i tried cillit bang for engine cleaning, didnt do owt, got some floor cleaner from work (yellow alkaline stuff, proper strong) sprayed it all over, let it soak 5 mins and sprayed it off with a hose, good sh!t

so strong it foams up on ali, ace stuff
gotta be careful tho as more than 5 mins id imagine it'd start eating away at the paintwork lol
