Hi all
Spent an hour or so looking into the rocker shafts lubrication. Going by the diagram in the workshop manual I have there should be an oilway running the full length of each head with a spur off to each rocker shaft. In reality on the three heads I have the oilway comes into the 'reservoir' for oil under the front rocker shaft pillar. From the first pillar there is a hole leaving here and entering the second rocker shaft pillar with another hole leaving here to go into the third rocker shaft pillar. There is no second hole in the last 'reservoir'. I assume then that the oil enters the first reservoir then is forced into the second and then the third. I had a look at the rocker shafts on my spare engine and they too have marks on their surfaces that look like they have been running dry, interestingly the 'reservoirs' still had engine oil in them as with the engine flat a proportion of the oil trapped can not drain away thus aiding start up lubrication. As an experiment I filled up the three 'reservoirs' with oil and set the head down with the rear end slightly lifted. The result was what I had expected, the rear and middle 'reservoirs' drained down to the level of the holes (these are right next to the studs and hard to see) that feed the oil through and the first 'reservoir' drained completely with the oil dripping out from the hole in the face of the cylinder head. Weakness with this system would be that if the hole leaving the first 'reservoir' is blocked then the next two will be starved of oil. I think the diagram in the workshop manual may only refer to earlier cars or is an idealised view of what is going on. I would welcome any comments on this.
Clarkey
