Having used my Mk7 Fiesta ST so little over lockdown I discovered yesterday when i used the washers that the fluid now stinks 😞

This is a reasonably new development, probably due to the recent hot weather, but the washer fluid probably hasn't been changed since before lockdown.

Is there any sort of drain plug at the bottom of the washer bottle I can use or is it a case of detaching the hoses from the jets and draining that way using the pump? Any suggestions for the best way to flush it out or clean it?

The washer pumps connected to the tank usually can be removed when you get access to the bottom of it, and then just drain out the water into a bucket. It's the black part with the motor attached which you can just pull out to expose the drainage hole.You could put a hose into the other end and just flush it out with clean water to get rid of the gunk and debris.

Once it's drained, fill it with clean water or washer fluid.  The pump I believe also has its own filter which should be cleaned too.

My car actually has a blockage somewhere meaning I don't get any fluid out the washers so awaiting a service appt, but if I knew how I could access the tank myself from the bottom that's probably what I would start doing first and literally clean out the whole tank lol 😅

Have you tried smelling if it's the fluid by opening and sniffing around the washer fluid filler cap? The alcohol and chemicals in it, I'm surprised anything would be able to grow, unless it was considerably diluted.

I wonder, if it might just be a smell in the pipes coming from the tank to the jets.

Yes it could just be the fluid going off rather than stuff growing, although I'm not quite sure what concentration I currently have in there. It also might have got a bit low which wouldn't help.

Anyway, this morning I detached the bonnet hose and ran it to a bucket down beside the front wheel and flushed the bottle through with a lot of clean water from the garden hose. Then I put citrus degreaser in it and left it for an hour. I'm about to go out and flush it all through with lots more clean water then fill it with neat screenwash (assuming it doesn't smell anymore)...

Try not to breathe it in unless you want legionnaires disease...  

 

22 minutes ago, TomsFocus said:

Try not to breathe it in unless you want legionnaires disease...  

 

Well the smell was all blown in with the aircon so it's a bit late for that!

Having run it through, the smell has gone and the water was coming out clean.

It's now brimmed with neat screenwash so fingers crossed its sorted 

15 minutes ago, TimST2 said:

Well the smell was all blown in with the aircon so it's a bit late for that!

Oh dear!  Well, if you subsequently get a fever and breathing difficulties, at least you now have the fun game of trying to work out whether it's Legionairres or Covid19... 

Seriously though, it's another droplet based infection, it shouldn't get through the pollen filter!