B44 Victo Special inlet pushrod.

[nickdun]

My 69 B44VS keeps destroying push rods.  They are getting shorter quickly.  I pulled the rockerbox in October last year and replaced both pushrods.  The exhaust one was fine but the inlet one was 1/16'' shorter.  Now a few hundred miles later the inlet valve clearance is opening quickly.

Any ideas?  Dodgy rods, cam followers?

[Briton-2191]

I'd start at the top-end and work downwards to minimise dismantling...
Could there be excessive friction between the inlet rocker and the spindle shaft that it rotates on?
Wrong inlet valve spring - too high load?
Did the problem manifest recently, or is it long-term?