Repairing a microwave

[Scott]

My microwave oven is probably 20+ years old (Panasonic). The
turntable judders, stopping and starting. I wonder how easy this
would be to repair. Is it like a turntable on a record deck? Is
there a drive belt that stretches over time? Can you simply remove it
and fit a new one? How would I measure the correct size?

[Brian Gaff]

Most are gear driven from a motor. You may well find many models use the
same little motor/gear unit, but the fixing holes can be different. Often
the hardest bit is getting at it, and cleaning out all the crap to see if
its just crap or whether the little nylon gears have their teeth worn or
stripped off. As to whether its worth it of course is a whole other matter.
Brian
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Post by Scott
My microwave oven is probably 20+ years old (Panasonic). The
turntable judders, stopping and starting. I wonder how easy this
would be to repair. Is it like a turntable on a record deck? Is
there a drive belt that stretches over time? Can you simply remove it
and fit a new one? How would I measure the correct size?

[Scott]

Post by Brian Gaff
Most are gear driven from a motor. You may well find many models use the
same little motor/gear unit, but the fixing holes can be different. Often
the hardest bit is getting at it, and cleaning out all the crap to see if
its just crap or whether the little nylon gears have their teeth worn or
stripped off. As to whether its worth it of course is a whole other matter.

Thanks. Can I safely open it up to investigate (unplugged from the
wall of course) or will it be difficult to reassemble?

[Andy Burns]

Post by Scott
Can I safely open it up to investigate (unplugged from the
wall of course) or will it be difficult to reassemble?

start by looking underneath, you probably won't have to go anywhere near the
dangerous bits, just a couple of lucas spade connectors for 240V to the motor.

[alan_m]

Post by Andy Burns

Post by Scott
Can I safely open it up to investigate (unplugged from the
wall of course) or will it be difficult to reassemble?

start by looking underneath, you probably won't have to go anywhere near
the dangerous bits, just a couple of lucas spade connectors for 240V to
the motor.

Often the underside of the oven has a cover just for the motor and the
motor can be removed from the bottom.

Motors are almost universal and spares are under £10.

[David Wade]

Post by Scott
My microwave oven is probably 20+ years old (Panasonic). The
turntable judders, stopping and starting. I wonder how easy this
would be to repair. Is it like a turntable on a record deck? Is
there a drive belt that stretches over time? Can you simply remove it
and fit a new one? How would I measure the correct size?

The motors often have a plastic gear that changes the direction of
rotation, which goes brittle. However new motors seem expensive

https://www.espares.co.uk/product/es132365/microwave-turntable-motor

might have one for your model. If you leave it on with and it has a
clock replacement might be money saving. Old microwaves often had high
standby current

Dave

[Andy Burns]

The motors often have a plastic gear that changes the direction of rotation,
which goes brittle. However new motors seem expensive
https://www.espares.co.uk/product/es132365/microwave-turntable-motor

About half that price from eBay, I fitted one a couple of years ago, look under
the microwave, it probably has "weak spots" ready for you to hack a hole in the
bottom using tin snips/pliers, and then screw another motor in place.

There's not too many model numbers to match-up the old one

[Andrew]

Post by Andy Burns

Post by David Wade
The motors often have a plastic gear that changes the direction of
rotation, which goes brittle. However new motors seem expensive
https://www.espares.co.uk/product/es132365/microwave-turntable-motor

About half that price from eBay, I fitted one a couple of years ago,
look under the microwave, it probably has "weak spots" ready for you to
hack a hole in the bottom using tin snips/pliers, and then screw another
motor in place.
There's not too many model numbers to match-up the old one

Juddery turntables on Panny microwaves seems to be a common
complaint if you look at the reviews on Currys or JL's
website.

Simply cleaning the three wheels on the turntable ring
might improve matters.

[Paul]

Post by Scott
My microwave oven is probably 20+ years old (Panasonic). The
turntable judders, stopping and starting. I wonder how easy this
would be to repair. Is it like a turntable on a record deck? Is
there a drive belt that stretches over time? Can you simply remove it
and fit a new one? How would I measure the correct size?

https://newscrewdriver.com/2022/10/07/microwave-turntable-repair/

The motor is a clock-works item. It has gears inside, to
reduce the mains-frequency rotor rotation, to turntable speed.

The encapsulated motor usually has a geared end sticking out, but
that does not drive the turntable directly. The turntable is
glass, and they use a plastic piece for intermediary propulsion.
This part "slips" under various conditions, such as if the
turntable is not sitting squarely on the plastic piece.

Sometimes, it is the plastic piece which is worn out. The motor
still rotates at a constant speed, but the plastic adapter
is slipping, and not spinning the turntable.

This means, if you're buying parts online, you would buy
both a motor and the plastic adapter, unless you knew
for certain, which was at fault. Some people don't like
to open the bottom cover on the microwave, unless they know
they have the parts to finish the job.

The turntable bearing is a ring of plastic with three wheels.
I had to fix one of those once (rather than buy a new one,
the microwave was rather old). I fashioned a fairly thin
end cap for one of the wheels, and that lasted for many more
miles. But it wasn't really all that strong. The turntable ring
fits into a runner area in the bottom of the microwaving volume,
and goes round when the turntable rotates. When parts of it
jam or a "tyre is flat", it will make noises and run out of
its gentle groove. It's not often that you can fix one
of those (rather than buying new).

Paul

[Animal]

My microwave oven is probably 20+ years old (Panasonic). The
turntable judders, stopping and starting. I wonder how easy this
would be to repair. Is it like a turntable on a record deck? Is
there a drive belt that stretches over time? Can you simply remove it
and fit a new one? How would I measure the correct size?

They use a small all in 1 geared motor with a plastic knob on top. The turntable rides on this knob and a 3 wheeled plastic ring. Juddering is caused by any of:
tt not correctly positioned on wheels
muck or rust where the wheels run
less often, muck in the wheel 'bearings'
The motors are universal, can normally use one from any dead nuke. And are replaced from the underside.

[Davey]

On Tue, 3 Jan 2023 16:21:39 -0800 (PST)

Post by Animal
The motors are universal, can normally use one from any dead nuke.

Instant image of Chernobyl! Transport might be expensive, though.

[Brian]

Post by Scott
My microwave oven is probably 20+ years old (Panasonic). The
turntable judders, stopping and starting. I wonder how easy this
would be to repair. Is it like a turntable on a record deck? Is
there a drive belt that stretches over time? Can you simply remove it
and fit a new one? How would I measure the correct size?

Worth looking.

Our first uWave - bought in about 1980 - lasted many years. The turntable
was driven by a thick rubber belt. When it snapped, I replaced it with a
large O ring which looked identical and cost 35p.