Some religiously use oil additives and even gasoline additives. I know it because the auto parts stores continue selling them. So do they do you good? Are they worth your money? How do you know? Check some out.
Every once in a while I run the stuff that's supposed to stop deposits in the engine. I don't know if it's worth it or not, but it's not a big expense.
The link is gone, but here goes. Sometimes we'd get caught in a fierce downpour with mowers on the trailer and get water in the gas and nothing but sputter on the next start. HEET in the bright yellow bottle worked wonders. For stuff in the fuel system tougher to deal with than water Sea Foam worked often, but not always. I'd rather try just about anything than drop a float bowl in the field and start punching safety pins into little holes. Yeah, I know, by theory water cannot possibly get in the fuel system. I've only seen dramatic, almost immediate good results with HEET and Seafoam. I think there are Lucas products just as good, but you might have to hunt for them. Stuff that you throw in the gas for fuel injectors -- I doubt it could hurt anything, and it may help. Long ago I remember guys throwing a pint of kerosene in a full gas tank and swearing it kept the mechanic away.
I have yet to use either product. Seafoam was tested to handle bolts and nuts rusted in and Seafoam came out first place. Kerosene contains a lubricant quality if I recall correctly.
