Winter project - Udo rigger

This time of year is good for repairing things that you just haven't
got around to. Amongst my other winter projects is refurbishing an
older Udo rigger.
The Bilstein screw jack was not working smoothly, and produced
clicks while raising or lowering. When it clicked, the jack was not
raising or lowering. Sounds terminal, but it isn't necessarily.
If you have a similar problem with a screw jack, remove it (on the
Udo rigger, 3 bolts) and clean the threads. I found that there were
pieces of gravel stuck in the grease in the threads of the screw jack.
These forced the spring-loaded teeth of the carriage which rides on
the screw to come out of the threads and click back in. Cleaning the
threads out with a screwdriver eliminated the gravel. A little WD40
along the screw and the whole thing runs smoothly. Using heavy grease
which will pick up dirt is a recipe for more trouble.
Takes half an hour on a rainy day. (unlikely to happen on a sunny
day)
Jim