Is it possible to convert an older OS Max fp25 to a remote needle valve?
I just became a fan of them this evening.
I was adjusting the needle valve for one last flight for the night and managed to tangle three fingers of my right hand in the prop at full RPM.
Sliced through the fingernail on my index finger and it cut to the bone on the birdie finger. The other finger was sliced right across a scar where it was reattached after a junior high shop accident with a band saw about 26 yeas ago.
I have an fp 40 to retrofit to.

Hi Pa-18cub150

Go to http://www.towerhobbies.com/ and type in remote needle at their search box. There is also a Tower Hobbies icon at the top left of this page. This will pull up everything they carry in remote needle valve engines and parts. Basically the conversion kit is a needle valve assembly, a short piece of fuel tubing, a bracket to bolt the assembly to the rear backplate of the engine and a plug to seal off the opening from the old needle valve.

Dale

I love the remote needle valves on the OS engines, but what I hate is the first engines that came out with them had the needle valve housing cast as part of the backplate of the engine. Any crash will break the needle valve off and require buying a new backplate. I tried to fix them but never found anything that worked well. On the 46 AX they got it right and made the mount a small piece of metal that could be bent back in shape, or reproduced quickly in the event of a crash.

Ken

The Tower remote needle works very well and is more cost effective than a OS set up.

Just open up the original needle an extra amount. Mount you new needle on the rear. You don't adjust the front needle anymore.

Repairing the remote needle valve is relatively simple.

1st, THOROUGHLY clean all the metal in the area. I use several applications of acetone wiping it with a clean rag each time.

2nd. Depending on how it is broken, drill a small hole in each piece and insert a piece of 1/32" music wire into both halves (for strength ) and JB Weld in place. If it is not feasable to drill for the wire, take a piece of 1/4" (or smaller if needed ) brass flat stock and bend a "C" to fit snugly over/around the broken parts and JB Weld (again, for strength ).

Use the regular JB Weld, not the quick stuff - the regular is substantially stronger.

I have repaired several OS 46 FX (mine and other peoples ) like this and out of 8 repairs I only had one fail. I think the one that failed was due to me not getting it clean enough before JB Weld it. It doesn't look that pretty, but it works and is cheaper than a new backplate.

Campy,
Yes, I did all of those for repairing them. But I just wasn't happy with the results. The JB weld failed, so I just bought another backplate to replace the broken one. I recently picked up a box of "non-running" motor at a swap meet, so I have replacement parts now to spare.

Ken

I have the exact same engine you do. This is the kit you need and it works Great, well worth the $7.99 to not get your fingers diced.
http://www2.towerhobbies.com/cgi-bin...?&I=LXCC27&P=7

This is exactly what I am looking for.

Out of this I have learned three things:

1 never reach over the prop always reach from behind or from the side

2 remote needle valves and remote glow plugs are a good idea

3 A first aid kit is a must have item

We all make mistakes, it is whether learn from them that is really important.

I have talked to three people who have don the same thing. If it was going to happen I’m glad it was with a small engine.

I have a us engines 41 I am putting in a Dynaflite 104" Super Cub. Dose anyone know
if there is a remote needl valve assy. for the U S 41?
Thanks
Mike

The US 41 is unlikely to need needle valve adjustments once you get them set correctly.

Due to the design of the carburetor with it's internal pump and regulator assembly does not lend itself to being controlled by a remote needle valve.

I was just conserned about losing a finger while adjusting
with engine running

We did it for a LOT of years without remote needles. Of course you NEED to pay attention and occasionally think about what you are doing.

Lesson learned, you won't do it again. I can't stand remotes, never had any luck with them, won't use them again.

On the US 41 CC engine, shut it down to adjust it if you feel the need. Its easy to start. I have been flying mine for years, of course I called B & B and got the pitts smoke muffler and new carb. It works so much nicer!

Its likely a case could be made that remote needles actually breed carelessness. I,d bet that if stats were avaliable that the there are no fewer prop strikes with remote needles. Further I'd bet that experianced operators using forward needles may have fewer prop strikes.


John

I agree with you Ken, in fact in any crash where the needle valve didn't crack amazed me so much, I forgot about the plane I've tried all methods to repair them, even welding, but never the same as new as you mention. When the AX came out I jumped for joy seeing a separate assembly. However, as some crashed, people found that the plastic nipple broke, though less easily than the FX backplate, and a ham-fisted pilot broke a couple just refueling his plane. Sorry back to the subject.

I prefer remote needle valves myself, but sometimes I think it also can cause a lot of accidents too. I would never think about adjusting an engine from the front, especially with a carb mounted valve, but with the rear mounted needle, all too often see others starting their engines, then with the engine going full tilt, reach over the top to set the high end. Personally this makes cringe and have made suggestions whenever practicable. Just wanted to add my two cents here also.