Compensating Washer

Spring washer working together with the B-side bearing (6205-2Z) in the BG90 motor. Compensates for axial play arising from assembly tolerances and thermal expansion during motor operation.

Application

The washer presses against the 6205-2Z bearing, providing constant pressure that compensates for the motor shaft's axial play. It prevents the bearing from shifting in its seat during operation and limits vibration caused by excessive play.

Symptoms – when to replace

• Noticeable axial play in the motor shaft when the fan is moved by hand, despite a sound 6205-2Z bearing.
• Light knocking or rattling from the motor under changing load, which stops after replacing the washer.
• The washer is flattened, has lost its spring tension, or is visibly deformed when the motor is disassembled.
• Recurring, rapid bearing play despite a recent replacement of the 6205-2Z bearing alone, without replacing the washer.

How to choose the right part

Selection is based on reference number 43318 – the washer is dedicated to the 6205-2Z bearing in the BG90 motor, used both in the 115-185 models and in the Profi 160/175/195 TST series.

When replacing the 6205-2Z bearing (43.317), it's worth assessing the condition of this washer at the same time – loss of the washer's spring tension shortens the lifespan of even a new bearing.

[faq]

Does this washer need to be replaced every time the 6205-2Z bearing is replaced, or only when it's clearly damaged?|If the washer has retained its spring tension and is not deformed, it can be reused. With visible loss of tension, it's worth replacing it together with the bearing, to avoid dismantling the motor again shortly after.

The motor has axial play despite a new bearing and a new washer – what else should I check?|Check the condition of the bearing seat in the motor housing and the seating of the A-side bearing (7304 BEP) at the opposite end of the shaft – the play may come from a worn seat, not only from B-side components.

Will skipping this washer (omitting it during installation) immediately damage the new bearing?|Not immediately, but the lack of axial-play compensation accelerates bearing wear and increases motor vibration – better not to skip it when replacing the bearing, even if the old washer looks sound.

[/faq]