Can somebody help me with this problem?

my wipers stop  after one minute or two of functionng.No way to get them to work unless I switch them off and wait some time before retrying.-

.

So I thought the brushes of the motor were at fault, and I disassembled the motor.  : - ))

Now, inside it everything is clean, the brushes are in good shape and at half their size.

After that,  I got two problems to solve:   :- (

1) what could be the possible causes that stopped the motor from working;

2) How do I get the brushes back on the rotor, since they are at the bottom

of the cover with the fields, the rotor is square against the brushes sides and

of course the brushes won't jump that step by themselves ? Is there some special tool to buy or to make?

 I thank you for any hint and suggestion.