Winch Engine Broken

Those who operate vintage engines like the olds 455 and the Chevrolet 454 should be aware that these types of engines from the 1960's to the 1980's employed a hydraulic flat nose camshaft and tappet followers which requires a high heavy metal component in their lubricating oils (Zinc phosphate etc) these oil formulas have been mostly replaced by ecologically safer oils which do not provide the lubricity and extreme pressure additives to allow these valve train designs to survive any length of time at all. Failures can occur in hours not years. an expensive stopgap measure is to use one of several race engine blends of oil, or replace the valvtrain with a full roller bearing configuration. the replacement option is really only viable if you need to keep a valuable classic car running, as retrofit roller valvetrains can run into the thousands of dollars.
A much more economical option is to rework your winch to use a commercial diesel or modern truck engine, while more work now, using 50 year newer technology will pay dividends for years to come.
Best wishes,
Scott