The PO had changed the original engine out...without modifying the waterpump so that was the first major undertaking. The engine showed good compression, and with a little tweaking she fired up...good oil pressure....that was great news. The bad news was that the timing gear had a really pronounced growl....I have a hunch that the original fiber timing gear was replaced with an aluminum gear and the original bottom crank gear wasn't changed. Timing gears come in sets and the "growl" was due to a minor misalignment. I've been assured that the growl is not fatal...just annoying. I will eventually replace the engine!!! NOTE: The growl that concerned me had no effect as I drove the truck for almost a year with no problems...other than the growl. It's been changed out to a fully reworked 1960 235 that is as smooth as goose grease!!!!