Yeah, that whole paint thinner/mineral spirits/naptha thing kinda confuses me too... I think they are related, but are chemically different.

Paint thinner is mostly mineral spirits mixed with some other chemicals in small amounts. Its like 1.50 a gallon at walmart. Virgin mineral spirits is much more pure, but its like 1.19 a quart. Naptha is the main ingredient in Zippo fluid, and its also used in some camping stoves and lanterns. Its more flammable than paint thinner or virgin mineral spirits, and may evaporate faster.

Can't really say about what to use on valve stem seals. Maybe somebody else can?

Chiphead


Preaching the Hot Rod Gospel according to the 4-stroke apostles:

Suck, Squish, Fire and Fumes