B44.3 INTERMITTENT LOSS OF DRIVE

[milesallen]

B44.3 had a few issues today, after jumps with either a hard or soft landing the car lost all drive, spin the wheels manually then its away again.

All a bit odd, new motor in it (so could be that) but maybe the drive train shimming diffs etc, car runs free etc.

Anyone any ideas?

[stegger]

Could well be the motor and check your sensor cable ! sounds like a bad phase. With you manually turning the transmission you are also turning the motor. HTH

[Big G]

a phase is down on the speedo. I had the same thing. Won't start from standstill, but if you give it a push it'll go.

[milesallen]

Thanks guys - its a new speedo and motor - it works fine for 99.9% of a heat or all of it, will go from standstill at the start etc and most of the heat and doesn't fail all the time just after a jump and as ever not every time.

Just had the gear boxes apart for a look and the centre diff etc (deep joy), all looks well so maybe not mechanical.

I'll try a different motor see what happens and move onto the speedo etc.

Cheers

[K-Brewer]

It will be something electrical, check sensor wire but what speedo an motor are u using?

[Noob]

New or old sensor wire, they are prone to break also check the solder joints for cracks

[zoaman]

I WOULD DE SOLDER THE MOTOR AND ESC AND THEN RESOLDER.THIS WILL ELEIMINATE A BAD JOINT .THIS WONT COST ANY THING.I SAY THIS AS YOU FIND ITS AFTER A JUMP(HEAVY LANDING WILL CAUSE THE CABLES TO LOOSEN TEMPARARILY).THEN IF NOT TRY AS OTHER HAVE SAID WITH SENSOR CABLE.BUT NORMALLY WHEN YOU PUSH THE CAR IT TURNS THE MOTOR PASSED THE DOWND PHASE AND RESTARTING THE MOTOR.THENTHE MOMENTUM KEEPS IT GOING.

[discostu]

It's more likely a sensor issue in the motor or esc assuming you have changed the sensor wire rather than a phase down

The hall sensors in the back of the motor tells the esc the position of the magnet so the esc knows what phase or pair of phases to fire and at what point the overlap take place to increase timing etc

If a complete phase had failed the motor would feel very odd.

[Noob]

And probably run hotter,you can eliminate a bad phase by disconnecting one wire at a time and manually turning with a bit of throttle until you find a pair that won't work then and it's obvious which one it is eventually, it will only really help you to check that phases connection in the end.

[Danny Harrison]

This could also be a wire pressing on the set up button on the esc. something to check

[milesallen]

Cheers

I'll check the sensor wiring etc, the motor was strong and no over heating etc. maybe a sensor cable i've got a few spare ones will see what happens,

[stegger]

Have you got this sorted fella ?

[milesallen]

I think so, I've changed the sensor wire, all seems fine, can't seem to replicate the fault, the soldering to the esc & motor is 100% so will see how it goes next time out.

The car will run with out without a sensor wire, so would seem odd if that had gone faulty but it was a new one might have been a dry joint who knows..........

I did find that a motor screw was missing so replaced that too (nipped up a bit tighter - always worried about stripping motor cans) maybe that had something to do with it but the mesh was still bang on.

Anyway thanks to everyone - will run it again on Sunday see what gives.
If it packs up agin I'll sling it in the bin. LOL!