I believe I have a LP Fuel problem. engine will not fire Lp Gas. Replaced Regulator New. Replaced main Fuel injector New. Cranks won't start or Fire. Spray starting fluid in breather Fires. I believe fuel is tainted. Maybe Fuel is blocked from making to throttle Body. Before replacing regulator I had old one rebuilt and tried a good used injector and got it started but shut off in 1 minute. I have followed advice of Forklift Mechanic after replacing recommended New parts has no answers. Can anyone help suggest next moves ? My father was 35 yr forklift mechanic he is elderly and only suggests Ideas