Ok I will only be using my welder now and again and for probably up to around an hour, do I really need 17lts of oil in it or could I get away with say about 12 lts, after I cleaned all the internals of it and let it dry out I switched it on and welded on 80amp for 25 mins it was hardly warm so my question is would 12lts keep it cool enough. Thankyou.