Clearing windshield from clogging constantly?
 

So on my 2005 ML350 the washer nozzles stop working all the time. I've pulled the main washer hose, backflushed it with compressed air and it keeps clogging.

When I look in the reservoir, I can see a bunch of crap in it. I've tried flushing it out with a hose over and over and the nozzles just get clogged again after a few seconds.
It looks like its leftover old blue washer fluid that has crystallized on the reservoir

I'm not sure if there is a better strategy here to clear it once and for all?

It's likely a mess of crystalized washer fluid and mineral deposits in the tank and in the lines causing repeated clogs. Take the bin out and wash it well, then flush a gallon of water or so through all the lines without the nozzles attached. That should flush the system out pretty well.

As long as there is a source of crystalline material, you're going to have repeated clogging of the washer jets.

I dont know is the newer MLs have it or not, but the grommets that hold the pump on can be swapped over to BMW parts, which have filters built into them, this prevents debris being sucked and impacted into the nozzles and hoses.

I also now use distilled or RO water to fill the washer tank and put some methanol in it to keep bacteria away and the filters have kept everything working so far.

however - I found a huge load of blue mineral deposit in the washer tank walls of my W210. - it also was missing an NLA part near the nozzles which I sourced from BMW too.

The deposits were from the leaking thermostat O rings in the coiled heating element.

It's a real pain to take the reservoir out as I have to remove the wheel, remove the fender liner etc...what a design....

I'll try flushing a few gallons through without the nozzles on and see if that helps. Filtered grommets if they would fit would be amazing!

Was going to suggest disconnecting the nozzles to blow any chunks out, but see that's been mentioned.

This is just one of the reasons I don't put anything in the windshield washer other than water. Don't need blue residue on the paint either. I've begun only using distilled water now that I no longer have a RO filter at my house.

The washer pumps on german cars are all similar (to a certain degree) - and all fit vertically into grommets - BMW sell those filtered grommets for about 5 or 10 dollars a piece. Real nice upgrade IMO.

remove wheel to remove washer tank? sounds like the germans are now taking lessons from the japanese. Nearly all japanese sedans from the 90s till today have theirs hidden behind the front bumper cavities.