Question on HD16DC brake valve plumbing

Hello Friends

A question that has had me wondering for a while now and just getting around to asking for opinions.

At the rear of my HD16DC looking at the two brake operating valves, the left side unit has a different hook up than the right and one that I cannot find in my original Operators, Parts or Service manuals that came with my tractor. Only the left side is hooked up this way and I'm wondering why as it does not appear to be original to the tractor and no manual bears it out. One of you may know whey this was done and I would really like to know your thoughts. Pics are below.

Thank you everyone.





Thank you again.

CAL(KS) wrote: looks like a homebrew system to either vent both areas with the same breather or allow excess oil in the brake cylinder area to bleed back into clutch housing while still allowing said housing to be vented

Thank you Cal. The right side does not have this and just has a steel plug in the housing. Would there be any benefit to this as on the surface I cannot see any. It's not stock and only one one side. Thinking of taking it out and see what it does.

My 7G has housing breathers as that, someone did a pretty good re-engineer project there to vent the systems. Rubber lines would have worked as well or just adding another breather cap.

Thanks everyone. Good ideas and points. I will likely add vents to both holes .

DMiller wrote: Another Minnpar parts book scan shows breathers at BOTH holes both sides. May have been knocked off in the past backing into something. Pages 172 and 210.

Thank you DMiller for the reference. I looked it up and found that based on wether its a HD16 manual or HD16DC manual you get different pics on this. On the DC version it is showing breathers on the steering clutch as well as the final drive housing. I can't see the harm in adding the breathers rather than my copper snake method.

By the way, I put that copper line in as the one that was on the tractor when I bought it was cracked at the fitting and it was hard copper that was bent using a pipe bender. One solid piece and nicely done. I didn't have a pipe bender at the time so I soldered the pieces to get it done. Pretty janky looking I know but Im going to lose it and put on breathers for the final drive housings which is what I think the previous owners were trying to do.

thanks again everyone.