My
water pump pulley departed the flange in-flight last night
… fortunately I was right overhead on cross wind … heard a
fwaap and a buzz thought something went through the
exhaust
or had lost an accessory belt;
scanned the gauges, water temp and pressure were building
fast, I cut the throttle and headed for 06 … checked
the voltmeter which showed +14V so was pretty sure at
least one belt was driving the alternator … made
my best landing in a long time then taxied back to the
hangar. Probably should have shutdown the engine right
away but didn’t and it boiled over in front of the
hangar. Of course my brother was there to see this bird
fly for the first time; not exactly the demonstration I
wanted. Popped the top cowling and found the water pump
pulley departed but still inside the cowling.
The outer belt was turned completely inside-out, which is
probably what made the buzz.
There
are only four small bolts holding that thing in place …
noticed in Haynes pictures this morning that some have
four studs and four bolts … guess the studs are for adding
a second pulley?
– but they would also add extra drive surface area. I
think I put those bolts on with standard loctite but am
not 100% certain. Anyway now I’m wondering if my
restrictor plate, loading the pump, may have contributed
to more vibration or is this just coincidence …
Jeff