Hi Grumpy
Thanks for the details. I've got a new rocker arm and I will run through the checks that you've outlined. This is a lawnmower not a pressure washer. When I've put a new rocker arm on it runs great for a couple of cutting grass and there is no indication of any thing wrong until go to start it for the next round of cutting the lawn.

It will be a couple days before I can get back to you on what I find.
Thanks
Mike smile