5-28-05 .5
hours / 48.2 total
I used my new ACES 2015
balancer today to balance the prop.
Ended up adding 19.3 ounces of weight at one spot. I used 1900 rpm on the prop, which
works out to be about 5300 on the engine. This seemed to be about the worst
spot, with 6000 being just a bit lower in vibration. The instructions say to use a low
cruise, and this is probably as low a cruise as I’ll ever be at.
AT 1900 prop rpm, the initial
vibration reading was .45 ips, and the solution was to add 18.5 gms to one
spot. I used the split weight
function to add two smaller amounts of weight to the existing spinner screw
holes. This was great, and gave a
reading of .06 ips. I then used
the balancer to calculate the diff in weight for the permanent spot inside the
flange of the spinner, and it came up with 19.14 gms. I ended up using 19.3 gms, since the
longer screw would be more inboard, and have less effect, and also because I’d
be drilling a hole, and removing a little weight. This was perfecto, and the final run
was also at .06 ips.
While I had the analyzer out, I
did a vibration spectrum survey at the front hub, and at the front housing on
the engine. At the front hub, the
only peak was the prop itself. On
the front housing, there were no prominent peaks up to 10,000 hz. To me, this means there isn’t any
other significant vibration such as rotor imbalance, flywheel, counterweights,
etc.
Took the plane for a quick spin
around the area, and it’s like night and day. No more compass spinning like it’s
possessed from the vibration at full throttle. Just dandy, and much better for my
evap cores and such. I still hate the fuel transfer pump
though.
I can also officially report
that my oil leak is gone, gone, GONE!
Temps are awesome, but still could close the oil scoop some. I climbed from 80 ft to 5000 feet at
100 mph, with a ground OAT of 88 degrees. Max oil temp was 186, and coolant was
215. The cowl baffle keeps them
in the 160’s for oil, and 180’s for
water in cruise. Running
out of excuses not to fly someplace.