Rainbow D3 / D4 Motor Slinger Ring

Water filtration is the whole point of a Rainbow, and it is also the motor's biggest hazard. The slinger ring rides on the motor shaft and throws stray moisture outward, away from the bearings, every time the motor spins. Part R1979B replaces that ring on the Rexair Rainbow D3, D4 and D4SE.

These rings do not last forever. They harden, glaze, split at the seam, or begin slipping on the shaft instead of turning with it — and once the ring stops flinging water clear, the bearing behind it takes the moisture directly. The symptom arrives later as a bearing whine that grows into a growl, then a motor that runs rough and hot.

It is a teardown part: the motor will already be apart when you need it. Seat the new ring square on the shaft so it runs true, and inspect the bearing itself while you have access to it.