I found a relevant thread for my question using the search feature, but it was in a weird part of the forum, so I wanted to post it to this forum because I think it's more likely to get seen.
I am about to winterize my Sparks, and I want to replace the plugs as well as this is the end of year 2.
The parts guy told me not to put the new plugs in after I fog the engine, because next year when I start it up, it will foul the new plugs.
I am going to follow his advice, which means removing the top when I service them, and then removing the tops again next spring when I get them out of storage to replace the plugs (after I run them for a few minutes to remove the fogging oil).
I guess my question is what is the difference between new and old plugs with regards to fogging the engine? If you didn't plan on replacing the plugs, wouldn't you foul your plugs when you start it up in the spring, regardless of whether they're new or old plugs? Therefore, any time you fog the engine for winter, you better have new plugs on hand for the spring?
I hope I'm making sense, it just seems like fogging the engine leads to bad plugs, which leads to replacing plugs every year.