The air valve leaking under the coach has N15759DG 70 147K MB USA stamped into it. I can't find it online, and anyway tomorrow morning I was planning to start driving 1,000 miles from Denver to Reno. What advice can I get on how I might find a replacement for this part between here and there? Or should I just be pulling into a roadside truckstop and asking whether they can repair this and any other air leaks they find? I don't mind paying someone else to do the repair, but who does this sort of thing?
Try looking at Haldex #KN31011 - Pressure Protection Valve see if thats the one.
jk
The original style protection valves are no longer made, but NOS ones can be found on ebay occasionally. The problem with NOS is they will be around 10, or more, years old, so the rubber diaphragm will be that old too.
I replaced ours with the, readily available, newer version. A direct replacement per Haldex:
Haldex 90555396 Air Pressure Protection Valve Black 65 x 70 PSI 1/4
Haldex Air Pressure Protection Valve Black 65 psi 1/4" NPT 90555396 | eBay (https://www.ebay.com/itm/274777849151?epid=1975213437&hash=item3ffa093d3f:g:4D4AAOSw0TNggilJ)
The replacement looks a bit different, works perfectly.
Greg
1. Try Google search for N15759DG. Lots of hits. FWIW, I answered this question 2 days ago in your other thread:
Air leak for beginners (https://www.foreforums.com/index.php?topic=42515.msg426191#msg426191)
2. I do not recommend this unless you have unlimited financial resources and a lot of time on your hands. Untrained mechanic trouble shooting unfamiliar air system at $150/hour equals $$$.