Yong Heng problem. ANY IDEAS/SUGGESTIONS?

[Gerry52]

After 3+ years I'm having my 1st major problem with my YH. It WILL NOT fill past 3500psi. I checked EVERY fitting & filter, foster connections, seals & o-rings where I could have a leak. Absolutely ZERO leaks. I put together a "dead head" fitting that ends in a pressure gauge. Compressor EASILY fills all my lines & filters to 4500psi but when I go to fill my tank the Compressor gauge & secondary gauge on my tank fill adapter WILL NOT pump past 3500psi! The needles on the compressor gauge, fill adapter gauge & tank gauge just sit at 3500psi & go no higher Doesn't make logical sense to me. Any ideas?

 

[Franklink]

Maybe leaking from the bleed on the fill station on the tank end?

Like the bleed isn't closed quite tight enough?

 

[Franklink]

Had a similar problem in the last few days and figured out something had let loose inside the Yong Heng gauge. So it was leaking from the gauge.

I just plugged that hole since the gauge never read correctly anyway.

 

[Long_Gun_Dallas]

It definitely is leaking somewhere. Those slight high pressure leaks can be hard to locate.

 

[Stubbers]

I'd go around with a moist finger checking for leaks then confirm with soapy water, if that doesn't point in any direction, repeat with just soapy water, lastly if that doesn't work, try the dunk test (this is a joke, don't dunk your entire YH compressor into water while running, dunk it in mineral oil (joking again)).

If a leak isn't found externally I believe the most common place next would be one of the piston orings.

-Matt

 

[Gerry52]

I checked EVERY SINGLE place externally where there is a possibility of leaking with spray of soapy water. It's NOT a typical pressure leak. It just will not put more than 3500psi into the tank. If a dead head test will go to 4500psi why won't it fill TANK past 3500psi? No, it's not the tank gauge reading incorrectly as there are 2 other gauges on the outgoing pressure line that correspond to the 3500psi reading. It shows NO EXTERNAL LEAKS at all! Not a single bubble from the soap/water spray. WTF? The dead head test tells me it's capable of building over 4K psi of pressure but it won't put it into tank.

 

[Gerry52]

Maybe leaking from the bleed on the fill station on the tank end?

Like the bleed isn't closed quite tight enough?

Nope

 

[Stubbers]

That is strange if it passes dead head test.....BUT, it's simply a matter of work over time, where a dead head takes no time to build pressure, a big tank does, and a small leak will impede this.

 

[Stubbers]

Have an hour meter? If so how many hours on this YH?

 

[DBlue]

Try filling a gun with it.........

 

[Stubbers]

Size of cylinder changes the fill rate which...small leaks will outpace at a certain psi where the vent (leak) is greater than the rate its able to fill the cylinder, confirming with the dead head and/or smaller cylinders won't do much to help find the leak imo.

-Matt

 

[Heavyopp]

Have you tried the dead head after the YH gets to whatever your operating temp is?

 

[Scotty1]

Have you filled your fill set with the tank valve closed? Will it reach pressure while connected to the bottle with the bottle valve closed? Same question twice…

 

[Gerry52]

Have you filled your fill set with the tank valve closed? Will it reach pressure while connected to the bottle with the bottle valve closed? Same question twice…

Yes. It builds 4K+ pressure in in everything, then I open tank valve & all needles stay at 3500 for 10 minutes run time with no rise. Is that weird or what?

 

[Franklink]

Yes. It builds 4K+ pressure in in everything, then I open tank valve & all needles stay at 3500 for 10 minutes run time with no rise. Is that weird or what?

Yes, weird.

Somebody shared a while back that they had a leaky SCBA tank. It obviously hadn't exploded, but the aluminum vessel inside the carbon fiber had corroded through and the tank was leaking through the carbon fiber. The tank youre filling is holding air?

 

[Revoman]

Gerry!
I had a similar issue with my Shoebox and it turned out to be the regulated check valve in my moisture filter. It had bent a small piece that wouldn't allow enough flow to get to the tank (I'm assuming that your deadhead doesn't include your filter?).
Might have to open your filter up and check that valve if it has one.
mike

 

[Gerry52]

Yes, weird.

Somebody shared a while back that they had a leaky SCBA tank. It obviously hadn't exploded, but the aluminum vessel inside the carbon fiber had corroded through and the tank was leaking through the carbon fiber. The tank youre filling is holding air?

Tank has stayed at 3500psi for 4 days now while this is going on. I'll try filling while tank is submerged. There's a 3500psi threshold SOMEWHERE that can't be overcome for SOME reason. Over 30 years of experience with SCBA tanks & their accompanying maintenance & I've never seen this before.

 

[Franklink]

Tank has stayed at 3500psi for 4 days now while this is going on. I'll try filling while tank is submerged. There's a 3500psi threshold SOMEWHERE that can't be overcome for SOME reason. Over 30 years of experience with SCBA tanks & their accompanying maintenance & I've never seen this before.

I wasn't meaning to imply that you're inexperienced, just trying to help with the problem. It's sure a head scratcher.

 

[Franklink]

If you haven't already, hook everything up and pressurize the lines between Yong Heng and tank, with tank valve shut. Then turn it all off while still pressurized and see if you can hear a leak somewhere.

 

[Gerry52]

Gerry!
I had a similar issue with my Shoebox and it turned out to be the regulated check valve in my moisture filter. It had bent a small piece that wouldn't allow enough flow to get to the tank (I'm assuming that your deadhead doesn't include your filter?).
Might have to open your filter up and check that valve if it has one.
mike

Mike, yes dead head was at END of fill whips & all filters, no leaks. Goin to pull one way check on my tank fill assembly & replace with a new one & see what happens.