multicasting

I'm looking for help with a norvel .61 engine. I finished my HOB P-47, and was testing the engine on the airframe. I noticed that it was very finicky when attempting to get it to idle down.

When i began looking for air leaks, I noticed that the whole needle assembly was wobbling, as it it were loose. After removing the needle, I tried to tighten up the nut, and realized that there is no rotating barrel on the norvel, the throttle only moves the needle valve.

Te problem is that now that I have removed the nut holding it all together, upon reassembly, the needle spring (clip holding the needle in place) is not connected to the control horn. I do not know how they had the two connected.

Once that problem is solved, I still have to deal with the engine running poorly at idle.

Any help?

rrragmanliam

My Feedback: (1)

Multi, on the nNorvel .061 the needle valve spring simply sits on top of the throttel lever, followed by the nut. So if yopu were looking at the front of the motor from left to right you have 1.fuel jet (the thing you hook your fuel line to) 2. venturi, 3.throttle barrel, 4.throttle lever, 5.needle valve spring,6.needle valve nut, 7. needlevalve. I put the two arms of the needle valve spring in line with the throttle lever but it really doesent matter how the needle valve spring is alligned in relation to the throttle lever. Hope this helps.

Darren

Sory for the crappy pictures

multicasting

Did you locktite the nut to keep it from coming back off?

rrragmanliam

My Feedback: (1)

No, and I wouldn't recomend Locktighting anything you want to take apart in the future. Theres just too much torque required to get the parts apart without damage. Also the needle assembly on my norvels wobbles a bit also. I make my needle adjusments then wait 4-5 seconds for everything to settle down befor making further adjustments. The wobble doesn't seem to effect the motor when your not touching the needle. As far as the eratic running goes, once you know everything is together correctly I'd look at the following.

A. Is the engine completly broken in. After it's run for about 30-60 min. total things will smooth out a bunch.

B. What kind of fuel are you using? 20-25% nitro, and 20% oil seems to be the minimum to make these engines purr especially at idle.

C. How many head shims are you using, two is the right number on my Norvels, many people use three.

D. Is you engine an AME or big mig. The AME engines are tighter and generaly require moer break in.

Darren

2fast4u

My Feedback: (5)

Yep...High Nitro, 20% oil, BALANCE THE PROP, and I use a bit of fuel tube to "seal" the needle valve assy. I never have had any problems.

Good luck and let us know how it all turns out.

gcb

Darren,
Have you tried blue Loktite? It is supposed to be good for situations where you need to remove something in the future. I use it but have not yet had to take anything apart I have used it on.

George

rrragmanliam

My Feedback: (1)

Hello George, No I havent tried it. I used locktight on a prop nut years ago then had a hell of a time getting the nut off when I broke a prop. I endded up having to use a pair of needlenose vice grips on the drive washer and a socket wrench on the nut to break it free. I completly distroyed the drive washer. Now I'm a little gun shy with the lock tight. If you try it and have no problems let us know, it would be a good security measure.

Darren