When a washing machine becomes unbalanced, it may start to vibrate excessively. The vibrations can quickly cause collateral damage, so it's a problem that needs immediate attention. You can often fix the problem by redistributing the load -- often a single heavy item in a light load can unbalance the drum. If that doesn't help, you may or may not be able to diagnose and fix the problem without taking anything apart.
Check the Level and the Subfloor
It's important for the washing machine to be perfectly level -- if it's tilted, the load will shift in the direction of the slope and unbalance the drum. To check the level, put a spirit level on top of the machine housing and arrange it in both the left-to-right and front-to-back directions. Turn the feet in the front of the machine with a wrench to adjust the level -- this is easier to do if you lift the front of the machine with a crowbar.
If the subfloor under the machine isn't stable, any vibrations will become more severe, quickly unbalancing the load. If strengthening the subfloor isn't an option, put a piece of 3/4- or 1-inch plywood under the machine -- the larger the sheet of plywood, the better.
To address most other problems that could cause the drum to unbalance, you'll have to remove the front, top or back panel of the machine. Consult your owner's manual to find the correct procedure for doing this.
Look for Shipping Bolts
Just before you disassemble the washing machine to look inside, check your manual for the location of the shipping bolts, especially if the machine is new. If the bolts haven't been removed as they should have been, they could be causing the vibrations. Remove them with a wrench.
Check for Damaged Components
Having ruled out shipping bolts as the cause of the problems, it's time to turn your attention to the components of the unit designed to support the washer tub and dampen vibrations:
- Shock absorbers: If your unit is a front-loader, it probably has one or more shock absorbers connected between the outer tub and base frame. Make sure they are all connected at both ends and that none of them are leaking fluid. If one is leaking, it's best to replace all the shock absorbers, not just the damaged one.
- Suspension springs: Both top and front loaders have a series of springs holding the tub to the base or suspending it from the top. Make sure all these springs are connected and that none is distended. If you have to replace one, replace all of them.
- Snubber ring: Made of plastic or felt, the snubber ring provides a cushion for the tub of a top-loading unit, and when it wears out, the tub can contact the metal base. Dust on a plastic snubber or clumps on a felt one are signs of wear. You must remove the suspension springs to remove and replace the snubber.
- Dampening straps: Some top-loaders have four rubber straps holding the tub to the four corners of the machine. If one of these fails, the tub goes out of balance. If you have to replace one, replace all of them.
- Driver bearings: Some front-loading machines have ball bearings between the tub spindle and the motor shaft, and if the casing wears and one or more of the bearings become dislodged, the tub will vibrate. This is a major repair that requires considerable disassembly of the unit. If the bearings are worn, you might consider replacing the washing machine.
Chris Deziel is a contractor, builder and general fix-it pro who has been active in the construction trades for 40 years. He has degrees in science and humanities and years of teaching experience. An avid craftsman and musician, Deziel began writing on home improvement topics in 2010. He worked as an expert consultant with eHow Now and Pro Referral -- a Home Depot site. A DIYer by nature, Deziel regularly shares tips and tricks for a better home and garden at Hunker.com.