Alan wrote:
>
> > If you need a new starter, I'd recommend a gear reduction starter, I 've
> had
> > one for over a year now.
> > TRF has them on sale for 169.00 . A fair piece of change less than I
> paid
> > back then.
> > rebuilt originals are available through most suppliers.
> > al salvatore
> > 76TR6 dailey
I'm not out to diss any of the suppliers selling gear reduction starters
for Triumphs, but I have to relate my experience with one (supplier not
mentioned--they're all coming from the same manufacturer, anyway, I
think).
The starter location on the GT6 is way down low on the right. Where I
live, rain is infrequent, but when it rains, it's sudden and torrential,
and the city here thinks storm drains are a myth perpetuated by people
who live in big cities. Lots of local and temporary flooding. The stock
starter is rather porous, and I've had lots of starter problems related
to having to run in deep water. I decided that a gear reduction starter
would be a good choice, since the mounting flange could be clocked so
that the motor would be higher than the stock unit.
Within a couple of weeks of installing the gear-reduction unit, it
started having engagement problems. Not severe, and when it wound up and
didn't engage, I could let it wind down until it was almost stopped, hit
the start again and it would engage. No big deal.
This got a bit worse over the year it was installed, but was still
manageable. Thursday before last, it left me dead in front of our local
Mexican grocery. Would spin up, but simply would not engage, no way, no
how. I finally got a push to start, and put it in the driveway. Took off
the starter Saturday before last and took it apart.
Discovered that it wasn't a bendix-related problem as I suspected. These
units have a plunger on the end of the solenoid shuttle which positively
locates the pinion gear in the flywheel before engagement. The problem
is in the gear train. The motor gear (about eight-ten teeth) engages an
intermediate gear of about eighteen teeth, which then engages the bendix
shaft driven gear, which has about forty teeth. The only connection to
the bendix drive shaft is the driven gear, through a one-way roller
clutch inside the driven gear. This clutch provides over-run protection
for the pinion, but it's also the only connection between the starter
and the bendix.
Upon disassembly, I discovered that all of the rollers were seized in
the body of the driven gear. They are made to work by inertia--they each
sit in a ramped recess in the inner part of the gear, with a return
spring pushing on each roller to return them to their original
position--and this means they have to be free to work. The driven gear
spins up, the rollers, through inertia, lag behind the rotation of the
gear and slide up their ramps, binding the shaft and the gear and, in
turn, turning the starter pinion.
Pretty simple--if the rollers slide. The problem with this starter is
that the lubricant used isn't up to the purpose, and the assembly
technique isn't the best, so there are a couple of problems which relate
to binding rollers. The first is the design: there are two more or less
square section bronze bushings on either side of the driven gear, on
which the gear rides when it is free-wheeling. Inboard of these are the
two halves of the cage containing the rollers. The land for the bushings
is slightly deeper than the thickness of the bushings themselves, and if
the bushings are driven full home (as they would be during manufacture)
they push in slightly on the cages, pinching the rollers just a bit.
And, since the grease used seems to trap wear particles, those two
conditions cause the rollers to seize, and therefore not do what they
are intended to do.
For anyone considering gear-reduction starters, therefore, I have some
advice, based on recent experience. To avoid this aggravation of lack of
engagement, I would suggest the following: upon buying a new starter,
before installation, disassemble the gear train, pull the driven gear
and back bearing off (there's not room to get even a small puller behind
the back bearing, so use the driven gear to pull off the back bearing).
Thoroughly clean out the existing lubricant from the inside of the
driven gear and repack with a good synthetic (I used Mobil 1 Synthetic
Universal Grease).
Then, with a long flat punch and hammer, very lightly move the forward
and rear bronze bushings in their lands so that the face of each is
flush with the outside of the flange retaining them, taking care not to
mess up the roller cage in the process. This gives enough clearance for
cages and rollers to work properly and to ensure that grease gets all
round the rollers, including all of their ends.
I also noticed that both of the bendix shaft bearings were unsealed, and
the one near the pinion gear seemed to be packed with lithium grease,
most of which had leaked out, as it was dry and rough, so I cleaned
those, as well, and packed them with synthetic grease, then reassembled
the gear train.
The result is a starter which works as intended, every time. I've had no
trouble with it at all since these changes.
Certainly, some of you with this same starter, operating in cooler
climes and not using your car and starter as frequently as I do (mine is
a daily driver, doing runs to work, errands, etc.) won't see this
problem immediately, but from private email in the last week, I know
that others are having this same problem, intermittently. If you've
purchased a gear reduction starter from any of a variety of sources, and
find that it spins up without engaging once in a while, this is the fix.
Otherwise, I'm quite pleased with the operation of the starter, and I
think it certainly has enough starting torque for those with
high-compression engines.
Cheers, all.
--
Michael D. Porter
Roswell, NM (yes, _that_ Roswell)
[mailto:mporter@zianet.com]
The gulf between content and substance continues to widen....
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