Ignition trouble re-surfaces (long)

The ignition trouble I was having with my new SVDA dizzie has re-surfaced. To be fair, it is only presumed that the trouble is with
this distributor, it could only be coincidence.
Re-capping from last week:
1. Driving along, then noticing that the tach was getting spasmodic, spiking up and down. Then engine dies. First time this happened, I checked to see if the voltage on the line from coil to points was switching when I hand turned crank -- no, voltage remained at zero. Install 009, get jump (drained battery trying to start the darn thing), drive home, examine distributor, no problem found, re-install SVDA, things are fine again.
2. Next day it happens again ALMOST same symptoms, (tach, engine dies, will not start again), but this time I did find that voltage on coil-dizzie wire was switching, indicating that points were operating, and did find spark at plug wire #4 at least. But car would not start. Remove SDVA, install 009, car starts, limp home.
3. Replace points and condenser in SVDA, re-install, car drives fine for one week. Problem solved.
/Or so I thought./
(Ominous music)
4. Today, pulling into driveway, engine just quits. Starter does not even turn engine over. Grumble grumble. Make a couple phone calls, eat a sandwich, turn key, car starts easily. Looks at me innocently. "What problem?"
WTF?
5. Drive to train station to hop commuter train to meet wife in nearby town to watch "Touching the Void" at beach town theater. On way to train station, notice one upward spike of tach. "Uh oh," I think. Then notice that tach is reading high. I know what the engine sounds like and the tach is reading high. Reads 1200rpm when engine is idling (idles at 950 and sounded like it), reads 5200 when engine is at 3800 when I normally shift. I shift by ear and know there is no possible way the engine was running at 5200.
6. Back to car. Now it's dark (all other fault times were in daylight). Tach starts out okay, but GEN lamp starts glimmering. Then gets brighter as headlights get dimmer. Tach reads higher. Managed to get home without getting hit or hitting anything, but battery is clearly faded.
Will look into all this tomorrow. Either alternator is not charging, or something is pulling a lot of current. Tach is apparently showing high when voltage is low. But what causes spikes in reading while driving? Momentary drops of voltage? With ignition off, tach has needle resting at about 1000 rpm. What causes engine to suddenly die? And changing dizzie to (apparently but maybe coincidentally) fix this? Why did car die this afternoon in driveway with not enough juice in battery to start it, yet 15 minutes later, car started just fine?
These and other mysteries are, I think, all tied to a common fault. But while I slumber away the night with the sleep of the innocent, perhaps some more intelligent form of life -- someone who knows how these things work, for example, or someone in a different time zone, or some poor tortured soul with insomnia -- will look at this list of symptoms and say, "ah ha!" And explain It All.
Then again, I might just have to hack at this until I find it myself. I'm man enough.
-- Mike "Rocket J Squirrel" Elliott 71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer) KG6RCR
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On Fri, 16 Apr 2004 21:37:48 -0700, "Mike Rocket J. Squirrel Elliott"
...,.hmmm. Interesting cunundrum. I'd take a good hard look at the ground connection from battery to body, and from boddy to transmixer first. Once those are confirmed clean and tight, move on and make sure the positive connection is clean and tight on starter. If all those check out fine....might wanna take a close gander at the ignition seitch as a potential culprit.
...Gareth
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Thank you Gary -- some good ideas, and worth looking at. Others folks itching to weigh in on this discussion are urged to read my top post first as we are not just discussing a GEN lamp issue, but a slew of symptoms.
Gary Tateosian wrote:

Replaced with new grounding strap after second Incident. At same time I replaced the battery's +12 lead to/from starter/alternator. But nevertheless, this is goodly advice and I'll be poking a prodding all the connections a bit later this morning.

Uh -- what's a transmixer?

If the connection to the start was bad, say it fell off, that would not light the GEN lamp. It gets its + voltage feed from the alternator. If the ground connection from the battery to the chassis was bad, then that lamp could not even light in the first place.

A failed ignition switch /could/ cause the sudden engine stop. It /could/ cause the starter to refuse to kick over, and it /could/be responsible for it being willing to start again 15 minutes later. The wiring from the switch to the starter has been upgraded with a starter relay.
But I don't know if a failed ignition switch could cause those tach spikes, its high reading, nor could it cause the headlights to start dimming on the way home last night and the gen light to start to brighten at the same time. I may be dealing with more than one problem.

