Dewalt drill

[jase158]

I am looking to get a little advice as pretty much going to get rid of it but want to learn about what I have found from it.
My dewalt drill was borrowed to my dad,

he rung me earlier and said it was smoking and really hot,

I have just been round there and the continuity test has brought up a reading of 112 and isn't beeping
( I have tested the voltage meter and this is working properly, beeping when touched together and I have pressed trigger on drill to get a circuit)
the volt test on the 18v batteries are showing 1 volt and 19.6 volts.

are both batteries broke?
why is the continuity so high?
any other advice from what I have found?

he tried both batteries in the drill and from what I can find on the internet I believe the drill has a loose cable inside or a broken motor, so believe he may have broke both batteries.

 

[MarkieSparkie]

I assume from the measurements that you have measured the battery terminal voltage with a high input impedance digital meter. One battery is likely to be charged (19.6V) and other deep discharged (1V), the deep discharged battery should be immediately put in the charger to see if it will accept a charge, and if so leave it charging/equalising in the charger for at least 24 hours for it to recover.
Your continuity measurement has been taken at the supply terminals to drill and will include not only the motor armature resistance, but also the brush contact resistances and motor speed control resistance so 112 Ohms is probably not unreasonable.
A likely reason for your drill getting really hot and smoking, is probably that it has been overloaded in the past and that has cooked the insulation of motor winding causing it to breakdown and resulted in shorted turns increasing the current drawn for the battery and increasing the dissipation of heat from the motor, speed control and battery. However, there other causes that might cause similar symptoms eg. gearbox failure, worn motor and/or gearbox bearings and extreme carbon brush wear
Do not subject the batteries to more abuse in the faulty drill, as it will quickly reduce their effective life.
If you are not familiar with power tool repairs, it is wise to take the drill and batteries to you local Dewalt service centre for assessment, and repair if you think the quoted cost is justified. If your drill is less than a year old and has not be abused it may be still under warranty, significantly reducing the cost of repair.
http://service.dewalt.co.uk/Support/AgentLocator/Default.aspx

 

[grantr37]

time to get a new drill, would sell the batteries and charger on e bay and get something for those, as somebody else will be able to use them, also reducing waste to recycling (or the tip) and bin the drill...you can get new parts for dewalt drills but for you it would be uneconomical, so its time for a new drill....

 

[Mark_Burgess]

Another thread in the wrong location!

I did see a few days back that screw fix had an offer on an 18v lithium Dewalt drill.

 

[richy3333]

I assume from the measurements that you have measured the battery terminal voltage with a high input impedance digital meter. One battery is likely to be charged (19.6V) and other deep discharged (1V), the deep discharged battery should be immediately put in the charger to see if it will accept a charge, and if so leave it charging/equalising in the charger for at least 24 hours for it to recover.
Your continuity measurement has been taken at the supply terminals to drill and will include not only the motor armature resistance, but also the brush contact resistances and motor speed control resistance so 112 Ohms is probably not unreasonable.
A likely reason for your drill getting really hot and smoking, is probably that it has been overloaded in the past and that has cooked the insulation of motor winding causing it to breakdown and resulted in shorted turns increasing the current drawn for the battery and increasing the dissipation of heat from the motor, speed control and battery. However, there other causes that might cause similar symptoms eg. gearbox failure, worn motor and/or gearbox bearings and extreme carbon brush wear
Do not subject the batteries to more abuse in the faulty drill, as it will quickly reduce their effective life.
If you are not familiar with power tool repairs, it is wise to take the drill and batteries to you local Dewalt service centre for assessment, and repair if you think the quoted cost is justified. If your drill is less than a year old and has not be abused it may be still under warranty, significantly reducing the cost of repair.
Service Agent Locator

Great, helpful post. Definitely worth a 'thanks' and I'm not even the OP