Re: A question about headlights & Bijur system on a '32 901

Posted by Owen_Dyneto On 2014/11/1 13:05:41

If you're referring to the vacuum powered automatic Bijur, the pump pressure is determined by the spring that drives the piston downward after manifold vacuum has withdrawn it. Never measured the pressure but expect it is quite low, probably not more than 10 or 15 psi. To function all it really has to overcome is the felt filter in the drip plugs plus whatever small frictional looses occur in the tubing enroute to the drip plugs.