ken graham

My Feedback: (10)

ok here is the question? how much air pressure should the system hold as for psi. i have yellow aircraft retracts, valves, lines and air tank also in the system i have installed bvm air gauges. I can only get 40 lbs of air pressure even if i hook a air compresser with 120 lbs of pressure. the gear will cycle only 3 times with such a low air pressure. do i need to worry?

HeliTB

Most retracts hold at 100psi for the small tank and up to 150psi for the large tank. Cut off point depends on whether they are air up/down or air up/spring down. If they are air up/down I would be extremely careful with low pressure.

F-16 Skywalker

what size is your air can,?
mine is only about 4 inches long and i have no gauges and use a hand pump and the gauge doesn't work in it either but I dont use the adapter on the hand pump(lost)
I just cram the hose into the air valve in the fuse and pump until the air line from the pump pops out from the pressure and I get about 6 cycles.

invertmast

My Feedback: (23)

I've got 2 large Robart air tanks on the YA F-18 twin gear. Those tanks hold 120psi of air easily and enough volume for 8-12 cycles.

ken graham

My Feedback: (10)

i have a extra robart large air tank will give that a try. they are air up/air down retracts. just can not understand with 120 psi from a air compresser it should be able to transfer that air pressure to the air system in the plane.

invertmast

My Feedback: (23)

Ken, i've got a small 1 gallon air compressor that i've attempted to fill mine up. It'll only get the system up to about 60psi then it calls it quits.. I then had to "hand pump" the system up to 120. i think i need a compressor that'll flow more air

USSCAT

I may be off base, but I believe the problem is really what the pump is rated for with the existing hose. Confused...let me explain. The pump may have a hose that is 1/4" ID and is rated at 120 psi, now what you are pumping in to is a line that is less than 1/8" Id. once the tank gets filled to a certain level the back pressure from the tank will limit pump input. That is the reason that you can use your hand pump with the same air line to pump up to the higher levels.

Regards,
Mike

ken graham

My Feedback: (10)

i see what you are saying i have a air compresser that is only 5 or so hp with a 25 gal tank. but i tried it with a robart hand held air pump with a gauge on it. at first i got right around 110 psi but after a few times of running the tank down by using the retracts i can only get around 40 lbs of pressure. i wonder if it's the hand pump it is around 4-5 years old but it's not used that much.[&o]

jedijingle

My Feedback: (45)

They dont work until about 40 psi. I would check for kinks in your lines or blockage. The YA gear works great. I pump my up to about 70-80 and can around 5 cycles on the gear. Once they get down around 40 they don't have quite enough presure to trust them. They hold air for days.

454

My Feedback: (9)

OK if you don't have a kinked line .
Dude your hand pump is worn out
and you air compressor will do it, I do it all the time ,I like doing it
you just have to have the proper connection

ken graham

My Feedback: (10)

i have to wait till i get home again to try acouple of things.