I'll look up the year & post- as far as the regulator not passing fuel- the regulator needs to feel a vacuum from the mixer (curburator) before it will pass fuel. The engine is a Continental- used on millions of lifts- good reliable industrial engine. The sticking valve surprises me- I've never seen that- even on engines that have sat.

It should have a Delco distributor installed- parts for it are available at NAPA- I'll look up the part #'s if you need. The engine oil looking like a milkshake is probably from condensation buildup from the engine constantly being started, run for a few minutes, then shut off. The key to look for is- is the oil overfull? If not, replace the engine oil & filter, run the engine till hot, shut off & replace the engine oil & filter again. Depending on how loaded up the engine is, you may have to do this numerous times to get the sludge out.