Hi, CaptJ- You are way out of your depth here so just admit it. I know well the described procedure for Calibrating the Dip Stick. Just how many boats can you actually drain the sump by using the Drain Plug on? The small boat builders you refer in your posts would in my opinion and experience be more likely to have to call in outsiders to do the engineering for install and alignment etc than the bigger ones. A lot of the bigger ones have come to build yachts from building ships where the whole structure and procedures differ from what you are used to with you little fishing boats yet you are pouring out info like it applies to ALL CAT product in all yachts. Where do you get this odd notion that CAT has different DEO for different hemispheres? There are different grades of multi Grade oil the one you used depends upon the ambient temperature where the engine is operating. CAT only specify a monograde oil for the 3116 and 3126 Marine Engines with mechanical unit injectors. It is available as a 30 or 40 Wt Oil and is not to be used in any other engines. It is to be used where the engines use a closed loop crankcase ventilation system. Here is the CAT Literature about your "special" Oil.