Post by Phil Allison"Gareth Magennis"
"Phil Allison" "Gareth Magennis"
Post by Gareth MagennisDenny, I found that if you oil the bearing and the bearing is f**ked,
what happens is that the rotor shaft will, for a while, spin inside the
seized inner bearing, until it sticks to it again a day later once the
oil runs out.
** The fan / transformer used in MacroTechs has a plain bearing.
A steel shaft running in a bronze bushing.
If it is not horribly worn, a drop of oil fixes it.
Didn't fix mine.
** So fucking what ?
It has fixed every one I have ever seen.
Denny, buy the spares, it's guaranteed to work first time, and its 2
bolts to remove and replace.
** You sure we are speaking about the same amp?
Macro Tech 2400 ?
http://imgs.inkfrog.com/pix/karolina/DSC07306-Crown-Open.jpg
http://i50.tinypic.com/2ppj3hv.jpg
That white blade fan looks thoroughly buried to me and there are numerous
wires to attach.
There is no ball bearing in that fan.
If you think replacing it is a job for some half-witted " sound ingineur
" - you must be stark raving nuts.
.... Phil
Hi Phil,
well you are right and I am wrong, there are no ball bearings in the fan.
Here's 2 photos:
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You can see the bearing is free to rotate in the end cap, but is fitted too
tight to turn freely, though it can be turned with a screwdriver. The shaft
turns inside the bearing which remains stationary.
The other end cap I believe has an identical bearing, but I don't have that
any more.
What happened to this one was I freed off the other bearing/shaft, which was
the problem, but embarrasingly the customer brought it back a couple of days
later as it had seized again. The other end of the shaft was again tight in
the bearing making nasty noises, and the bearing was "crunchy" when you
tried to move it with a scewdriver, so I assumed that was the problem, i.e.
it was supposed to turn freely.
Like you I have freed these in the past, and not had problems, I don't know
why this one did not remain freed off.
The spare parts available are, I believe, the rotor and bearing in the
photos, and the other bearing in its housing. These can be removed and
refitted to the rest of the fan unit without having to dismantle any wiring
IIRC.
Denny, if you are going to attempt this, the white fan blade is a very
tight press fit onto the shaft and can be cracked if you are too heavy
handed. Mark the blade before you remove it, otherwise it is possible to
fit it back on the wrong way round, and your amp will suck instead of blow,
and may well overheat.
Cheers,
Gareth.