Bosch Washing Machine

This thread was marked as solved. Here's a summary of the problem and the fix, generated from the discussion below.

Bosch washing machine rattles/knocks on spin only with heavy wet loads

The problem

The Bosch washing machine makes a loud rattling or knocking noise during spin, but only when the drum is somewhat full with heavy items that hold water. It is quiet on wash and on an empty spin cycle. The machine is level. The dampers were replaced with no improvement. The internal weights were checked and reported as OK, with nothing obviously broken.

Likely cause

The strongest diagnosis in the discussion is that the weight of wet laundry is making a slightly loose or cracked component move enough to create the noise. Suggested suspects were slightly loose bolts, slightly loose concrete weights, or a cracked casing/chassis, wheels or feet. The exact fault was not confirmed.

What fixed it

No confirmed repair was documented. Recommended action was to inspect with the appliance isolated from the mains, removing the lid and vigorously moving/bouncing the tub and checking for anything loose, broken or cracked, then carefully eliminating possible noise sources. Further diagnosis should be carried out by a suitably qualified appliance engineer.

Checks to try

• Machine level checked
• Dampers replaced
• Internal weights checked and reported OK
• Empty spin cycle tested with no noise
• Wash cycle reported fine
• Suggested inspection with lid off after disconnecting from mains
• Suggested vigorous shaking/bouncing of tub to identify loose parts
• Suggested checking bolts, concrete weights, casing/chassis, wheels and feet for looseness or cracks

Parts or tools mentioned

• Dampers