I am getting ready to get my grapple hoses made. I know the size of the ports on the grapple valve and the cylinder. But, how do I know what size fittings to get put on the end that connects to the loader valve and what adapters are required to hook the return to the new valve?
There are three types of fittings most commonly used on tractors, they are NPT, ORB and JIC. Doing google searches of these will turn up all kinds of info and pictures. You may also need a way to accurately measure what you have so you can compare them to charts.
What tractor do you have? Asking others who have the same or similar machine may be able to help also.