Hi all,

I'm servicing and refurbishing a large floral clock (the one in
Auckland's Albert Park for those who might know it). Part of
the reason for doing so is that recently it's been stop-starting

I've got the motor and gearbox at home now

http://home.clear.net.nz/pages/joecolquitt/mvm.html

It's a Metropolitan Vickers BC 2408. Fairly typical appliance-
type single-phase motor, 230V 1/4hp 1425rpm, with reduction
gearing and end-plate to drive the minute hand, which isn't that
minute BTW

http://en.wikipedia.org/wiki/Metropolitan-Vickers

I suspect that the problem is overheating. The motor runs but
after perhaps 20 seconds from cold it turns off. When it restarts
some seconds later the time until the next stop becomes
progressively shorter. The motor does seem to be hotter than
you'd expect after only a short run time. I think I detect a little
knocking, which could be a bearing. It does run 24/7 after all,
and has done for many years. Everything is at least 40 years
old so I'm told

I can identify the start cap, but the other two devices are not
familiar to me. The black box (actually a deteriorating plastic
cover on a yellow box) above the start cap and a two-terminal
something behind the 'Warning' cover on the end of the motor

When the motor stops there are two clicks. I presume the first
is the protection relay dropping out, the second would be the
motor's internal centrifugal switch. I can't tell where exactly the
first click comes from though

So, questions -

Would the wires on the bottom of the yellow box (picture 4) be
some sort of thermocouple ?

Even if a bearing is worn, would you think that could cause so
much heating in a few seconds to trip the protection ? There's a
service tag for the gearbox dated Nov 03 (possibly just an oil
change), but the motor appears untouched. As you can see, the
wiring is getting a bit scruffy and could do with replacing. One
obvious option would be to get a new motor. An ordinary one
such as this can be had quite cheaply, but I'm still keen to learn
what could be wrong with the present one

TIA

Joe

As an aside, much of my youth was mis-spent on the abandoned
pier next to Fort Gilkicker in the south of England. It had several
ancient Metropolitan Vickers electric cranes. I took a large brass
name plates off a motor, had it polished and lacquered and made
into one fine-looking, if ridiculous in hindsight, belt buckle

http://en.wikipedia.org/wiki/Stokes_Bay
http://en.wikipedia.org/wiki/Fort_Gilkicker

I did hear that the pier was used by Queen Victoria's train as part
of her visits to Osborne House on the IOW. Doubt my crane was
there to lift her luggage though
--=20
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