Air Leak

[DUG]

I traced my under dash air leak to the Low Air Pressure Buzzer Switch. It is leaking out of some sort of weep hole on the right side. Mine is a type A (209-20-3-1 pg 7-267). Any idea if it's repairable or where to get another?

The buzzer quit working today as well. I'm assuming because of the switch. If I mind my air pressure gauge before take off, can I cap the line to the Buzz Switch to fix the leak until I can make repairs?

 

[doghead]

Saturn Surplus and yes

 

[det45]

When I picked up my deuce, it had an air leak from exactly the same place. I removed it from the firewall, took it apart, and inspected all the parts. The two halves of the valve were just a little loose, allowing air to leak between the housing anf the diaphram. I put everthing back together and reinstalled, leak fixed. Haven't had any problems since.

 

[rat4spd]

JB Weld

 

[DUG]

Attached is a pic of the part and the whole where it's leaking. Nothing to take apart, no halves.

 

[crazyplowboy]

You can unscrew the plastic part on top (with the terminal coming out) from the metal body. There is a rubber diaphram inside with a brass center that moves up and down with the air pressure to control the buzzer.
When I got my Deuce I had the same leak. I took it apart, cleaned everything up a little, made sure that the diaphram was in it's place so it would seal the gaps when I tightened the top, snugged it back up and was good to go.

 

[DUG]

Thanks all! That fixed that! But I discovered another leak on top of the selector switch for the front drive. Not sure where, I'll have to pull it this week and look.

 

[ohnuts]

M35a2 Air leak back on the firewall under the dash. Worst part is the wires are starting to break apart on insulation when I popped the gage cluster loose. Anybody sell the wire harness for under the dash? The hoses I can have custom built.

 

[rosco]

The low air warning buzzer, besides the leak, is pretty important. On the most elementary inspection by DOT, they will most always check the low air buzzer, and will want it to come on right on at 60#.

Lee in Alaska

 

[DUG]

With the info from det45 and crazyplowboy, along with a kick in the rear from Rat4Spd, I cleaned it up enough to see where it threads together. Same story as the others - cleaned up, screwed it back together tight and now it works fine - no leaks. Buzzer is again being a loud PITA. I still have an under dash air leak from somewhere on top of the front drive engage lever. I need to drop it down and have a look. I'll keep chasing them down until I have them all plugged.

 

[Jake0147]

The low air warning buzzer, besides the leak, is pretty important. On the most elementary inspection by DOT, they will most always check the low air buzzer, and will want it to come on right on at 60#.

Lee in Alaska

They only check it because they see the air gauge or the glad hands. You don't need the buzzer or the gauge. UNLESS of course you have a trailer attached that is full air or air over hydraulic. Then you have to have both.
Although it's California, they might want you to run a new wire to both air tanks, the brake linings, the fuel tank, and every nut and bolt on the truck that might come loose. And there's probably a bylaw somewhere that you've got to upload a new ring tone into it to evoke the proper response that they'd like you to have when it does go off.

Forget the leak, forget the laws... The air buzzer is a safety system that should not be bypassed. If you're gonna wing it till a switch comes in, well that's not quite the same ball park, but it is winging it. DO NOT monitor the gauge at startup to tell you when it's fine to drive as was mentioned in the first post. That's the easy part. The hard part s that the gauge must be monitored constantly, as it does not tell you when you can drive, rather it will tell you when you need to stop driving immediately and find and correct the new trouble.

 

[DieselBob]

I still have an under dash air leak from somewhere on top of the front drive engage lever.

Mine was leaking at the fitting where the supply hose connected to the valve. The hose had what looked to be a reverse flair sort of like a brake fitting but it was attached directly to the valve that has NPT threads. Changed it out to a copper line with compression fittings. Not original but I had the parts on hand.

 

[DUG]

Pulled the front drive engage select switch and found it was cracked. I think the 1st leak was my only one until I started tightening stuff down. My bad. Anyone got a switch?

 

[ohnuts]

One step behind you dug. I've done so many I'm going to thread it.

 

[DUG]

Got the air leak fixed! She's been holding air for two days now vice 10 minutes. Dog Head sent me a brass (not plastic) Front Axle Engagement Switch and it cured the problem. Only thing now is he won't answer my PMs to tell me how much I owe him! I'll figure out a way to "get even". Thanks again DH!