Hi
I have a couple of SDS drills which both have the same problem:-The hammer action has virtually disappeared.
Electrically both drills are fine.
To start, the drills are of the pneumatic hammer action with the motor vertical beneath the drill, made probably in China and normally costing between £20 and £40.
I have dismantled the drills and can find nothing obviously wrong and have reassembled using new 'O' rings but when started there is very little hammer action. I must be failing to do something which makes then work.
The piston moves smoothly in the cylinder as does the hammer, and the rod transmitting the hammer blow to the chuck also moves smoothly.
Can anyone offer any advice ?
regards
phil

I think the hammer is, in part a hydraulic action using grease. There is usually a grease chamber which has to be refilled on a fairly regular basis to maintain the hammer action.

_________________
Mike

hi mike
The grease pot is full and I have tried wiping the piston and hammer clean and trying it and with liberal quantities of grease on both parts. Does not seem to make any difference.
Thank you for your interest.
regards
phil