It sounds as though you have been bit by the same bug that got me when I did
bearings on my spa pump. It sounds as though you have the rotor to "deep"
on the bearings. Hard to explain but the "back" (non-pully) end of the
shaft is to close to the end of the cover. This causes the entire rotor
assy to sit further back in the case causing rubbing noises. You will have
to addjust the position of at least one (if not both) of the bearings to
"move" the rotor further forward with respect to the case.
It could just as easily be to far forward also. look for the rub marks and
this will give an idea of which way to push/pull the brarings to make the
rotor position correct.
I'd invest in a bearing puller (at AutoZone or similar) to pull the bearings
off with, it's very easy to bend the shaft or break the case with a hammer
(and yes I've done both)
Bearing are really fairly neat things you can contact almost any bearing
supply house (King Bearing on the west coast) and give them the number off
of your bearing and get a replacement. King even had main bearings for my
Honda Motorcycle. I would be a bit skeptical about new bearings that turn
"smooth as silk" I hope you mean they are smooth, but stiff. If I remember
right these are sealed ball bearings and should have grease in them, which
will make them stiff.
steve hanselman
tr6@kc4sw.com
-----Original Message-----
From: owner-6pack@autox.team.net [mailto:owner-6pack@autox.team.net]On
Behalf Of Cregg Cowan
Sent: Tuesday, May 14, 2002 2:48 PM
To: triumphs@autox.team.net; 6pack@autox.team.net
Cc: cowan@erg.sri.com
Subject: TR6 altenator (Lucas 15-ACR) reassembly (longish)
Hi Triumph enthusiasts,
I'm having trouble re-assembling the alternator from my (sort of) daily
driver 71 TR6. It is one of the old 5-wire types.
The alternator was working but making a whirring noise, which I assumed to
be the front bearing. I was encouraged by the article at
http://www.vtr.org/maintain/alternator-repair.html and found an inexpensive
source for the bearings (NTN 6202ZZ) at
http://www.arrowweb.com/bake/home.htm
Unfortunately, both bearings were making noise but I had ordered two just
in case. I replaced them both, re-soldered the slip ring and was feeling
pretty good until I assembled the front (pully end), windings (stator?) and
rear (rectifier end) and noticed something was rubbing inside the case.
After much examination the problem may be that the case goes together too
far (hard to explain). That is, if I don't tighten the 3 machine screws
(which hold the front and back together), leaving them loose by ~1/8 inch,
then the rotor turns smooth as silk (as you'd expect with new
bearings). Unfortunately, everything (front, windings and rear) is still
loose without the screws tightened. When I tighten the screws, a plastic
"spacer" between the rotor and the rear bearing (which protects the wires
to the slip ring) rubs against the inside of the rear casing.
OTOH, I had difficulty in removing the rear bearing and tried to remove it
by prying on the bearing while tapping the rotor shaft with a hammer. The
rotor was supported by the jaws of a bench vise at the time and so the
rotor *could* have moved on the shaft, but I see no signs of
it. Furthermore, I tried to reverse the process ;-) by hitting the other
end of the shaft with no noticeable effect.
Now, finally, the question(s):
1. What is supposed to keep the plastic spacer from rubbing the case?
2. Should the rear bearing be the same as the front one? The one I
removed was indeed an NTN 6202ZZ, but who knows what happened on some
previous rebuild.
3. Is there a locating mark on the rotor shaft? How can I verify the
rotor is in the correct location.
I know I could more replace the Lucas unit with a reliable Delco or Bosch,
but I am loath to admit defeat at this point.
Regards and TIA,
Cregg Cowan
71 TR6
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