Best way to find air leaks

[Doffer 3]

I have an annoying air leak on my 2001 mack RD688S Cab-Over pump truck. The Secondary tank is holding air, but the primary is leaking off when sitting overnight. Can i dump some UV Dye into the tank and wait for it to leak off then check all the air lines with a UV light, or will the UV dye hurt something?

Edited February 9, 2013 by Doffer

[2stacksuperdog 4,114]

That is a new way of doing it.

[Doffer 3]

That is a new way of doing it.

do you think that would work pretty good?

[2stacksuperdog 4,114]

Only way to find out is try it right?

[Doffer 3]

I'll try it out and report back

[theakerstwo 766]

get a grand son out there and they can hear it if they close their mouth.

[jakebrake86 438]

My only concern would be clogging up valves and what not, but if it's safe in a/c systems I don't see why it wouldn't be cool in air systems as well. I've got a couple of pesky air leaks I've been tracking down on my RD, too. Sometimes if I can track it down to a somewhat certain spot, I'll spray a little soapy water on it to pinpoint where it is. I think a couple of years of running open cab TS 14 Euclid scrapers with twin 471 green leaker screamin demons has forever limited my air leak finding abilities by hearing alone. LOL

[Dougsr 56]

i used to use kids bubbles to find leaks on the big AC systems when I worked offshore. You could put it in a spray bottle. You can buy it by the gallon. That is what i did.

Doug

[220cummins 291]

Murphys oil soap has been the go to for leaks

[realwolfdaddy 14]

Find a large tub or water and submerse the truck and look for where the bubbles come from. LOL! Seriously soapy spray works best for me.

[rsb502 1,679]

I just use a little dish soap mixed with water in a spray bottle to find air leaks, as far as UV dye goes an air brake system ain't quite like an a/c system there is quite a pressure difference and a/c systems are made to circulate oil and the die goes runs with the oil. Air brake systems are not happy about fluids and the dryer will more than likely catch it all if you put it in before it and in the large air tanks it will drop to the bottom and sit at the drain. Truck air tanks are made with the air fittings above the 50% line to keep moisture out of the lines and in the tank to be drained.

[cl733 0]

mix up a bucket of soapy water, get a broom handle and tape a piece of 3/8 clear hose to it , suck up some soapy water using your mouth on the hose, use the stick to reach into spots, like under the cab, and hard spots to reach , and blow some soapy water on your connections , watch for bubbles, its worked for me trying to reach under the cab and hard to reach places,

[Stick-man 0]

First, go where it's as quiet as possible, and use your ears. Then, follow the lines from the primary tankand spray every connection with dollar store dish soap and water, heavy on the soap. Some, you can't hear until you're right up on it. But the soap will tell everything.

[Samogen 0]

Spray bottle with soapy water is a universal leak finder tool. It doesn't  work for inner leaks  though like valves. Air preasure monometer with hose couplings works just fine to find such leaks.

[BOB DINGSDALE 181]

is there a one way check valve between compressor and primary tank.If not your valves in compressor could be leaking back. Something you would never hear. If you havn't got one in line get one and try it.

[tenfive0 31]

 

[blackdog2 381]

hook up shop air  shut truck off chock wheels put in gear take key out >