Need Help, rotor won't spin up

oldmanflyer · Posted: Thu Apr 29, 2010 10:28 pm Post subject: Need Help, rotor won't spin up

Hey guy's I need help,
on battery pack #4 I did a dump mistake. I never change the thorttle hold switch to 0%, it was set at 50%. I was doing Radds course battery #4, and when I went to put the heli back in the box I hit the thorttle hold switch accidentally. And you all know what happen then.Well now the rotor head will not spin up with the motor, it will spin a little. What can be the cause the this problem. All suggestion will be appreciated.

tombo242 · Posted: Thu Apr 29, 2010 10:49 pm Post subject:

Hi oldmanflyer,

You don't say what T-rex model it is, but possible causes, not in any particular order, are:-

Gears slipping.

Jesus bolt (or two) snapped. Quite likely if the motor is spinning normally.

Damage to the ESC.

Damage to the motor.

Battery current over its max' ruining the battery. Not too likely that one.

Idea

Let me know if after a check it's none of these and I'll think again.

oldmanflyer · Posted: Fri Apr 30, 2010 3:37 am Post subject:

Sorry about that, it is a T-Rex 450 SE, the motor will spin-up fine. I don't think it is the ESC/ICE 50. I'll have to check the jesus bolt.

tombo242 · Posted: Fri Apr 30, 2010 4:54 am Post subject:

Sure oldmanflyer,

If the motor's good the the Jesus bolts (check both head and gear bolts) are prime suspects. One is likely to be sheared, but even if the other is only slightly damaged then it is worth while replacing it.

oldmanflyer · Posted: Fri Apr 30, 2010 5:24 am Post subject:

Thanks Tombo242, as soon as I can I'll do that.

oldmanflyer · Posted: Fri Apr 30, 2010 5:33 am Post subject:

Tombo242, I just checked it out and quest what it was. The pinion set screw was lose.

tombo242 · Posted: Fri Apr 30, 2010 1:59 pm Post subject:

Thanks for letting me know Oldmanflyer, looks like my very first hint was right! Very Happy

(It's not always Sad

.)