Subject: Re: Starter problem still....
Author: Patrick Hayes
Date: Apr 7, 2005, 8:43 AM
Post ID: 1718664396
Greg Bender wrote:
a longer throw (or, more precisely, a more foward pushing throw). But,
| if the starter gear is getting pushed all the way out every time, then I think you are stuck with having a gear wear problem. |
Lannis: I think I'm with Greg on this. And continuing your symptom
will only make matters worse.
Look at how the system operates. It must be a clear, two-step process.
When you hit the button, the relay and then the solenoid get
energized. The solenoid pulls its core inward, which pushes the starter
gear forward through a pivot lever. The starter motor is not yet
energized and does not yet spin.
As the pinion gear moves forward, the forward edge of its teeth are
supposed to impact against the rear edge of the ring gear teeth. Both
sets of teeth should be angled or tapered in some way to discourage a
direct, face-to-face tooth hit. At the point of impact, the pinion
should be forced to rock one way or the other to slide between mating
ring gear teeth.
As the teeth fully mesh and engage, the huge contacts down at the back
end of the solenoid inside its cap come into play. When these contacts
hit, the starter windings themselves become energized and the motor
starts to spin.
So, you have one of two problems.
First, is there some reason that the gear teeth do not embed? Has this
error caused the teeth to grind against each other, square off, and
exacerbate face-to-face locking? Can you get at the damaged teeth with
a dremel grinder and restore a pointed face condition?
Second, is the starter being energized to spin before the gears are
meshed? This is my suspicion. And here again we have two potential
problems. Somehow the starter is getting juice before the gears are meshed.
First, has there been enough wear to the pivot and the various
mechanical points of the lever system so that it is not pushing the
pinion gear as far forward as it used to? Not sure how to repair that,
but you could remove the lever and have a little weld dab added to it to
restore original thrust dimension.
Second, has someone repaired, cleaned or replaced this solenoid? Was an
alternate substitute solenoid used? If it is the original solenoid, and
it was cleaned or repaired, was the original cap gasket saved or
reproduced? The physical position of the solenoid rear cap (and thus
its internal contacts) are critical to the design of this system. If
you move the cap slightly forward (by omitting the cap gasket) you allow
the starter contacts to come into play before the plunger thrust is
complete. If you use an alternate solenoid, the dimensions for thrust
and contact may not be completely accurate.
I would suggest a thorough tooth inspection and some lubrication of the
pinion shaft to get the gear sliding easier. You can run the solenoid
repeatedly on the floor with some test wire and observe its action.
Just be sure to disconnect the heavy starter lead so you don't energize
that spin or the motor with jump all over the place.
I would suggest a removal and very thorough inspection of the pivot
system and the fork face of the pivot against the pinion gear. Is there
some substantial wear and can it be improved or corrected?
I would suggest disassembly of the solenoid and the addition of a double
or triple thick gasket between the end cap and the solenoid body. By
adding gasket thickness here, you are moving the motor contacts aft and
delaying the instant point of energizing the starter. The plunger has
to go deeper before it makes the motor spin. Perhaps by stacking
gaskets, you can delay it long enough to get deeper tooth penetration
before spin. At any rate, what you have now is a rotary grinder and you
are damaging the face of the pinion and ring teeth. By doing so, you
are making the gear contact position worse as it respects the internal
solenoid contact position. You have to get tooth penetration BEFORE
spin. Doing the gasket stack might be enough to counteract the tooth
wear already in place.
One last thought. You might ignore ALL of the above and just inspect
the wiring at the starter and solenoid. You maybe haven't done
something to short this wiring in some way, or hooked it up incorrectly
so that the thrust action and the spin action are happening
simultaneously? That would be a case for failure for sure. You have to
separate these two functions in time and space. The starter relay ONLY
energizes the solenoid. It is the action of the solenoid which
energizes the starter windings. I'm trying to imagine how you could
hook up contacts incorrectly to get the motor spinning by the relay
circuit rather than by the solenoid circuit. Could happen I suppose.
Patrick Hayes
Fremont CA