# Motor overheating/smoking



## durnells (Jul 25, 2009)

My daugher and I just finished a 120volt volkswagen rabbit pickup conversion for her. The motor is getting very hot after only a couple of miles and no real hills. We pretty much copied the wiring from Michael Browns "Convert it" book.
Batts are 20ea 6 volt US 2200 lead acid wet cells, pack is fully charged 1.26 sp Gr. each cell, pack voltage 130 volts.
Controller is Curtis 1231C.
Motor is from Wilderness electric vehicle "kit" 6-3/4" O.D. class H, Model #107-015-0004 Don't have any real specs on the motor, is it too small for our application? How hot can a motor get? we probably need to get a motor temp sensor / Gauge.
Ammeter is in series with the pack and reads up to 300 amps when starting out in second and then drops to roughly 100 when crusing between 20 to 30 mph in second gear. Would moving the volt and ammeter to measure motor voltage and current give us any better information?


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## Tesseract (Sep 27, 2008)

durnells said:


> My daugher and I just finished a 120volt volkswagen rabbit pickup conversion for her.
> ...
> Batts are 20ea 6 volt US 2200 lead acid wet cells
> ...
> ...


Yes, you want to know motor current. That is what determines how hot the motor gets. Battery current determines your range (which is not trivial, either  )

6.75" is too small for this application, given the weight of the vehicle and what was added in batteries (yes, you lost the engine weight, but that doesn't make up for what you added in lead). 

I wouldn't think the Curtis could deliver enough amps to overheat this motor, though - Class H insulation is rated for 180C and the Curtis 1231C seems to settle down to around 250A on the motor side once it has been in use for a few minutes.


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## durnells (Jul 25, 2009)

Turns out motor is D&D ES31B which should be ok for the VW pickup. we need to have it weighed. We didn't know that electric motors had a break in period for the brushes to fit to the commutator. The guy at Wilderness EV says new motor efficiency can be down around 65% untill brushes wear in and then efficiency should be around 80%. So we will drive it easy for first 50 mi or so. Also had a bad wheel bearing which didn't help. Hopefully these ad up to our new motor overheating issues.


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## neanderthal (Jul 24, 2008)

I hope that fixes it Keep us updated


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