Headlight vacuum failure

[Uboat]

Hi,

My headlight vacuum system has stopped working, and the pods stay up all the time due to the failsafe function. I have examined the hoses, the vacuum tank in the frame and the couplings. I haven't found a leak and there is vacuum building up, so I'm thinking it must be the solenoid.

On my late +2 (1974) the solenoid is located on the left flank close to the overflow bottle, as seen in the photo attached. My car is lhd and maybe it is on the right flank on rhd cars...

When I turn the headlight on and off with the switch on the dash (when the motor is running) nothing happens with the solenoid. Is this in order, or should you be able to notice any movement or action when activating the system? Could it be anything else that doesn't work? Where can I find a new solenoid?

Any thoughts on this?
/Ulf

[terryp]

Hello
It looks as if the button is out too much. When you switch on the headlights the button locks down. Why don't you try and press the switch with the lights on to see if it locks. Then I'd take the switch off , take apart and reassemble again with silicone grease. You need to adjust so that the air flow is at the miminum to let air through when the button is pressed
I had a switch exactly the same but with a dodgy seal. I tried to fabriacte a new seal but ended up with a new switch from Steve at SJS Sportcars.

Regards
Terry

[Uboat]

Thanks Terry,

I will examine the valve on the switch. What is the standard position of the "button". Should it stay in close to the center (right on the photo) when lights are off and move to the left when headlights are turned on?

[terryp]

Hello
When the lights are held down and off the switch is as the picture. When the light switch in the car is turned on, the solenoid acts and the button goes in and releases the air , pushing the headlamps up. (presumable being a 1974 has the failsafe headlights)
Hope this helps
Terry