I have a project 316onan that I am converting to diesel. Will post with pictures as it comes along..
BUT, as to this post.....
The 316 onan has only one hydraulic circuit. I want to add a second circuit. I was looking at the controller (spool valve) in my tractor. It LOOKS like a 2 circuit valve where one circuit is not hooked up. There are screw in plugs in the housing where a second set of hydraulic lines would screw in. There is a second plunger sticking out of the end (where the control handle attaches to) JUST LIKE the one hooked up to the working circuit on the 316 - just not hooked up to anything. It also looks like there is a plug for power beyond in the housing.
I would think that a single circuit valve would not have these extra parts visible. Can someone look at their 316 onan and see if their spool valve looks like what I described.
If this is what it is supposed to look like, is the spool valve functional if hooked up? If I add a control lever and fittings/lines would it work as-is? Or do they use the double circuit housing but the second circuit "guts" are not installed? Could they be?
This tractor came in a box, so I am not 100% sure this is the original valve. But the second circuit was not hooked up - why go to the trouble of installing it if you were not going to use it??????
I already have a replacement 2 circuit spool valve, second handle, lines and fittings to upgrade, so this is more a question of curious than necessity.....
I am converting the tractor to power steering, so removing the manual steering gearbox will give me more room for all the plumbing.