Not really a necessary mod, and doesn’t affect performance, reliability or functionality. Just a little annoyance which I wanted to fix (again originally on my XP 70).
What you need:
1x Philips screwdrivers (size 0 or 1 [These sizes are guidelines only. A screwdriver at the correct size for the screw head, may not fit into the screw well.])
1x Thin flat plastic (from supermarket food boxes, etc. Be inventive! [Broken plastic ring-binder files are too thick. Look for something thinner than 0.5mm.])
1x Scissors or knife (strong enough to cut plastic)
First check whether the handle has lateral (side to side) or linear (back and forth) play.
Fix for Lateral Play
Remove the screws from, and open up, the pump handle. Take off the two halves of the pump handle, leaving the pump rod.
Look at the pump rod locating peg(s) inside the pump handle, and cut a/some piece(s) of plastic to fit in the recess for the pump rod (I needed two). You may need more/less depending on the blaster and how thick the plastic is [I was using 0.25mm thick plastic]). Make sure it has pieces which go around the locating pegs.
Place the first piece into one of the pump handle halves. Close the handle up and test for lateral play in the handle.
Open the handle up and add more shims as necessary (try to keep the number on each side of the pump rod as evenly distributed as possible).
Once happy close the handle up.
For Linear Play
(My Colossus didn’t have any linear play, so the following pics are of an XP70 pump handle for demonstration purposes.)
Open the pump handle as per the fix for lateral play.
(note the gap between the pump rod locating peg and the locating hole)
Look at the pump rod locating peg(s) inside the pump handle and cut a piece of plastic to fit tightly around the locating peg.
The plastic piece should not protrude through the locating hole(s) in the pump rod by more than 0.5mm.
Close the handle and check for linear play. Adjust the shim as necessary.
Once happy close the handle up. ~Andrew