigns.com recommends 100w per #.

I wound this 3508q 10t 20ga hpdlrk wye 22a limit using a quieter 8x6. Tested 830kv 26.5a WOT on 4s life, should be fine on lighter 3s lipos est 2.5# or more
 

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quorneng

Master member
laramie187
A simple test - take the prop off and run the motor.
If it still gets too hot to touch after a few seconds then the motor is scrap.
If it doesn't then use a smaller prop like a 6x3 as advised.
A word of warning. If the motor has really got that hot it is likely damaged anyway and should be replaced.

Now if you had a Watt meter connected when you first tested the motor you could see instantly that it was drawing too many amps and stopped before you damaged either the motor, ESC or the battery.
 

will.fred.tx

New member
I beefed up the power on mine & it screams! No problems and getting 86 mph calculated speed in level flight at full power.

FT Radial 2205 2300kV motor

50 amp ESC

850 mA 4s 100C lipo.

6x4.5 e prop (2 blade)

Added a little weight to tail to balance out the 4S pack.

I would not recommend and higher propeller pitch or a 3 blade prop as I feel this setup is at the max of the envelope without burning up the motor.

I'll paste the YouTube link for the Maiden flight below.