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)