PSA: Check your fittings

[wandering neurons]

I found that the pressure protection valve from the wet tank on my M1081 was leaking where the two halves are assembled. No gasket in there. Made a gasket and was reassembling the entire christmas tree of fittings in prep for reinstallation onto the right angle fitting on the tank. I noticed something odd on the adapter that fits to the right angle fitting - a crack. Either someone overtorqued the fitting during assembly, or stress from bouncing around supporting the rest of the connections, but something cracked the fitting completely.


(vertical line in the back of the fitting. best that smartphone will do)

I assembled a new christmas tree of fittings using a new valve from NAPA. Their replacement for the KN31000 is a 90555396. Same pressures, but only 1/4" fittings on either end, not the 1/2" fittings. I can't find a valve with 1/2" fittings anywhere, so put together a bunch of adapters to make it fit. My bigger concern is that it won't support the same volume of air as the original valve.

Will see if a gasket will fix the leak in the old valve, and see if the fitting is a regular part somewhere.

But in the meantime, check the adapter just off the right angle on your wet tank...

 

[Awesomeness]

Let us know how it goes. Going 1/2" to 1/4" sounds bad enough on the surface ("Wow, 1/2 the size!"), but it's actually only 1/4 the cross section. That would make me nervous too.

 

[wandering neurons]

Let us know how it goes. Going 1/2" to 1/4" sounds bad enough on the surface ("Wow, 1/2 the size!"), but it's actually only 1/4 the cross section. That would make me nervous too.

In thinking about it, the valve itself has some pretty small holes inside under the diaphragm. IIRC, it's primarily servicing the CTIS, so it may mean slower filling tires. And the lines coming out of the valve are pretty small too. So it's probably a problem of volume, which may not be too bad. Will see and report, if I can get my CTIS to quit flashing five red lights...