Windscreen Washer Advice

[crashbarrier]

To start with I had very little flow from the washers, more a dribble, and I've been doing some investigating. I've replaced the wipers and washer heads as an alternative to the original loop type but instead of a fountain, I'm getting a pathetic attempt to spray. I've finally managed to extricate the reservoir after it resisted all attempts to '"just push up". It's nice and clean inside so no expected sludge build-up and the motor seems to whirr away quite energetically when energised. The washer hose seems to be nice and clear inside when I wipe away the outside crud so I then wondered about the non-return valve.

Non-return valve - It's located just along from the reservoir and when I disconnected it from the upstream hose lots of lovely blue wash fluid flowed out from the hose above which leads me to believe that it's not sealed or partially blocked further up towards the wipers.
I've tried to blow through the valve in the correct direction and it seems to be blocked as there is hardly any flow of air but there is a little.
I've rigged the system up without putting it back in and with the valve removed the flow at the wipers is a bit better but still not great.

Q. Is the valve supposed to be so resistant to being blown through as I can't imagine the pressure from the pump is much? I did a test with a blow pump as well as my lungs but to no avail.

Q. Could I just leave the NRV out of the system? I presume that it prevents the fluid in the hose upstream from slowly feeding back into the reservoir under gravity so it'll mean a wait for the water to flow and some dry wiping.

Q. With valve removed could the pump simply be on its last legs even though it sounds OK and just not producing the pressure needed to re-create the Bellagio fountains?

I'm trying to resist just blindly buying new parts in the hope that I resolve the problem but if the advice is to do so then.

Any advice gratefully accepted.

[Belle427]

In my limited experience you should be able to blow through it comfortably in the direction of flow.
I’d usually blow through the line with some compressed air just taking care with pressure but not everyone has a compressor.
Halfords stock all the washer tubing etc, may be worth rigging up a new length of hose temporarily from the pump to observe the flow and go from there.

[crashbarrier]

Thanks, Belle427,
Unfortunately, no compressor to hand and anyway I can just imagine the damage I'll cause as the valve shoots across the garage as I test it. I'll dive out and get another later this morning.
I'm going to test the flow properly later with the NRV removed as well as in place. I might also connect up the old loops to see if they are any better as by swapping the washer heads I've gone from 4 spray holes to 8 which will reduce the pressure. I've ordered a cheapo pump from eBay which even if it makes no difference will be handy as a spare.

[Bowks]

I've just gone from the loops to the 8 x nozzles. the flow is still great. Or it is now I've reconnected all the joints behind the dash. Stick with the nozzles.

[crashbarrier]

Good to hear, Bowks, so I'll plan to stick with the nozzles and look elsewhere for the issue. I'm keeping my fingers crossed that it doesn't turn out to be a pipe blockage in that bulkhead void.

[sixor8]

My loopy tubing had been replaced and wasn't prepared properly, the holes sprayed all over the place. I just went for these:

https://www.ebay.co.uk/itm/373561431548

With some 4mm tubing, works well and total cost under £6.

[crashbarrier]

sixor8,
They are the same spray heads that I've now got and there was very little improvement. It's the supply of water to them that is the problem so, tomorrow, I'll test the system with the NRV removed, then a new NRV in place and finally next week a new pump fitted when it arrives. If the pressure is still pants then it's the tubing from the NRV to the bulkhead exit so I may just run a whole new line.

[sixor8]

The heads of the jets needed moving with a pin for them to work properly for me, otherwise they just hit the arm they were clipped onto or shot fluid over the edge of the screen. Sounds like it may be your pump if you can't find a leak or a faulty valve.