On 22/04/2018 12:22, Bert Coules wrote:
I was using my fairly elderly low-end Ferm rotary hammer to do some
heavy-duty chiseling and the tool fell out.Â* When I tried to replace it,
I discovered that the rubber sleeve would no longer pull back.

Removing the sleeve and the small additional grommet-type thing that
sits in front of it didn't leave me any wiser: the shaft of the chuck
still moves in and out, but even at its extreme inward position the tool
doesn't lock.

Looking into the chuck I can see the lengthways raised strips which
guide the tool in, but no visible locking mechanism - which I've
discovered from an online search should be a ball bearing.

Does this mean that the entire chuck has to be replaced?Â* Another quick
search hasn't thrown up a source, but even if it had I suspect that it
might be almost as expensive, and a great deal easier, simply to replace
the whole thing.Â* Am I right?Â* Comparable budget models seem to be
around for £50 or so.

Many thanks.

On my Makita you could just swap the ball bearing.

--
Adam