SL/R230: headlight washer problem
moretech
Last edited by moretech; Oct 31, 2016 at 11:47 PM.
thanks much
moretech
moretech
moretech
Last edited by moretech; Nov 3, 2016 at 11:43 AM.
Well with some real research this problem is solved cheaply. What was needed was some calculations and checking with several industrial supply companies for a check valve with a suitable cracking pressure. This style valve inhibits forward flow and backward flow of fluid. The trick is how much cracking pressure do you need to stop downflow from the reservoir and yet not inhibit nozzle operation and is such a valve available of suitable psi cracking pressure. The answer I had calculated was about a 0.7 to 0.8 psi check valve cracking pressure which I could not find built on a one off basis. But did find a 1 psi cracking pressure valve. This one #22173 from US Plastics did the job. I inserted it by cutting into line 270 shown in the diagram above and I put on two small worm gear hose clamps due to the high pressure of the system. The high pressure of the pump overcomes the 1 psi cracking pressure of the valve easily. System works fine with one small caveat. Nozzles will slowly, but completely retract as water leaks from the broken seals of the nozzles but NOT from the reservoir. Retraction may take a few minutes but finally they completely retract. Apparently there is a two way valve in the nozzle assembly allowing flow both ways to quickly open and close it. The check valve completely stops any back flow which causes the slow retraction of the nozzles. But this approach still does the job and for me solves the problem well enough rather than buy 2 new nozzle assemblies near $112 apiece. I hope this may help someone else with leaky nozzles. If you only have one leaky nozzle this may not work. The non leaker may stay up! You can access the line quickly by removing just the small far right side lower trim panel.
moretech
Last edited by moretech; Nov 21, 2016 at 02:04 PM. Reason: clarify some things
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Thanks,
BrianA.

No direct knowledge to share. Hopefully someone can chime in with actual experience. I'm attaching the WIS instructions. Looks to be fairly easy, detach fender liner and front bumper then pull out for access.
If you decide to DIY, be sure to add any shortcuts or tips in a followup post.
Good luck,
Bob
moretech



BrianA.
all the best to you on the repair.
moretech


