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I have an RV-6A 0-360 c/s prop 650 hours Channel chrome cylinders burns 1 quart in 6 hours. SDS EM5F fuel and ignition systems run LOP. Dynon Hdx panel. I've owned it for 4 years flown 200 hours in that time.
Always thought about balancing the prop. Have normal vibrations,
Compressions just checked cold 80/75,76,79,79 borescoped exhaust valves look very good. cylinder walls no real scratches. Oil changes every 25-30 hours Blackstone labs are clean as is filter. Phillips X/C 20/50
Here's the kicker. I decided to put on an Active Balancer ring from Balance Masters to see if it would work. I like the concept.
We Dyna-Vibed the engine before install 0.41 At 71 degrees. After install 0.31 at 61 degrees. Not real good HUH?
Flew aircraft on autopilot: 4500 feet 2300 RPM WOT (26.0 Inches) First hour and half smoother than before. Liking it!!!
Then out of the blue, the engine/prop started going WA WA WA no up and down of RPM just a vibrating/pulsing like the prop was going to come off. Checked all parameters of engine all good.
Pulled throttle back to 20" and 2200 RPM and it smoothed out enough for me to not land and check it out. Anything over 2220 and the vibration came back.
Headed home at that rate. Still at 4500 feet and 100 miles from home. When descending through 4100 feet 20" 2200 RPM I could make the vibration come back 21.5" through 15.0"
Getting close to home I started to play with it:: The higher the RPM (2400) the greater the vibration. Wa Wa Wa
AS long as I keep the RPM below 2300 in cruise and 20" it's fine. Oh ya when taking off RPM is 2740 WOT no problem.
I checked the valve travel and all are in spec, Ranging from .392-.410
Oh ya I even got a second Balance Master ring and it was no different. Worse yet, is I now have a vibration/pulsing noise without the Balance ring. Something is going BAD and I think it just popped it's ugly head up. And the RPM is steady.
But what????? I could say a ton more, But, this is the jest of it. Something is happening and it ain't good for sure.
Any ideas would be helpful.
My luck usually varies FIXIT
Always thought about balancing the prop. Have normal vibrations,
Compressions just checked cold 80/75,76,79,79 borescoped exhaust valves look very good. cylinder walls no real scratches. Oil changes every 25-30 hours Blackstone labs are clean as is filter. Phillips X/C 20/50
Here's the kicker. I decided to put on an Active Balancer ring from Balance Masters to see if it would work. I like the concept.
We Dyna-Vibed the engine before install 0.41 At 71 degrees. After install 0.31 at 61 degrees. Not real good HUH?
Flew aircraft on autopilot: 4500 feet 2300 RPM WOT (26.0 Inches) First hour and half smoother than before. Liking it!!!
Then out of the blue, the engine/prop started going WA WA WA no up and down of RPM just a vibrating/pulsing like the prop was going to come off. Checked all parameters of engine all good.
Pulled throttle back to 20" and 2200 RPM and it smoothed out enough for me to not land and check it out. Anything over 2220 and the vibration came back.
Headed home at that rate. Still at 4500 feet and 100 miles from home. When descending through 4100 feet 20" 2200 RPM I could make the vibration come back 21.5" through 15.0"
Getting close to home I started to play with it:: The higher the RPM (2400) the greater the vibration. Wa Wa Wa
AS long as I keep the RPM below 2300 in cruise and 20" it's fine. Oh ya when taking off RPM is 2740 WOT no problem.
I checked the valve travel and all are in spec, Ranging from .392-.410
Oh ya I even got a second Balance Master ring and it was no different. Worse yet, is I now have a vibration/pulsing noise without the Balance ring. Something is going BAD and I think it just popped it's ugly head up. And the RPM is steady.
But what????? I could say a ton more, But, this is the jest of it. Something is happening and it ain't good for sure.
Any ideas would be helpful.
My luck usually varies FIXIT