Headlight vacuum problem

Hi all, when the headlights are up on the car, I can hear a ver slight sucking noise ciming from the front of the car. Sounds like air being sucked in, nothing too bad though as the car still idles fine, I don’t want to run it with them on and then nip or hole a piston with the weak mixture? How are the actuationg cylinder fo leaking. The chassis is fine as the tank was plated with 1/4 plate when the car was rebuilt!
Al Cowan

The little hand vacuum pumps are great great for checking the pots,etc, one component at a time, just watch the gauge for leak down. My pots had to be brazed, they collected moisture in side and rusted thru.

Hi

Serious leaks will make a sort of ticking sound as the No1 cylinder sucks. If you get a bit of hose and put it to your ear you can track down even small leaks fairly easily by running the other end along the pipes.

Berni

My head lights stay down for months!

I had similar problem and also noticed that under high revs the headlights started popping up. I replaced non return valve in airline with one from Norgren Martonair (same as Lotus one but 1/3rd of price), replaced all hoses with heavy duty nylon with push fittings normally used for compressed air lines and got local fab shop to make up stainless reservoir situated in nose cone that can be taken out and periodically emptied of any vapour / condensation.