18-12-2019, 02:42 PM
The engine on my RP was rebuilt professionally only 1000 miles (but about ten years) ago. When I got it the car had covered only 300 miles or so since the rebuild. It developed a major oil leak which I tracked down to the Austin square headed 5/16 BSF special bolt that locates the camshaft bush. I lifted the block slightly so I could remove the bolt with a view to reinstalling it with some sealant. Having inspected it and observed the absence of much thread in the crankcase I shall remove the camshaft and redrill the bush and tap it to take a 5/16 cap head bolt which I'll seal with a Dowty washer..
I can see how the original installation when the engine was built at Austin's would work, with good threads in the crankcase and a tight hole in the bush to take the pin, there would be no movement at all. The little bit of wear that must have been present when the engine was rebuilt has allowed the camshaft's tendency to work forward to bear on the pin, which you can see is bent, and so erode the threads in the crankcase leading to my "gusher".
Interested to know how others address this problem.
I can see how the original installation when the engine was built at Austin's would work, with good threads in the crankcase and a tight hole in the bush to take the pin, there would be no movement at all. The little bit of wear that must have been present when the engine was rebuilt has allowed the camshaft's tendency to work forward to bear on the pin, which you can see is bent, and so erode the threads in the crankcase leading to my "gusher".
Interested to know how others address this problem.