What is best used for cleaning off an old Mercury after years of old oil and grease deposits, used Sea Foam got a lot off but not everything, I saw a post on this topic but can't find it, thank you
How old is old?
For antiques, I like using a mix of dawn dish soap and ammonia. Maybe 2 parts water to 1 part ammonia, add enough dish soap to get your level of suds you want, then use a light brush to get most of it off. The ammonia breaks down grease and oil fairly well.
Yeah, then you want to be fairly gentle with it. Anything harsher than that and you might start damaging any decals that might remain on it.
I've found that if you run the engine for a bit, get it nice and warm (if it's in condition to run), then spray a cleaner in it, it will penetrate deeper and clean more
