How do I find an air leak ?

[RETIDEPXE]

Moving around in the truck

When the air pressure's droppin don't bother knockin.....

My experience with my M2, 1st air leak was one of the AMU's above the rr axle. Take a 3ft L of 1/2" clear plastic tubing from Lowes or HD, against your ear on one end and the other end slide in the gap just behind the AMUs all in a row. Be sure your air is pressured up and if leaking, you will hear it and can measure distance to tell which one leaks. I believe I have found the fix for AMU issues, still no problems since about 550,000 mi.s ago. See my post towards bottom; http://www.expeditersonline.com/forum/truck-talk/52431-another-air-leak.html

Second, leaks showed up in the 45 degree plastic elbows and smaller pass thrus coming out of the brake air distributor block on the firewall, driver/engine side. Easy to find, pressure up, spray soapy water on them. Replaced with brass, any big truck dealer should have them.

Third, air spring pin holes, 1st in my Donvels (front axle), 2ndly in the bunk, then one rr axle air spring so far. Use soapy spray first to find holes, but the 1/2" tubing will work also, especially the harder to reach areas.

4th, the auto leveler switch for the bunk air springs cycles too much air while driving (too sensetive) as far as I'm concerned so I bypassed the leveler and bought another manual air switch and gauge from Donvel (mainly because Donvel is 30 mi.s from my house and they are good people) and keep the bunk springs pumped up manually. In doing so, my air pump, while at a steady hwy speed, went from cycling every 15 to 25 minutes to cycling only 1 to 2 hours now, probably because of the rr suspension bags.

BTW, the soapy water is a must in my arsenal of tools. Great for checking charge air cooler leaks around the clamps.

Good luck.

 

[jimby82]

Don't forget the sleeper air ride air bags is so equipped. Our truck was doing the same as you described. Finally hole in one bag grew large enough to hear. Replaced bags, problem solved (at least for now) Good luck!

 

[ATeam]

We just had an air leak repaired. On the Volvo, there is a junction box through which air lines pass through the firewall. The O-rings behind the quick connect air line connectors got old and brittle. A lot of shops would have replaced the box which would have been a four hour job plus the cost of the box. Our good people at VoMac in Fort Wayne (New Haven), did the O-rings instead for a fraction of the cost.

Air leaks like the kind you describe are difficult to find. The first thing to find is a quiet place where small, nearly-silent leaks can be heard.

 

[zorry]

I bought my first two Volvo's in Frt Wayne.
I once pulled into a shop in Mi on second shift. The mechanic put a regulator in the dash in 15 minutes.
He brought his time ticket in "job completed" before I was written up.
Overall, I don't believe anybody's got a better dealer network.

 

[ChanceMaster]

We just had an air leak repaired. On the Volvo, there is a junction box through which air lines pass through the firewall. The O-rings behind the quick connect air line connectors got old and brittle. A lot of shops would have replaced the box which would have been a four hour job plus the cost of the box. Our good people at VoMac in Fort Wayne (New Haven), did the O-rings instead for a fraction of the cost.

Air leaks like the kind you describe are difficult to find. The first thing to find is a quiet place where small, nearly-silent leaks can be heard.

I've seen that junction box on the FL wall. Good advice. Thanks.

Sent from my PC36100 using EO Forums

 

[Deville]

In the past year I replaces the tractor brake valve that blew out & the airbag air dump switch. These usually start off as small problems & become big annoying problems in a hurry.'

Check your air seats to. They see alot of movement, the lines could get worn out over time.