Screen wash

[Petrol Pete]

Algae in the washer bottle | Parts, Maintenance & Servicing

Advice please. Mrs jdrrco's lovely W202 has only done 45k miles in 22 years. Most things on it are like new, but the windscreen washers lack enthusiasm. Topping up the washer bottle yesterday, I saw a fair bit of gunky algae which has, no doubt, made its way up the tubes and is contributing...

forums.mbclub.co.uk

We did this the other day.....

 

[Rubyred]

Halfords blue screenwash for me also. Have used it for many years with no blockage problems.
Just people’s choices I suppose.

 

[tonysmb]

I've looked a bit deeper into this recently, using the product datasheets, if nothing else to satisfy my own curiosity.

The MB one has different ingredients to most others, namely ethanol, propan-2-ol (isopropyl alcohol/rubbing alcohol) & butanone (MEK methyl ethyl ketone). The only other brand I could find with the same constituents was the Volvo-branded screenwash (very slight percentage differences, not identical but probably effectively virtually the same). Shell Essentials Winter has similar main products but also ethanediol (ethylene glycol), however, couldn't find it in the UK.

Most others contain methanol, some contain butyly glycol, others ethylene glycol, ammonia, propylene glycol etc.etc.. (Prestone -10 contains methanol and ammonia). Sonax and Wurth different again.

VW concentrate screenwash contains sodium hydroxide. Others looked at included Car Plan (TetroSyl), Comma Xtreme, Autoglym (gets good reviews), Unipart, Eurol, Halfords.

There was one study (USA IIRC) which showed methanol is not compatible with polycarbonate headlight covers, however, I didn't check concentrations etc. etc.. Other sources state it should be okay

Performance re freezing etc varies considerably. Some cars rely on correct 'conductivity' for screenwash sensors to work. Having seen the variations in 'ingredients', I'm not surprised that mixing some variations together might cause a chemical reaction and change in viscosity etc.

Having spent a few hours reading up on it, I ordered some more MB screenwash, even though I already have about 15 litres of other screenwashes in the garage.

It seems that screenwash is becoming like oil with loads of different products; it used to be simple.

Each to their own but at least it might help explain some of the differences.

 

[Wearsthefoxhat]

I have used MB winter or summer fit for many years. No algae, squeeks or problems.