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Remote Needle Valve, or Standard?

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Remote Needle Valve, or Standard?

Old 02-25-2003, 04:38 PM
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Small Fry
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Default Remote Needle Valve, or Standard?

I just bought a Magnum .46 to go on my LT-40, and was wondering what I should do with the needle valve. I like the remote idea because it keeps my hands away from the prop, but what do you guys think?
Old 02-25-2003, 04:58 PM
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Steve Collins
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Default Remote Needle Valve, or Standard?

I have heard of a lot of problems with the remote needles, primarily with air leaks. I prefer the standard ones. They are enough challenge without the added problem of airleaks.
Old 02-25-2003, 05:02 PM
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MinnFlyer
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Default Remote Needle Valve, or Standard?

I've never had an engine with a remote NV. But I really have to question how much safer they really are. After all, It seems like most people don't get hit with a prop while ADJUSTING their NV, it comes more from putting their hand through the prop arc while REACHING for the NV, or the glow igniter, or whatever else. Let's face it, if you're working safely from the back of the plane, and you approach the NV carefully from the rear, it's not going to make much difference whether your fingers are 1" or 2" away from the prop.
Old 02-25-2003, 05:11 PM
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Small Fry
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Default Remote Needle Valve, or Standard?

MinnFlyer, that's why I questioned it. It seemed to me that if it was so good, then why isnt it the standard? I'll just keep it the way it is now.

Thanks!
Old 02-25-2003, 05:22 PM
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tiggerinmk
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Default OS LA's

I have 3 OS LA engines, all with remote needle valves.
I've had no problems with air leaks on any of them.
With a standard valve, the carb is very close to the back of the prop, so if you are behind the engine adjusting the needle, its still easy to stick your finger into the back of the prop.
Moving the valve to the back just gives you an extra inch or so of comfort so you are less likely to graze your fingers or knuckles on the back of the prop.

Of course if you're in the habit of sticking your hand through the prop arc from the front of the engine, then you're beyond help anyway.....
Old 02-25-2003, 08:43 PM
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cwat212
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Default Remote Needle Valve, or Standard?

I have a few engines with remote needle valves and have never had a problem with air leaks. I have noticed no difference in performance from the remote needle valve. They seem to work the same as the normal needle valve.

I like the extra space for safety reasons.
Old 02-25-2003, 10:46 PM
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big max 1935
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Default Remote Needle Valve, or Standard?

Years back we used to be able to get a needle valve extension about 4 inches long with a spring in it & a knob on the end. May be time has come for it again?>>>>>>>>big max 1935>>>>>>
Old 02-25-2003, 11:17 PM
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CafeenMan
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Default Remote Needle Valve, or Standard?

Small Fry - Remote needle valves are safer and I have had no problems with them either.

But there are two things about remote needle valves that I don't like. I'm assuming the type of remote valve that is mounted on the engine backplate.

First, it requires that the engine be mounted further forward to pass fuel lines. Some of my planes had standard valve engines on them and when I switched to a remote valve engine I had to buy a new engine mount and rebalance the plane - sometimes with lead in the tail.

Second, I've noticed that the there is a lag between adjusting the needle and the engine responding. I have no idea why that should happen since the flow should change immediately and the engine should respond immediately. It's not a big deal, but I had to break my habit of just turning the needle until the engine was on song. Now I have to turn it a little and wait a couple seconds for the engine to catch up. Nobody I've talked to has experienced this, but I've noticed it on three engines (2 are the same make though).

Overall, I think it's just a personal choice. As I said, my remote needle engines run fine, so take your pick.
Old 02-26-2003, 06:02 AM
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kobago
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Default Remote Needle Valve, or Standard?

It is wonderful that a needle can be adjusted delicately with making an airplane fly. The position of a needle seems to change in the ground and the sky.
But, because that change is adjusted in advance, I don't feel the need of a remote needle.
It is that someone must add one servo that I hate it.
Therefore, it is never good to become increase in 2 ounce thing weight for a airplane.
kobayan
Old 02-26-2003, 02:31 PM
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G.F. Reid
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Default Remote Needle Valve, or Standard?

Kobayan, I think that you have misunderstood what is meant by "remote" in this case. What we mean by remote needle valve is that it is not attached directly to the carburator but instead, it may be mounted to the firewall at the rear of the engine compartment in order to keep one's hands away from the propeller. What you're calling a remote needle valve, most people here would call 'in flight mixing'.

Does anyone recall a simple remote needle valve manufactured by Atlantic RC? I have one that's been operating trouble free for nearly 7 years. Really not even a valve. You pass the fuel line through it and it literally "pinches" the line as you adjust the fine machine threaded extension rod clockwise and releases it as you turn counter clockwise. Non intrusive and no leaks.
Quite ingenious in it's simplicity. Wish I'd bought 5 of them.
Old 02-26-2003, 02:48 PM
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TerrellFlyer
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Default Remote Needle Valve, or Standard?

I prefer the standard location on the carb.,I've had some air leaks with the remote needles.
Old 02-26-2003, 05:53 PM
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Bruiser-RCU
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Default RNV

I've never heard of anyone having a leak where I fly.

The remote needle valve is safer, no doubt.

Some allow you to position the needle in such a way that is exits the cowl on the left, right, top or bottom of the airplane.

Some are hollow and have a set screw so that you can insert a piece of wire to extend them.

There is some lag when you adjust the needle valve. You turn the needle and have to wait a moment for the change.

Why don't all engines have them? I believe most O.S. engines have them. I may get bashed here, but if you buy a O.S. clones to save a little money keep in mind the manufacturer has to cut costs somwhere so you can save a few bucks...

JMHO,
-Bob George
Old 02-26-2003, 06:10 PM
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TerrellFlyer
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Default Remote Needle Valve, or Standard?

