Rear washer "piddles".

Thanks to a fellow member my rear wiper system is restored and working with 1 problem. With most accelerations the squirter leaks- alot! In order to save fluid I have reversed the check valve in the line and just for fun tried to squirt it, which it would not, not even a drop. What am I missing here.

Thanks.

Kerry.

Kerry

Do you mean the pump that's on the tank or the nozzle that's on the wiper arm? I think you are talking about the nozzle on the wiper arm. I think you're talking about the nozzle, if so, I would it is plugged. You need to clear the hole either by air or maybe a pin.

Tom

Hi Tom,
My problem is the nozzle expels fluid with the inertia from acceleration. I flipped the check valve to stop the flow out the nozzle. I only tried it with the check vave backwards to see if the check valve was working correctly which it is.

I wonder if the pump is weak or needs replacing, it is on the tank where you put the washer fluid. There should be two pumps, one for the front windows and one for the back.

Tom

Hi Tom,

Both pumps are about 5 months old, aftermarket from NAPA if memory serves.

Check the grounds and connectors on the pumps. Our 96 RMW had a issue with that that made them run poorly most, but not all, of the time.

The pumps are working fine except that the fluid dribbles out of the rear nozzle when I'm not using it.

Thanks.

Kerry.

The rubber washer line that runs past the spare tire loops up to the highest point in the fender well before going into the roof. Check to make sure the line is fastened up as high as possible and has not fallen down.

If it is dribbling when not running but from acceleration, high odds the checkvalve is still holding in the backflow direction, but not "springy" enough to hold against the minimal force from acceleration. I would try a new check valve.

Hi Tom,

I didn't know it had a function in the opposite direction, thanks.

I don't suppose I could still by one. Is there a comparable unit available.

Kerry.

I think the vacuum checkvalves work with the washer hose size.

Rock Auto $6 shown as for the 96 wagon.


Check valve

The check valve keeps the system from draining back to the washer reservoir, which is lower than the wiper nozzle. If you can blow through the check valve one way, but not the other, it is doing all it was designed to do.

That's the way I saw it too. I will check the hose routing in the spare tire cavity as you suggested.

Thanks.

Kerry.

Check valve usually have a rating spec called "cracking pressure" which is how much pressure it takes to open the valve and allow flow. It would be the same amount as what could be referred to as the closing force built into the valve. You normally don't see specs like that for automotive stuff at the public level. The force that holds it shut can be a spring or even just the force that a rubber flap can exert. A brake line residual pressure valve does the same thing but is a low pressure checkvalve toward the rear brakes and a higher pressure check valve away from the rear brakes.

The force of the acceleration sounds like it is just enough to be higher than the cracking pressure in the checkvalve in question.

You can cheat a bit and give a valve that is opening to easily some help by putting it at the bottom of vertical run of the tubing. This gives a bit of head pressure on the closing direction of the valve as long as that vertical section is not closed off at the end of the hose and the nozzle should be open to take care of that.