Why do L-Head studs break so easily?
Here are some reasons I believe that the L-head bolts break: 1. Corrosion- Far less was known about metallurgy in 1947. The quality of the steel in a modern bolt is far superior. Modern machine bolts are less susceptible to corrosion. 2. Stress- With V-8 the only time a head bolt is retorqued is when the valve cover is removed and usually not even then. With the L-head, the bolts are on top of the head and fully exposed. I know my dad used to make a ritual of retightening the bolts on the top of the engine every spring (Just in case one came loose). And if you blew a head gasket the first thing to try was retightening the bolts. Do to stretch/stress, it is a good idea to change the bolts at least every other time you replace the head gasket. Since this usually isn’t practical it usually isn’t done. If the head bolts are grade 5 and you replace them with grade 8 I believe there are some things to consider. Unfortunately my knowledge of shear strength and such is very limited so I’m hopi
