INSPECTING THE CRANK, BLOCK CAPS & PISTONS
Our local 1 machine shop, W Drake, took one look at our main bearing caps and could see they had been work-hardened. Due to the bearings having spun around, the heat build-up hardened the metal and distorted the shape of each cap.
Refitting the 2 old main caps to the block revealed further problems. Having distorted, they were not a tight fit. W Drake recommended sourcing and fitting an earlier set of secondhand caps, which we found were a tighter fit. These will need to be line-bored.
We were 3 worried the cylinder bores might be damaged, but W Drake measured them and visually inspected for score marks – they were all in good condition. Note the markings around the top of each bore; this is a hardened material to prevent wear and seems to have worked.
We were similarly 4 lucky with our pistons. There was no sign of damage to the tops, sides or connecting rods, and the big end bearing caps and adjacent conrod were not distorted. All we needed was a new set of piston rings.
Sadly, our luck ran 5 out on the crankshaft. A crack test revealed a hairline fracture across one of the journals. W Drake managed to source a secondhand crankshaft for £300, which will be tested and then ground and polished next month.