windshield washer not spraying

[kru0042]

Hello All,

I am back with my 4th 450 SEL. It is a low mileage (152000km) for a 1977 with clean body and runs great. My other cars were all newer and had the more modern combination switch which operated the windshield washer fluid pump. This one has a foot switch, but I can't get any fluid to pump. where is my starting point in diagnosing this problem. Its amazing how everything else in the car works. It was owned by a MD and was garaged its whole life. Even the rubber exterior trim is pristine!! Thanks and cheers from the Great White North.

[ziper1221]

For me, I just pulled the pump out, disassembled it, and spun it by hand. Try that, on my 300SD it was located on the passenger side longitudinal support beam under the engine.

[oversize]

Can you hear the motor working when you depress the switch?  If not check the fuses and then (with the help of a friend) see if you have power to the motor by operating the switch with the igniton on...

If the motor does run it could be a blocked hose or a stuck check-valve.

[Kjhall65]

I have the same system in my W115 and have had the same problem.  The issue in mine was a split in one of the hoses.  It was leaking air and without the vacuum pressure the pump was unable to get the fluid to the washer jets.
Ken