--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
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I'm now thinking something is shorting out intermittently. Tranmixer is transmission. Biggy ground strap at front left. I would check every place a wire might have been disturbed / moved / re-routed / touched / considered / looked at while doing the engine removal and replacemet. As soon as you're ready, you can help me with my tranny problem! - BH
Mike Rocket J. Squirrel Elliott
in message wrote:

look at the

At same time I

starter/alternator. But

prodding all

make sure

that would not

alternator. If

bad, then that

ignition
stop. It

/could/be
later. The

with a starter

those tach

headlights to start

start to

one problem.

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Now wouldn't that fall into the little electronic niche that MY simple mind can never seem to comprehend - the way "they" try to 'splain it to me, is, "THIS path has MORE + (or) LESS - than that path..." Or does that apply here? -BH
<<<SNIPAROONIE>>>
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Busahaulic wrote:

Does what apply here. I'm thoroughly lost.
--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
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When you have a multiple of electrical problems, you most likely have a circuit finding a completion to ground back to the battery by some path other than the one it was designed for many times routing through other electrical items giving you erratic systems from them and masking the real problem. Look at the big picture and reground or add more grounds so the electricity finds an easier path back to its' home base (the battery). Be patient and good luck....Dennis
href="http://community.webtv.net/weewiktype1/Dens1978Puma ">Den's 1978 Puma</a>
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Hi guys -- I think I sorted out the problem several days ago. I believe the problem was a crap connection between the alternator and the battery.
--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
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Mike Rocket J. Squirrel Elliott wrote:

Add a ground wire from the alternator body to the chassis if you don't have one already. There's a screw hole for that purpose on top of the alternator, back where the strap is.
Jan
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-------------------------------------------------
Not just anywhere on the chassis. It should go to the same grounding-point used by the battery -- ideally, to the negative post of the battery itself.
The voltage comparitor used in the regulator chip uses the frame of the alternator as its ground reference, which may vary by as much as a volt from the battery.
----------------------------------------
As early bugs aged, a significant number of dead battery and failure-to-charge complaints were traced to high resistance in the ground-path between the regulator (mounted under the rear seat) and the battery (also under the seat but on the opposite side). The fault was most often in a bad terminal but sometimes at the battery ground, sometimes at the regulator, usually do to corrosion on the former and rust at the latter. The easy solution was to run a grounding braid or wire between the two.
Steel simply isn't that good a conductor. Adding a grounding buss of extra-flexible 8 gauge cable from the front of a bus to the battery is often all it takes to clear up years of electrical complaints.
-Bob Hoover
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Thanks Bob
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Thanks guys -- this makes sense. I did see the threaded hole in the top of the alternator, a great location for a ground wire.
However, I seem to have reasonably good low-resistance connection between alternator frame and battery negative: 13mV when the engine is at 2,000 rpm.
--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
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It may be too thin to carry enough AMPS?
Jan
Mike Rocket J. Squirrel Elliott wrote:

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On Fri, 16 Apr 2004 21:37:48 -0700 "Mike Rocket J. Squirrel Elliott"

Do you have a dwell meter? This would be a good time to use it. It might show up some problem in the distributor that is intermittent.

When I get intermittent voltage problems I hook up a voltmeter and leave it on the floor where I can glance at it when things start to go wrong. It beats trying to guess.
BTW, your 71 would have a generator, not an alternator, unless you've changed it.
- ----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA -----------------------------------------------
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Jim Adney wrote:

Mr. Dwell-o-meter sez dwell is hokey-dokey. So the next thing is to "remote" it -- use the same line that feeds Mr. Tach-o-meter and observe from the pilot room when the gremlins are up to their mischief in the back.
[snip]

New (or so the invoice that came with the Wonderbus claims) engine w/alternator.
--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
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"Mike Rocket J. Squirrel Elliott"

Mike Have you tried disconnecting the tach completely, all wires, just in case you are sending 12v or grounding the coil at the wrong times ?
James
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