RSav

Hi Matt88 Just being lazy: yep, just a simple tee similar to this: I will add a non-return valve in the feed tube. Regards Richard

I think that the nozzles are clear - purely on the evidence of swapping feeds between the nozzles, i.e. the poor performance is caused by the reduced flow from the backwards pointing outlet from the tee piece. I may replace them just for completeness but I am going to fit a simple tee in place of the Lexus item.

Thanks, yep the pipes and jets are clear. Small fire-hose effect when the tee piece is removed from the hose from the pump. The uneven flow appears to be solely a function of the tee piece. I visited my mechanic this morning and his comment was that he's seen it on all the Lexus' that he services, cannot understand why Lexus complicate things and his solution is to fit a normal tee piece which restores maximum flow to both jets. As an aside: I was surprised that such an expensive motor does not have a dirt filter in the neck of the washer bottle. It's the only vehicle I have owned (list: Classic Range Rovers, Discovery, Skodas and Shogun) that has not had a filter. I queried it with Lexus and they said that they didn't consider it necessary! Cheers Richard

Swapping the hoses between the outlets from the valves moves the reduced spray i.e. it results in the passenger's side becoming weak and the driver's side becoming strong. There's only one part number for these tee pieces across the whole Lexus range - as far as I can see. Ditto the jets.

Thanks Ace8800 - there are no daft questions! Plumbing is per the attached drawing. Triangular flow arrow is shown. It seems that the valve intentioally restricts the flow to the outlet which points backwards. In my case, it's the feed to the driver's jet. It appears to be an attempt to balance the flow in washer hoses of unequal lengths. I'm very tempted to source a conventional NR valve and an open tee piece. Cheers Richard

Is there any possibly that Lexus uses two versions of this valve, one for the feed from the passenger's side (the one you bought) and one for the feed on the driver's side (unknown part number)? My reason for asking is that my wife's RX450h is suffering from weak spray on the driver's side and I duly bought and fitted 85321-28020 with no improvement. The feed to the tee piece on RX450h runs up the driver's side of the bonnet.

Good evening. My wife drives a 60 plate RX450h. She has complained the screen washer spray on the driver's side is much weaker than on the passenger's side. My investigations lead me to conclude that the tee piece was faulty and I duly replaced it with another 85321‑28020. Unfortunately the pattern etc is unchanged. It appears that the tee piece intentionally reduces the flow to the driver's side because I have found that swapping the outlet pipes to the jets around swaps the weak spray to the passenger's side and the strong spray to the driver's side. On the attached picture of the tee peice: red = flow from pump, green = driver's jet and blue = passenger's jet. I have, gently, cleaned both washer jets with compressed air but this has not changed the, apparently, correct operation of the tee piece. My thoughts are that I should replace it with a conventional non-return valve and open tee piece. Has anyone else found a solution to this conundrum? Thank you Richard