Diaphragm Box

Checking







If the basic boost pressure cannot be adjusted, check as follows:

1 Check that the push rod moves freely and does not bind.
2 Check the diaphragm and spring by pumping up the pressure via the diaphragm box's nipple. Check that the pushrod is pressed out and that it displays no tendency to bind. Release the pressure and check that the pushrod is pulled back into the box.







Change the diaphragm box if it is defective.