....and if the lubrication problem, if there is one, is not sorted, the new lot will wear out in no time too. Before you take off the old stuff, I would make sure you have oil coming out between the rockers and shaft with the engine idling and rocker cover off.. Give the engine a couple of flushes and get the oil fairly clean before throwing new bits at it. God I hate these engines...! Most of them were knackered by short journeys and lack of oil changes. They tend to blow quite a lot of carbon past the rings which shits the oil up and needs getting rid of regularly... which it normally isn't!