Rusty Fan Pulleys #28 60

Dave Baker is just now in the process of helping out with a 503 that ate its fan belt last weekend. Rusty pulleys. The engine seized quickly once the belt had gone. I read a report of a pilot killed when his Rans stalled on take off caused by the belt breaking and subsequent seizure.
It also happened to Dave Baker a couple of years ago. Now I haven't heard of the problem with 447, though I can't understand why, as the fan/pulley set up is the same as a 503.
Skydrive supply cadmium plated pulleys, at a reasonable price for the 503's. If your pulleys are rusty I suggest you get a new set.
They are available for 447's.

The big pulley fits the engine shaft: (with one shim on the cord) the smaller disc is one half of the fan pulley, with the Rotax tool/spanner for holding it when unscrewing the fixing nut.

A new plated fan drive pulley
Two new halves came & replaced my old rusty ones, including removing engine gearbox & propeller in one piece to access the fan belt for inspection, replacement & shimming tight. All very straightforward using carpet on a couple of milk crates to sit it on after first removing the under ali cover and the plugs (clean rag into their holes pro temp) so it could sit flat safely on the cylinder heads. Since I fitted them I've seen no rust on mine & the belt tension has stayed excellent for years.