[PeteSS2018]

509Driver ... I had a similar issue (perhaps not the same) with clunking coming from the drive snout on my 2.9 Whipple. As it turned out, I took it to a shop who disassembled the front and found that the coupler (a plastic part that connects the input shaft to the rotor pack via these steel prongs) had completely disintegrated. Basically, the coupler had broken/cracked and gradually was ground up into plastic powder like it had been put in a blender. The input shaft prongs were basically directly contacting/driving the rotor pack prongs and still turning the blower, but the noise was very different to the "ordinary" Whipple sound.

The workshop said they'd never seen anything like it. But got a new coupler - cheap and easy to get - which Whipple said was a newer type of material. Never had a problem since.

The blower was only about 10,000 km (6,000 miles) old when that happened.

My suggestion, if there is a LOT of play in the input, is take the snout off and check the coupler is in tact.