I have Kohler 20 hp command that I use for carpet cleaning. The motor is inside of a chevy express van. The doors are all open when the engine running. The engine has 1540 hrs on it. The main shaft seal came out and a oil leak. I had the new seal installed, but still have small leak.If I purchase a new motor same as this one I hope not to have the same problem. I don,t think my old motor has a oil cooler ? and would like one on the new motor. I,m located in FT Myers Fl very hot & humid. I don,t have employees and have been doing this for 35 years and I,m 74 yrs young ans still learning. Any advise will help. Thank you . jz.