830 CK auxiliary valve

It depends on your valve how difficult it will be to put it together (they used at least 3 different aux valves on the 830). One of the heads on mine had a couple of 1/4" ball valves which would fall out of their seats and down into the passages if the head was tilted. Later ones, I think had a thermal valve in the right head with one ball. To get mine back together, I ended up having to balance the larger check balls on their springs and lower the body ONTO the head. If you can keep all the balls stuck in place while you put it back together (maybe some thick grease that's compatible with hytrans?), it should be possible to replace just the gasket and O-rings without unmounting the main valve body. You shouldn't even have to remove the swivels or hoses . Just remember if you do, that there are springs and check balls under the swivels that can get away.