Washer jets, wipers, above or below?

[guyd]

Traditionally, car wiper squirters are below. For good reason, that at high speed, eg 70mph, the clean water will progress across the screen and then be wiped.

My boat does what, 22 knots tops. That’s a moped speed (slightly depressing). Wind isn’t going to push the water up the screen. Gravity wins....


So, my cheapo universal wiper squirter kit, eBay special, jets on the roof or roof brow, or traditional? ‘Glass’ is about 45 degrees, heavily wrapped around.

 

[William_H]

I think most washer jets squirt from the bottom up to near the top simply from pressure. I don't think 70mph is relevant. So you should fit yours at the bottom. olewill

 

[PaulRainbow]

I think most washer jets squirt from the bottom up to near the top simply from pressure. I don't think 70mph is relevant. So you should fit yours at the bottom. olewill

I'd agree with that Will. Previous mobo's i've had have been at the bottom too.

The 70MPH comment is wrong, windscreen washers work when the car is stationery.

 

[rogerthebodger]

The washer jets on my boat are along the wiper arm that spray along the blade

I got my wiper arm and blades from a bus so are quite long.

 

[TLouth7]

Washer jets on cars are quite clever really. Clearly at high speed they need to be below because you are not going to be able to spray water forwards against the 70mph airflow.

They should be aimed so that at low speed the jet hits somewhere in the top half of the screen, and runs down. At higher speed the airflow forces the jet down, and so it hits in the lower half and runs upwards.

My boat has no windscreen, so no wipers, and certainly doesn't go at 22 knots. I guess you could just have a reservoir above the windscreen and rely on gravity to dispense water? Perhaps with a leaky hose type arrangement to distribute it.

 

[[163233]]

Perhaps a bucket?

 

[Spirit (of Glenans)]

If you go at 22kt there will be plenty of water on the windscreen