Why not just one check valve at the windshield washer pump?

[snbush67]

Originally Posted by cabmando

There I was, all excited about getting my new washer pump. I installed it, put 1 gallon of fluid in the tank, applied power to the pump, pump makes a sound, fluid flows from the nozzles at the windshield.... and from the bottom of my new pump

Weird, time to move this thread to PARF. Is a reverse gender pump?

[cabmandone]

I don't know about reverse gender but I did consider it might be Covid positive with it spewing fluid from the bottom. I dropped a hydroxychloroquine tablet into the washer tank to see if it clears up.

[hcoles]

subscribed - great timing that this thread got started. I took my tank out and cleaned it - haven't tried the whole system. I'll probably use distilled water to start with.

[GH85Carrera]

Distilled water will not hurt, but way over thinking it. It is almost all plastic, so no corrosion to worry about, and the system is for sure not close to needing distilled water. Tap water is fine unless it is super hard water. You really should put some of the blue washer fluid in it even if you have no intention of ever getting into an area below freezing. Water, even distilled water can grow mold and gunk pretty fast, even without light.

[Coblue]

Pretty sure the check valves are there in the nozzles to prevent the nozzles from sucking in air or other nasty things. They also keep fluid in the hose, so the pump doesn't have to work as hard. Also, with no check valve, your driver side nozzle will start squirting long before your passenger side does, and the two will not have the same flow. Much less fluid will reach the passenger side.
I only know this because there was a similar system set up on my old CJ 7, and I was broke and couldn't afford two check valves, so I didn't use either. I got the above-described behavior for my troubles.

[jkevinc]

If you have the high intensity washer system as part of your build, I believe the check valves are both necessary to keep the fluid from flowing into that additional reservoir and over flowing it when you activate the sprayer from the main bottle.

[cabmandone]

UGH! Got my replacement pump in a few days ago but also had surgery on my knee.. So feeling better today I hobble out to my shop and excitedly install my new pump. I turn the key to the on position, pull the washer arm and NOTHING!! Now I've got no power to the pump... Son of a....

[Superman]

Originally Posted by cabmando

Nope! I refuse to learn from the mistakes made by others! I must make the same mistake.

This has long been my approach, and I also consult repair manuals only when I ran into problems. Then, a few years ago, I started doing the research BEFORE doing the work. This new method works exactly like the old method did, except that the work has become faster, easier and less expensive.

Another policy of mine is to try to out-think the Porsche design engineers almost never. On the topic of windshield washer check valves, I assumed the engineers had reasons for using the parts they did. And I just got a whole new system except for the tank and pump. New hoses, fittings, squirters, etc. It is likely I avoided some aggravation this way. And finally, I notice the check valves are not designed and built to NASA specifications. They're pretty simple and depend on plastic parts mating together perfectly, which may not always happen. Also, vehicles vibrate and shake, and change temperatures. In theory, one check valve should be sufficient. In the real world (where I live), maybe not.

[Superman]

Take the rest of the day off, Nick. I think this is also the doctor's advice. I too am a perpetual motion machine, so I understand. The advice doctors give us is important, however. Do some research or something. Go argue with the guys on PARF. That will improve your peace of mind.

[cabmandone]

I'm going pretty easy on my knee. Just thought I'd try to get this washer system working as my last little project but noooooooooooo... the damn thing refuses to cooperate.