spring air retract help in my GP-F14
#1
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spring air retract help in my GP-F14
help please , I am use to building warbirds and usieng sierra , CJ and robart gear . This is my first set of spring air retracts and I cant seem to get them to work . Ok --first the "I told you so " I bought them on ebay from a reputal seller , they seem to cycle fine after I upgraded to a new spring air switch , and a robart air valve .
SO i get them installed and now it seems that the tank is so difficult to pump up --as it its filled yet it wont cycel the gear (small tank--came with the gear )
any help please-- also the nose gear cycles less then the two gear legs in aft part of the fuse ????
SO i get them installed and now it seems that the tank is so difficult to pump up --as it its filled yet it wont cycel the gear (small tank--came with the gear )
any help please-- also the nose gear cycles less then the two gear legs in aft part of the fuse ????
#4
RE: spring air retract help in my GP-F14
i purchased a new set with a plane kit of off of ebay and have asked them a couple of questions with no problems. i love these retracts. i will order more when new projects are under way.
david
david
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RE: spring air retract help in my GP-F14
LDM
I must have 30 E-Bay retracts in the cabinet of all makes and sizes, and ages. Each one works well regardless of age, there is little to go wrong. OK, go down to your Hardware store and find some Hydraulic oil, thin around 10w if available. Air tool oil also work fine, something I have been using for some time. Remove line from the retract yor working on. Get out pump and line, suck up about 1/2' to 3/4" inch oil into pump line, attach to retract and inject and cycle a few times. Retract should loosen up well and work with ease. If not, redo oil and cycle. If still slow, apply little 3-1 oil to your shaft bearings and work in. If still sticky, you have a bent gear or shaft. Send in to robarts for repair, will be cheaper than buying part after part. Don't use any other oil than air tool or hydraulic oil in the cylenders or valves as it will swell up the o rings and freeze things up. All decent shape mechanical or air retracts should operate with very little hand/air purssure. If not, fix them prior to flight or you will pay dearly for the neglect. Your system should hold air with no loss for 20 minutes. If not, check valve, T's and ram shaft and line connection for a air leak, you have one, and must must fix it pryor to flying. Holding up to 5 minutes or 10 just does not get it. Mine still operate after sitting overnight, and are also used. Plastic connectors and T''s including ram connection are usual culprit. Check for leaks with gear both up and down. Tank size. You should get 4 cycles out of your tank size for safety backup. Spend the money and buy the adjustable valve so you can adjust the speed of retracting action. At 100 psi, you can punch a hole through your wing skin from closing action. You want it possitive, but not slamming things home. A brisk closing is good. A wham is gonna break something sometime and is hard on your mounts and gear. Being hard on your mounts is not a good thing. Have seen them close so hard the gear body bends or breaks, you don't want that. Yes, you can use a wheel collar and adjust the air pressure. It will eventually cause a failure, takeing off or landing with the gear not locked down is tough on that $400.00 arf, prop and engine. A little TLC is priceless. ENJOY
I must have 30 E-Bay retracts in the cabinet of all makes and sizes, and ages. Each one works well regardless of age, there is little to go wrong. OK, go down to your Hardware store and find some Hydraulic oil, thin around 10w if available. Air tool oil also work fine, something I have been using for some time. Remove line from the retract yor working on. Get out pump and line, suck up about 1/2' to 3/4" inch oil into pump line, attach to retract and inject and cycle a few times. Retract should loosen up well and work with ease. If not, redo oil and cycle. If still slow, apply little 3-1 oil to your shaft bearings and work in. If still sticky, you have a bent gear or shaft. Send in to robarts for repair, will be cheaper than buying part after part. Don't use any other oil than air tool or hydraulic oil in the cylenders or valves as it will swell up the o rings and freeze things up. All decent shape mechanical or air retracts should operate with very little hand/air purssure. If not, fix them prior to flight or you will pay dearly for the neglect. Your system should hold air with no loss for 20 minutes. If not, check valve, T's and ram shaft and line connection for a air leak, you have one, and must must fix it pryor to flying. Holding up to 5 minutes or 10 just does not get it. Mine still operate after sitting overnight, and are also used. Plastic connectors and T''s including ram connection are usual culprit. Check for leaks with gear both up and down. Tank size. You should get 4 cycles out of your tank size for safety backup. Spend the money and buy the adjustable valve so you can adjust the speed of retracting action. At 100 psi, you can punch a hole through your wing skin from closing action. You want it possitive, but not slamming things home. A brisk closing is good. A wham is gonna break something sometime and is hard on your mounts and gear. Being hard on your mounts is not a good thing. Have seen them close so hard the gear body bends or breaks, you don't want that. Yes, you can use a wheel collar and adjust the air pressure. It will eventually cause a failure, takeing off or landing with the gear not locked down is tough on that $400.00 arf, prop and engine. A little TLC is priceless. ENJOY
#7
Thread Starter
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RE: spring air retract help in my GP-F14
Thanks guys , let me be specific , I had the gear installed , but the tank and airintake valve were not installed yet , it was all in the test mode .Then I installed it in its most appropriate location . When I try to fill the tank (smaller Spring air version ) not the bigger 100 psi robart tank , its very difficult for the air to enter the tank , its as if the tank is full ???
