I am not a clean freak,but,In a certain chemical plant that we frequent we must use vegatable oil for hopper spray oil.Man,I guaruntee that vegetable oil is THE WORLDS WORST spray oil.Do you remember pine tar on wooden baseball bats,that is the only way I can describe how veg. oil works on the hopper.There has to be a better biodegradable type of oil that does not turn into a major mess.It was so stinkin sticky and nasty I had to laugh....

prime a pac make a hopper spray called willieshield that is biodegradable safe for concrete,asfault,non greasy on the pump builds up like a wax film when sprayed on and given time to dry. i usually spray on at night when im finished with the day .concrete pumping is a career not just a job SMACK

Diesel never seemed to work for me by its self, it always to evaporate it does work good if you use it to cut motor oil 50/50. But the best thing I have ever used is automatic transmission fluid cut with mineral sprits 75/25 It really does the trick.Jeffwhen in doubt wash out.