How to flush out the Windscreen washer reservoir?

[pxrnm]

No, bleach will damage rubber and clear tubings. Peroxide is better but no point. Just use rainX additive first.

BTW rambohung, don't put in 1/2 a bottle of RainX solution. Start with 1/8 and then see if it is enough to get oily films off the windscreen. If it is not enough, spray out some water and then add more RainX and water again to mix.

actually I've done what rambohung did , that's because the rec. dosage is 1 Ltr = 30 ml of rainX. pretty much half the bottle was used (296ml for whole bottle)

should i spray it out and add in water instead?

will it damage anything if I don't do anything?