stunthanger.com
Speed,Combat,Scale,Racing => Combat => Topic started by: Bob Furr on January 17, 2011, 04:57:48 PM
-
Okay... which OS remote needle is best for bladder pressure systems? I seem to remember comments about the OS 10 but the curse of getting old is keeping all those memories sorted out!
Bob Furr
-
Bob, hopefully some experts will respond , but i believe it is the one marked 1A.
-
We use the OS 1A needle valve, part number 21181902.
-Chris
-
Well... I hope I can make use of what I just bought. I found OS10 needle valve assemblies on EBay that I went ahead and bought they are not the remote assembly but the version that was screwed direct into the RC carb. Looks like they will work with maybe a little fussing. If not I will put the back on the bay for someone who needs parts for their OS.
Bob
-
I think you will find that the remote needles are the ones that thread into the carb.You just need to devise a holder for them.
Brad
-
One way to do it is to use an aluminum triangle off the engine mounting bolts.
Everyone has there own favorite way, for example off the back plate or off a little L bracket from the center rib.
-Chris
ps. As Brad said, the one commonly used is the one that screws into the r/c carb, but is convertible to remote mount with a bracket.
-
http://www3.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=21181902&search=Go
this one works, is use a cut down nylon control horn to mount it and plumb it the other way, some old timer told me it won't plug up as often.
-
I have soldered brass tubing barbs ( http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWH38 ) to the spout that screws into the R/C carb. A large slider type line clip will work as a mounting.
-
Dave mentioned plumbing it the other way, which I think means fuel goes in the nozzle end (no barb to start) and out the right angle tube (with the barb). That is actually supposed to be better since the fuel pressure hits the needle and seat first, then lower pressure hits the outlet tube and needle threads. This means fuel is less likely to leak out the needle threads. I wasn't adding a barb to the nozzle, so the pressure would cause the tube to come off in flight.
-Chris
-
Chuckling.... well the tower price makes me feel much better about what I bought... so I need to do something to keep the fuel line on the nozzle side? Bob
-
Hi Bob
If the nozzle is towards the bladder (high pressure) side, the fuel line will slide off unless you do something to help it stay on. The nozzle is just too small in diameter. Soldering on a fuel barb is one way to fix the problem. I have also seen a piece of copper tube pressed onto the nozzle to increase its diameter.
-Chris
-
We've been using OS 10 and 15 needles both ways for years, both ways work equally well as long as you use med. fuel tubing not large, just attach it with a line clip and off you go,I've been doing it this way trouble free for more than 25 years.