Windscreen wiper arm

[Kevbo]

My driverside wiper seems to have developed a mind of its own, it'll make a sweep but then flops down as though the splines are worn and not engaging to drive the wiper. However the splined piece seems to be loose on the wiper spindle, I can turn it easily. Any thoughts on a repair? I'd seen something that suggested drilling through the splined piece and spindle and inserting a suitable pin. Anyone done this? Alternative I guess is to buy a new rack.

[lowact]

I’ve never had this problem. Replacing the wiper mechanism requires major dismantling including wiring looms so case for trying anything else first is obvious. If it does not work, it was no good anyway?

Drilling for a roll-pin-would be tricky imo.
Through from the side (cross-pin) may be too difficult. The splined head is die-cast, the shaft is steel. The die case would need to be thick enough, so the end of the roll-pin could be deeper than the spline and still hold, dunno if it is. The drill-bit would need to hit the shaft centreline exactly square-on, else it would just run sideways tearing through the die-cast. Maybe use an old wiper-arm, with a pre-drilled pilot hole, as a guide? Start with a smaller drill-bit, then ream it out to pin size with a larger one. High speed 1000-1500 rpm. Hand-held = high risk of breaking the bit if it is too small …

Maybe better/easier to put a roll-pin in the end of the shaft, i.e. axially. I’m guessing the end of the shaft is flat, if so, the drill bit would be less likely to run sideways. The hole would need to be totally into the shaft, cannot be into the die-cast (spline) otherwise it would run sideways. If the bit breaks off in the process, no worries just grind it flush and call it the pin?

Maybe drilling a hole in the end, initially just far enough to pressure-inject some suitable glue might be the easiest first effort? Getting the glue in there would be the problem, you might need to screw in some sort of tiny feed tube....

Whatever, have fun and protect yr paint…

[Kevbo]

Thanks for the reply Colin. As you say not so easy to pin from the side. I did punch three small indentations on the top of the spindle in the hope that it might create sufficient interference to hold the spindle bush, no luck though.