Todds Models

I am building an Xtreme Jets BD5 and the nose gear retract is leaking air. When the gear is in the down and locked position it is fine but when it retracts all the air bleeds out rather quickly.

So what it looks like is a fitting on top the cylinder and a fitting at the bottom of the cylinder where the piston rod comes out.

When I apply air to the botton fitting the gear will come down and hold air.

When I apply air to the top fitting the retract will go up but not lock, if I take the line off the bottom fitting I can feel the air comng out. So it seems air is going by the piston inside rather easily not allowing the full travel.

Any help I can get would be appreciated.

Thanks in advance.

Todds Models

Just took it apart and it is probably a bad o-ring. Going to see if I can find one the right size.

What is the correct lube used for the o-ring in retracts?

bcovish

My Feedback: (8)

You can get silicone o-ring lube at dive shops. Get "Parker o-ring lube' if you can find it. BVM sells it also.

Todds Models

Any idea where I can get a new o-ring? Tried 3 different places and 1/2" is too big and 7/16" is too small....

bcovish

My Feedback: (8)

Could be metric

Johnny Isaiah Woods

My Feedback: (81)

Rocket Seals will have what you need, they are located in Denver, Co.
Google them for the contact information.

Johnny

invertmast

My Feedback: (23)

Granger or mc-master carr would probably have it as well. I vaguely remember hearing of some wrapping teflon tape in the center of the piston groove to get a standard size o-ring to fit

Shaun Evans

Hi,

I hope while you're doing all these remedies, you also get them to give you a working unit.

rolsen12

Try a bearing supply house, the might have the one you need. Take the old one with you.

Todds Models

Yup, sent an email to BVM and Xtreme Jets but its the weekend. Will finish the Stingray after this jet.

bluescoobydoo

if it is new send it back you paid good money for it i should work.

bcovish

My Feedback: (8)

[8D]

Craig B.

I have resorted to this and it works really well. Only usually requires a couple of winds to increase the squish on the o-ring. I have seen some retracts where the o-ring recess in the piston is just the wrong size and it still leaks even if you have a new o-ring in there. That's where the teflon tape can help you, and the silicon grease from the dive shop. I also use 80 wt silicon car shock oil from the hobby shop to lube up the retracts...works well.

Craig.

sidgates

My Feedback: (2)

I second the recommendation of Rocket Seals. They have had every "O" I have every needed in stock.

rhklenke

My Feedback: (24)

Yep, this method works great. There are details and pictures here:

http://www.rcuniverse.com/forum/fb.asp?m=8042800

http://www.rcuniverse.com/forum/fb.asp?m=8067703

http://www.rcuniverse.com/forum/fb.asp?m=8305981


I have yet to build a Chineese ARF where this method wasn't necessary to keep the O rings on the retract cylinders from leaking (granted I have not done a YA ARF...), so I just do it now from the start.

Bob

Todds Models

Thanks for the help guys. I ended up putting Teflon tape on all three pistons under the o-rings. Retracts now go up and down.