09-07-2018, 07:46 AM
(This post was last modified: 09-07-2018, 07:49 AM by Murphyv310.)
The engine was very quiet when new but after a couple of thousand they got noisy.
The issue was poor materials (bad case hardening on the shaft or lack of a bronze bush on the rockers) or even lack of oil to the rocker shaft as it wore. No amount of adjustment would ever cure it.
One or two were returned under warranty with new shafts and rockers fitted, again fine for a couple of thousand then it gradually returned. The snag is they also went from being really nippy to sluggish as the valves didn't fully open once all the wear set in.
The issue was poor materials (bad case hardening on the shaft or lack of a bronze bush on the rockers) or even lack of oil to the rocker shaft as it wore. No amount of adjustment would ever cure it.
One or two were returned under warranty with new shafts and rockers fitted, again fine for a couple of thousand then it gradually returned. The snag is they also went from being really nippy to sluggish as the valves didn't fully open once all the wear set in.
