Oil Fill and Drain
At one of the top corners of the oil loop a small pipe will continue upwards. This will be the highest point of the oil loop system.
The pipe will hold a small amount of extra oil to ensure there are no air bubbles in the system.
This pipe will have a fill cap that can be removed in order to add more oil. The oil level will be check regularly to ensure its is at the correct level.
The pipe will also have a very small breather hole or low pressure two way valve to allow the oil loop to breath in and out as the oil expanse from heating and cooling. A filter will be used to ensure very little moister or contaminants enter the oil. The breather does not allow any significant pressure in the oil loop as this will only cause leaks and stress on components. If a pressurized system is required because the system must operate at high temperatures a safety release valve will be used (see design choices 4)
On the opposite lower corner an oil drain will be installed. It will be a small downward facing pipe that has a drain plug installed. This will be used to drain the oil from the oil loop when required.
In order to change the oil the trailer will be tilted slightly so the oil fill is at the highest point and the oil drain is at the lowest point. Both the oil fill and oil drain will be opened at allow the oil to flow out freely and then drip for a few minutes. Then the drain plug will be installed again and the new oil will be added using the oil fill.