Here is a nitrogen filler port on a LG strut. it has schrader valve threads, but there is no stem inside, and when I apply nitrogen pressure (per the POH), nothing happens; I don't hear nitrogen flowing. the required pressure is ~180psi.

does the strut need to be unloaded prior to filling?

what am i missing?

I have a similar port on the O2 bottle filler (different plane), and the pressure does blow it in (it squeaks pretty loudly as it flows); but that's 1800psi.

I have never used something like that, but just looking at I bet you have to turn that nut counter clock wise while the nitrogen hose is connected to allow the nitrogen to flow in.

Isn’t that a normal Schroeder valve? Did you crack it open after applying the nitrogen?

That looks like the nitrogen port on my TBM. It requires unscrewing the hex nut to open the valve. You want to use a fitting that screws onto it and seals.

I use this: https://www.mcmaster.com/catalog/129/353/3534N3

nailed it. i bought that fitting. i'll try it as you describe. thank you!

Suggest you clean out the fitting first. Any grit or dirt in there will be pushed into your strut where it will do nothing good for you. It can even cause the fitting not to close properly leading to slow leak. If the grit damages the fitting sealing surface, the leak can continue even after the grit is gone.

Once clean, then you can do the refill. Then I suggest you put a cap on it, a proper metal aerospace qualified cap like MS20813-1B, which can hold high pressure.

I would have expected there to be a cap on the fitting and maybe it got lost. The cap will keep the fitting clean.

Also, I'd recommend reading the maintenance manual to be sure you follow the procedure. There are plenty of possible ways to do this wrong. For example, maybe this valve is only for draining the fluid, not for topping off the gas. Assumptions can get your into trouble.

BTW, use the above cap for your tires. It has an o-ring in it to serve as a backup for the schrader valve should that fail. Little plastic caps won't do that.

Mike C.

all good points. It had one of those caps, which i removed for the picture. it is a gas service port, and is placarded as such.

I also keep those on the tires.

nailed it. i bought that fitting. i'll try it as you describe. thank you!