well, gunk engine flush does work a little...

[eldawg4100]

my dad had to try some of this crap. the 5 minute engine flush. first, he put some B-12 in the engine with his old oil, ran for 5 minutes, drained. then we re-filled with plain bulk dino oil, ran for 5 minutes, drained. then filled again with dino and gunk. 5 minutes

the oil came out VERY dark...must have disolved a lot of junk!

then once again, we filled with plain dino, ran it, and drained it.. it was CLEAN, looked brand new.... so the gunk must clean pretty good since before that clean oil came out dark in 5 minutes...

 

[digitaldrifter91]

gunk no doubt cleans it but it does it with strong solvents. when u put oil in and drained it again nothing came out black cause oil alone cant get crap out. there have been many posts on the affects of gunk and really its strong. some people say that the seals will be eaten up or not fully sealed. if u have been in this forum everyone is trying auto rx that will clean the whole engine and in small spaces that gunk cannot remove in 10 minutes. but hey, if it works for u then cool. i used gunk one time in the past, lol it blew my head gasket somehow hahah.