Windshield washing fluid

So often do you change it?

You don’t ‘‘change’’ it, you add more when it gets low.
Your unknow vehicle could have a level sensor …or …best of all, look and see.
If the cap is not well marked , your owner’s manual will tell you where that is.
At any parts store you can buy pre-mixed or concentrate.

most oil change places top it off along with coolant and brake fluid included in the deal. You may not even know it if you are diligant about oil changes and never even notice that you’ve been low and now it’s full.

Sometimes…
sometimes, people will change from summer mix to winter. They even make an ice melting washer fluid .
But most times just putting in enough winter mix is good enough to not need to change it at all.

Hopefully this is not a serious question.
And, hopefully, some chain auto repair franchise is not resorting to extorting money from naïve folks for “changing” their WW fluid.

I never change my washer fluid, but, due to depleting it as a result of normal/regular use of the windshield washers, I suppose that I refill the washer fluid reservoir a few times per year.

You’ve never seen alcohol evaporate?

I use mine fast enough that evaporation isn’t an issue. Are you worried about it freezing this winter? Just fill it up in November.

Of course I have seen alcohol evaporate–albeit very slowly, due to the reservoir being well-sealed-- and that reality, coupled with the use of the washers, is why I refill the reservoir a few times per year.

Your question was about, “changing”, the washer fluid, and–IMHO–that can mean only two things:

Draining the reservoir & refilling it
or
Changing from a summer-type fluid to a winter-type fluid

Can you clarify which of these you are asking about?

The only time I ever replaced my washer fluid was when my oldest son added antifreeze to the washer fluid.

I’ve done that. It’s Sliming.

Whenever it needs to be changed. It’s essentially a jug of water sitting around getting slimy. On my personal cars it turns into smelly pond scum faster than it gets used. Maybe it’s the climate here, but half of the time when a car comes to me with inop washers the pump is trying but either the inlet screen or nozzles is plugged with muck.

On a related note, why are washer tanks getting so big? Some cars hold over a gallon of fluid. I haven’t used that much in my life.

On a related note, why are washer tanks getting so big? Some cars hold over a gallon of fluid.
@asemaster–I like these large reservoirs. I can pour in a whole gallon of washer fluid at a time and not have to store a half used jug. I seem to go through a gallon of fluid about every 6 months in our vehicles.
Years ago, I was returning from my inlaws back to graduate school. The roads were covered with slush and I ran out of fluid. The Rambler I owned had a plastic bag that probably held a quart. When I stopped for gas, the attendant who pumped the gas asked if I wanted the windshield washer reservoir filled for $1. I gladly paid the dollar. The gas stations attendants were offering this to all the motorists who stopped. I thought that this service was great–the station was making a well deserved profit and it was helpful to the motorists. I probably wouldn’t have needed the service had the car had a larger reservoir.

If I had a ‘slimed’ reservoir, I’d stick a hose in it, flush it out, dump some hydrogen peroxide in it, flush that out, then siphon out the water and fill it back up. One disadvantage to these big reservoirs is that they’re hard to remove in my cars, so I wouldn’t be able to easily do this off the car.

And I remember having problem with ‘RainX’ fluid a few years back - I was about to fill my tank and noticed junk floating around in an unopened bottle (don’t know how long I had it, less than a year I think).

I use the washers a lot, go through about a gallon a year between the two cars.

On a related note, why are washer tanks getting so big? Some cars hold over a gallon of fluid. @asemaster--I like these large reservoirs.

So do I. Living in the North East…I can go through a gallon of washer fluid in just a couple of weeks. Try driving after it snowed right after the plows got out. The roads are sloshy…and all the cars/trucks in front of you are spraying onto your windshield. Wipers alone won’t get it clean.

Well, I doubt anyone running standard blue wiper fluid has to worry about “slime”: not a lot can grow in a methanol solution.

For even volatile methanol to evap up and out of the washer tank, I think the cap would have to be loose/missing, or the stuff would have to be in there for YEARS.

Fluid comes in gallons; the reservoir should naturally be the same size. Seems like most are about ~3 qt, which means I wind up wasting money (not worthwhile to store 1qt due to PITA exceeding purchase cost). It’s “12 hotdogs per/8 buns per” all over again.

“The Rambler I owned had a plastic bag that probably held a quart.”

That brings back memories, Triedaq!
My father’s '66 Ford Galaxie 500 (IIRC, 1966 was the first year for Federally-mandated windshield washers) also had a plastic bag hanging in the engine compartment that held–at most–1 qt. On a winter day with lots of salt on the roads, it was possible for me to use up that quantity of WW fluid in just a couple of hours, due to the small size of the reservoir and the fact that the nozzles of those days were not very precise, and tended to just gush fluid.

I also appreciate the very large WW fluid reservoirs on modern cars, and that allows me to go for–maybe a few weeks—during a hard winter before I refill it. Even in the summer, bugs on the windshield cause me to use the fluid often enough that I can’t imagine anyone leaving the fluid in there long enough to develop “slime”.

You see, evaporated alcohol in WW fluid gets you Slimed.

I need to get a sp gravity thingy to test for alcohol level. :<}}

Folks would be surprised the conditions in which bacteria can grow. They’re hardy little critters!

My 1954 Buick had a 1 quart glass reservoir under the hood. The fluid was pumped out by engine vacuum. We used water in the summer and there was a windshield washer antifreeze to add in the winter to the water in the windshield washer reservoir. When the premixed windshield washer fluid came along in gallon jugs, I thought that was great.

Idea #349.

Recover the condensate from the air conditioner to maintain WW fluid level. All you would need is a float switch, a small pump, small reservoir, and hose. If you need more fluid, get more clowns.

I breath more often than use the WW. :<}}

“All you would need is a float switch…”

How about just locate the WW reservoir lower than the condensate drain outlet, and let it drain in?

@longprime and @circuitsmith
This may be a good use for the air conditioner condensate, but some provision must be made to add alcohol to the condensate in the winter to keep the washer fluid from freezing. Also, the alcohol or whatever added to the premix fluid helps in cleaning the windshield. In addition to the pump that longprime suggests, a metering device would have to be added and controlled by a microprocessor to add the correct amount of washer fluid antifreeze. This takes us back to the 1950s before the days of premix fluid except that the systems in the car do this for us. Personally, I think this is a rather complex solution to get out of purchasing premix washer fluid which is often on sale for less than $1 a gallon and it takes less than a minute to pour in the fluid.