Hi Bruiser, the worst air leak I've ever had was on a OS91FX
Old 02-26-2003, 06:49 PM
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SMALLFLY-
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Default Remote Needle Valve, or Standard?

second that, I dont know of anyone who has owned a OS 91 fx with remote valve that hasnt leaked. I really like the new TT design, not remote but it angles away from the prop a bit. Anyway I would not take what kind of needle valve it has in to any consideration, weight, power, and longevity are much more important
Old 02-26-2003, 09:08 PM
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CafeenMan
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Default Re: RNV

Originally posted by Bruiser
I may get bashed here, but if you buy a O.S. clones to save a little money keep in mind the manufacturer has to cut costs somwhere so you can save a few bucks...
Not by me you won't. I don't buy clones because I think they're evil. They're vultures who let someone else front the costs of R & D (costs much more than manufacturing) and then basically steal the design for nothing. I don't care how well they run or if "it's the best engine I've ever owned!" I won't buy a clone if I'm sure that's what it is. It's getting harder to tell these days because engine manufacturers are like everyone else - monkey see, monkey do. So all engines end up looking like the leader's engines even if they were R & D'd by the company that manufacturers them.
Old 02-26-2003, 11:17 PM
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Default alcohol probably boils....

Hi everyone.
A previous comment is sorry. it was my misunderstanding.

I have an OS91FX motor, too. I want to explain one of my experiences. As for a cause of kind of this air leak, a needle is hot by the heat from a motor that alcohol probably boils. It will be probably repaired if cooling of the motor is improved. . . . much wind is blown to a motor, fuel is made rich. We want to warn that a needle is squeezed too much even in winter against us.
But, if pressure is being given to a fuel tank, it won't be able to enter air from the needle part.
kobayan
Old 02-27-2003, 12:03 AM
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FLYBOY
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Default Remote Needle Valve, or Standard?

OS is now making the remote standard. It costs a ton for a new carb with the needle where it should be. The remote needle sux worse than anything they have done yet as far as I am concerned. I really dislike it. I have 3 engines with it and it poses a bunch of new problems. It works so far, but I much prefer it where it was on the carb where it belongs. I figure if a guy can't keep his hands out of the prop turning it where it was, he should get help. Moving it an inch or two back doesn't save him anything. Its just more linkages to have a problem with.
Old 02-27-2003, 02:07 AM
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pinball-RCU
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Default Remote Needle Valve, or Standard?

I think the remote needle on the O.S. .46 FX (the only one I have experience with) is a terrible design. My problem with the engine is not how it runs (it runs great) but that the needle bracket breaks off if you look at it sideways (or dig a hole in the grass with the prop). Also, there is the problem of routing the fuel line, which is a pain as well. I get tired of buying new brackets. Give me a Thunder Tiger any day.

Ann Marie Cross says O.S. will never go back. However, she was not able to give me any data or science that proves the remote valve is safer. I don't think you can hurt yourself that badly touching the inside back of a prop idling, but maybe I'm wrong (I'm not a scientist enough to try it). On the other hand, if folks are not getting behind the engine after starting it, then they are just as likely to put a finger in the prop path getting to the glow plug heater as the needle valve.

I don't know the Magnum. If the needle valve is mounted in a way that keeps it out of the way in a crash, or if it's easily repaired, I think I would prefer the tiny extra bit of safety of the remote. I don't see why a remote needle would leak air any more than a carb-mounted one. It's just that with the remote you can see the air in the fuel line. With the carb-mount, the air would still enter the carb and affect the fuel mixture. An "O" ring is an "O" ring.
Old 02-27-2003, 05:16 AM
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Ed_Moorman
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Default Remote needle valves

I don't know what it is with the OS .91FX that makes its remote needle leak air or whatever causes it to lean out. There are 4 in my club and 3 have had the problem. The 4th is on an Ultra Stick 60 and never gets to full throttle so this may be the reason he has never had the leaning problem.

The OS LA's with the plastic needles don't leak, neither have I heard of the .46 or the .61 having problems, only the .91.

My personal opinion is to use the KISS principle. Adding a banjo is another place for a leak, whether it is Thunder Tiger or OS. I'll take mine up front.
Old 02-27-2003, 12:48 PM
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TerrellFlyer
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Default Remote Needle Valve, or Standard?

Hi Ed_Moorman,in the last year I've seen two OS 61's leak air at the needle valve,one took a larger O ring to cure,the other took a different brand of needle valve assembly.
Old 03-18-2003, 02:27 AM
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loopnspin
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Default Remote Needle Valve, or Standard?

I have 3 2-stroke O.S engines with remote needle valves. I have not had any trouble with any of them. One thing that I am surprised that I haven't seen mentioned here in reply to this posting is the use of tie wraps. These are generally used to keep wiring together. I use small ones to secure fuel lines to the brass tubes that come out of the fuel tank, then to both ends of the fuel filters, then finally to both sides of the needle valve and then to the carburator. This really ensures no air leaks.

Jeff
Old 03-18-2003, 05:23 AM
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MAJSteve
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Default Remote Needle Valve, or Standard?

My experience is with K&B remotes - 3 out of 4 leaked air. The fix was a piece of thin cardboard as a washer and not tightening it too hard. No air leaks after any of the fixes, so I consider it a one-time thing to do.
Old 06-19-2005, 02:07 AM
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milomorai
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Default RE: Remote Needle Valve, or Standard?

I have the O.S. LA .40 with remote needle valve. Still need to break it in and put it in the Sig Kadet Sr. I'm building. Should I get a longer mount or can I move the valve to the fire wall somewhere so it sticks out? I'm planning on enclosing the whole thing as much as possible and have access hatches and a remote glow.

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