My robart pump measure that I am putting in a good 40 or so psi with every attempt but its drops to zero immeditly adter each pump .
Now remember , I am newbee to spring air , not retracts , in fact I have over 14 sets in variuos WW2 birds with no flaws at all .
I am thinking that my problem starts with the filler valve , then if thats not it , its the tank , then I check the t-connectors and so on and so on .
I like the ideal of the air tool oil , but so I understand you correctly am I putting the air tool oil in the actual lines themselves ???
I did use oil on all moveing parts , that did help prior to my final instalation .
SO remember my # 1 issues right now seems to be filling the tank , I know it should not be as hard as it feels on each pump
My robart pump measure that I am putting in a good 40 or so psi with every attempt but its drops to zero immeditly adter each pump .
Now remember , I am newbee to spring air , not retracts , in fact I have over 14 sets in variuos WW2 birds with no flaws at all .
I am thinking that my problem starts with the filler valve , then if thats not it , its the tank , then I check the t-connectors and so on and so on .
I like the ideal of the air tool oil , but so I understand you correctly am I putting the air tool oil in the actual lines themselves ???
I did use oil on all moveing parts , that did help prior to my final instalation .
SO remember my # 1 issues right now seems to be filling the tank , I know it should not be as hard as it feels on each pump
#8
My Feedback: (540)
RE: spring air retract help in my GP-F14
ORIGINAL: LDM
......... they seem to cycle fine after I upgraded to a new spring air switch , and a robart air valve .
SO i get them installed and now it seems that the tank is so difficult to pump up --as it its filled yet it wont cycel the gear ......
......... they seem to cycle fine after I upgraded to a new spring air switch , and a robart air valve .
SO i get them installed and now it seems that the tank is so difficult to pump up --as it its filled yet it wont cycel the gear ......
I think you have the old two part fill chuck... a check valve and fill port. if check valve is reversed then you will think tank is full when your system has no air at all. a pressure gage will let you know hook it up to the air tank with TEE
new robart has an one piece "schrader valve" just like a car tire.
bob
#9
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RE: spring air retract help in my GP-F14
Bob , you take the cake , I traded out the valve in my parts box for another , it was not backwards but it was bad . Now the tank pressurizes just fine and gear cycles . Now I my only last issue is a simple fix of the nose gear push rod wanting to turn and bind as it retracts . I think that will solved when the rod has tension on it from being locked into the steering servo , because I dont have it locked in , it can actully extend on retraction and bind .
Everyone , thanks for the help and support , remke , its not the $400 arf , its the Great Planes F14 kit , I am making many mods from servo position changes , and ensuring lateral balance , and I want to add gear doors with my retracts . I have not built a kit in a long time , so I guess I going to tinker before I can call thie finished
Everyone , thanks for the help and support , remke , its not the $400 arf , its the Great Planes F14 kit , I am making many mods from servo position changes , and ensuring lateral balance , and I want to add gear doors with my retracts . I have not built a kit in a long time , so I guess I going to tinker before I can call thie finished
#10
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RE: spring air retract help in my GP-F14
Ok added the struts , my olly problem now is a small leak , I am losing air somewhere in about 5 miniutes , I think I need a check valve between the filler valve and tank , air is now going in fine , the gear is pressurized but it leaks out slowly