Phantom leaks

Alright, I've bagged quite a few vehicles and never had a leak that we couldnt find, and never let a truck go that leaked down overnight. But i got a truck at the shop right now that is totally mind f*cking me so I'm looking for some ideas.

Here's the deal:8 3/8" SMC7 gal Tank2 Viair 480s

Tank loses PSI. At first, the front holds air. At one point the front right was actually gaining air (very slowly). Then the next morning the front right was aired out completely. I have gone over the entire system a stupid amount of times with soapy water. i've ripped apart the front suspension to check the bag fittings. I have changed fittings that I didn't like the look of, even though they weren't visibly leaking.

One theory I have is that there is something messed up in a valve diaphragm on the front right. I think that maybe the tank is losing psi through that fill valve, which would also cause that corner to raise if the higher tank psi was allowed to leak to the bag. Then once the tank psi drops below the bag psi, that corner leaks down. I don't know if this is a reasonable theory or not.

The front also held steady at 80 psi yesterday for 4 hours. Then this morning it was aired out. I'm losing my mind.

its the smc's. my dumps would stick becuz they used to be the fills and would stick open. probably have either a tear in teh diaphram or its warped. i would tear the valves apart or replace them. what pressure are you guys running it to?

running the 480s on the supplied 165-200 switch.

all the valves are brand new. I have a couple more that i might swap in today but I think they are an older style so my tapped holes arent gonna line up for the brackets anymore.

put a reducer on your dumps and hook em to a gauge then leave it up all night.... if it leaks down and your showing pressure its a valve... if it dont you got a problem elsewhere

good call. I just got an IM saying to try a balloon on the dump valve too but I think I have more old gauges around then i do balloons.

lol guess a condom would work to for that matter... and im sure you can find those in about any minitrucker's glove box

I'm glad this thread came across, my front passanger leaks out within 1 to 2 hours. Soapy watered ecerything and couldn't find a leak. You're not alone Joel.

i havent rubbered up in years. haha. i wouldnt even trust the ones I have stashed away to find an air leak.

another think to check is if your whole tank is losing pressure you could have a bad check valve on a leader hose letting it blow back by the compressor... that's killed me a couple times

yeah, i sprayed down the comps as well to see if it was leaking through the heads. I've dealt with bunk ones before but these are brand new comps so hopefully thats not the problem