Rotarians,
Does anyone have a good second gen single stage
turbo they want to sell?
Failing that - can someone recommend a good
supplier / rebuilder?
Yes, you guessed it - I flew for almost an hour
this morning, then fried the turbo. I'd noticed a bit of slack in the bearings, so
was expecting to have to rebuild it anyway - just not quite this
soon.
The good news is that the failure mode was fairly
benign. I was trying out the turbo at 5000ft and just passing through 170
kts making large circles over the field. The rpm dropped from about
the 4500 I was using to 3500 and no amount of throttle would increase it
from there. Below 3500 the engine ran almost normally, so I had enough
power to climb if needed. It was maybe a tad rough, but not so's
you'd notice. An observer says I put out a puff of white smoke, and was
trailing a small amout of white smoke as I headed back in for a normal
landing. In all I ran the engine for about 10 minutes after the turbo
shaft broke. I lost about 1 pint of oil and the same of coolant through
the collapsed bearings, so perhaps another 10 minutes or more would have
been ok if the field had been further. The exhaust wheel was
floating around in the wastegate housing, but too large to get through the
hole, so all it did was block the exhaust a
bit.
I guess this is the "experimental" part of the
exercise. :)
John Slade
Rotary Cozy IV (currently sans
turbo)