chris7ian wrote:Thanks for the quick reply - I might be being stupid but I can't find any reference to vacuum pumps other than for diesels... am I missing something?
Chris....he was replying to the OP....your issue is rear drum brake adjustment on the shoes. The clearance between the shoes and drum is too large which typically leads to longer 'initial' foot pedal movement, higher with a second 'quick' application. Although, a very small amount of air in the system can have a similar effect, however the brakes would generally feel on the 'spongy side'.
When driving, pull your handbrake up just before it starts to work, now try the foot brake....if it gives a good high foot pedal on the first application this would back up the theory of excessive shoe to drum clearance.
As for the OP: I agree, mechanical vacuum pump issue, or perhaps a leak somewhere in the vacuum pipe, however, with the engine turned off, have you got two pumps before the pedal goes hard? This is the normal test for the servo/one way valve.
In my experience, T25's don't have bags of vacuum reserve and it seems pretty normal to exhaust the vacuum on the third pump, although I guess this may vary...The pedal going hard on the second pump does sound like an issue.
Martin
