22-11-2021, 10:29 PM
(22-11-2021, 09:57 PM)Ian Williams Wrote: Why so small, I guess they were limited for space, but it is this area between two exhaust posts that the blocks need cooling, and part of the reason, I believe, some crack especially when combined with over tightened head studs. The water way's around the exhaust ports is very small and very often seriously clogged with corrosion, a problem which is made worse by owners fitting studs where the threaded portion is too long. I have sectioned a couple of scrap blocks to see how the water passages work, once you can see it becomes easier to clear the accumulated detritus with various picks, rods, drills and modified hacksaw blades, yes removing the adjacent head stud helps this quest. Unfortunately I don't have any picture of the blocks I sectioned that I can post on here to help you Jon, the blocks have been in storage in Auckland since have moved to Wellington.
Hence the suggestion to drill out the core plug about 2 o'clock to the front welch plug and clean out the waterways, putting in a threaded plug to facilitate future cleanouts.