What causes hydraulic pump noise (ticking)?
I find myself pondering what actually causes the 'ticking' noise from the hydraulic pumps. My first thought is 'lash', as with valves. That would imply wear, possibly, of the camshaft lobe or the pump's pushrod. It seems that the only repair for this is a new pump push rod (or cam). Ouch!
I then began thinking what else might cause this problem. Many of you have reported that your pumps 'tick' until warmed up. Mine get quieter when warm but the sound is still there and audible from the interior with no accessories switched on.
My car has air in the rear hydraulics and therefore needs to be bled. That got me thinking that since air is very compressible, it is the hydraulic equivalent of 'lash'. Could this be the cause of my pump's noise?
What else might cause the problem? Incorrect hydraulic/brake fluid? Gremlins?
I would certainly like to make this engine sound quieter.
-rick / '69 R-R Silver Shadow