Windshield washer questions: check valves & heaters.

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BrianK
Posts: 277
Joined: Aug 01, 2012
Location: Los Angeles

Windshield washer questions: check valves & heaters.

Post by BrianK »

While waiting for parts to arrive yesterday, I had a look at my non-working windshield washers.

According to the Bentley, I tested the washer motor at the relay box. It works. It seems to be spraying water out of the first check valve, however. This is true even when there is no line on the outlet.

Image

I'm guessing the check valve is bad... either that or I don't understand what it's supposed to be doing. I've not seen one of these check valves for sale on Pelican or Autohaus (and haven't managed to find the correct diagram on realoem to find a part number). Does every car have them? Is it necessary? What purpose does it serve? Can I remove it? If not, where would I get one? For the record, this valve sits just behind the strut tower. It is between the reservoir and the T fitting. I'm guessing it keeps fluid in the line so you get instant washing, but rather than guess, I'm asking. :)

I also noticed that there are wires running to the nozzles themselves. I'm guessing this is for the heated washer option.
Assuming the nozzles are blocked (which hasn't been tested yet), can I replace the heated nozzles with the non-heated? Do they have the same mount? Does anyone actually use or care whether or not they have heated washer nozzles?
TheLazyDog
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Joined: Oct 26, 2011
Location: Elgin, Illinois
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Re: Windshield washer questions: check valves & heaters.

Post by TheLazyDog »

Does every car have them?
No, mine doesn't. I don't think the Bugatti Veyron does either, but don't quote me on that.

Is it necessary?
For the washer system to function as intended, yes.

Can I remove it?
If I were you, I would buy new hose, get rid of those valves and use the vavled "T" fitting-- PN 61661374978.

If not, where would I get one?
No idea. I cannot find them either. I think they are obsolete.

What purpose does it serve? I'm guessing it keeps fluid in the line so you get instant washing...
You are right.

I also noticed that there are wires running to the nozzles themselves. I'm guessing this is for the heated washer option.
You are correct.

Assuming the nozzles are blocked (which hasn't been tested yet), can I replace the heated nozzles with the non-heated?
Yes. Do check them before you replace them; guitar string works nicely for that, should even free them up.

Do they have the same mount?
Yes. If I recall correctly, there is no "mount". If you remove the the spray nozzles, you will have to secure them back with an adhesive. I used silicone window sealant I bought at Home Depot. Specifically, this one from GE:
Image
Wrapped a 20lb. dumbbell in a towel, layed one side on the spray nozzle, and left it to cure for a week (not that it needs that long).

Does anyone actually use or care whether or not they have heated washer nozzles?
Maybe the Alaskans; it doesn't hurt to have them heated, they will function like non-heated ones if the element is broken.
BrianK
Posts: 277
Joined: Aug 01, 2012
Location: Los Angeles

Post by BrianK »

A very thoughtful response. Exactly what I needed.

Much appreciated.

:up:
tn535i
Posts: 5590
Joined: Jul 14, 2006
Location: Middle Tennessee

Post by tn535i »

From my experience...

Agree... get the new tee with built in check valve. It's the only thing that really seems to work right and I think it is even designed to help balance the flow left to right.

From memory the nozzles snap into place unless the little protrusions in the plastic are broken or worn away. Not too hard to remove the from the hood and no glue should be needed to hold them back in place.

If you clear it with a wire or guitar string it may just push junk down in there that will quickly plug it again. Take them out and soak them in vinegar or such to break down the hard deposits. And use a length of hose to suck fluid up into the nozzle. Vinegar won't kill you if you get a taste of it.

Unplug the heater unless you really need it. The problem with the heater is it will just accelerate the formation of deposits. At least that's been my experience on my 6er (w/ heaters) with realitively low miles while the other cars (w/out) with high miles not nearly as bad to plug up. And it can leak fluid through the heater part if the little gasket goes bad. I looked into these once and I think they were discontinued. Probably one of those things that sounded like a good idea but proved to be the source of more problems than the rare problem it solved.

You also know you can use a safety pin or stiff wire to aim the nozzles once they are all cleaned up.

Yes, consider new (unheated) nozzles which I think are $10-11.
TheLazyDog
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Joined: Oct 26, 2011
Location: Elgin, Illinois
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Post by TheLazyDog »

tn535i wrote:From my experience...

Agree... get the new tee with built in check valve. It's the only thing that really seems to work right and I think it is even designed to help balance the flow left to right.

From memory the nozzles snap into place unless the little protrusions in the plastic are broken or worn away. Not too hard to remove the from the hood and no glue should be needed to hold them back in place.

If you clear it with a wire or guitar string it may just push junk down in there that will quickly plug it again. Take them out and soak them in vinegar or such to break down the hard deposits. And use a length of hose to suck fluid up into the nozzle. Vinegar won't kill you if you get a taste of it.

Unplug the heater unless you really need it. The problem with the heater is it will just accelerate the formation of deposits. At least that's been my experience on my 6er (w/ heaters) with realitively low miles while the other cars (w/out) with high miles not nearly as bad to plug up. And it can leak fluid through the heater part if the little gasket goes bad. I looked into these once and I think they were discontinued. Probably one of those things that sounded like a good idea but proved to be the source of more problems than the rare problem it solved.

You also know you can use a safety pin or stiff wire to aim the nozzles once they are all cleaned up.

Yes, consider new (unheated) nozzles which I think are $10-11.
Awesome tips. I'm personally not convinced about the heated nozzles being a bad thing, though.

And I guess my "protrusions" must have been broken away.


Maybe it it worth mentioning you can "make" your own washer fluid. I mix 1z's Kristall Klar concentrate with distilled water. They claim it prevents mineral build up, I haven't used it long enought to say for sure myself.
BRRV wrote:...Next, avoid, at all costs, commercial methanol based washer fluid. It's mixed with hard water, full of crud and minerals, and it will clog your nozzles. See that white stuff?

I use a concentrate I buy from 1Z (Einszett), distilled water and in the winter time 90% IP alcohol added as an antifreeze. You can also buy an alcohol-based washer antifreeze from 1Z, but it's expensive. Since doing this, my nozzles never freeze, gum up, or stop working. They do, however, continue to need slight re-adjusting every month or so.
I have gone the route of adding isopropyl alcohol as well, but I would not recommend it. Not isopropyl, anyway. It is an oil solvent and, I suspect, the reason the rubber on my wipers dryed out very quickly.
wkohler wrote:I use a small paperclip bent into shape. I run it in each nozzle, several times, then try the switch. It usually works. I also always do this with the hood closed. Shawn D. uses a piece of acetylene torch cleaning rod which fits nicely in the nozzles.

For washer fluid, I use a P21S concentrate mixed with distilled water. Works indubitably well.
^The first bit is about cleaning the nozzles. Link to P21S "windshield wash booster".
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