Bug lost power while driving. wont start

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rrb6699
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Bug lost power while driving. wont start

Post by rrb6699 »

I :arrow: was driving about 50mph nicely and it died. I left it in gear to see if it would come back but no spark. its night here. I was not far from home. got a buddy to tow me back. I tried starting fluid, but, as I suspected no spark. could the coil just die like that? I checked the battery and fuses, panel, etc. and didnt see anything burnt or disconnected.

it seemed like something came disconnected the way it just lost power. just sudden loss and I knew it wasnt gonna start. I just got it running good and smoothly yesterday. it was smooth thru all the gears. I just kept leaning out the carb.
Anyway, the starting fluid told me no spark. im thinking coil fail, but, what else should I check?
RR

1972 Restoration Project.
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Piledriver
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Re: Bug lost power while driving. wont start

Post by Piledriver »

If you have a voltmeter or test light, check for 12v at the coil first.If you forgot to tighten the distributor, re-engage it and reset your timing.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

it was a broken spade plug (it still was/looked plugged in) from positive on coil to rotor. I dont know what broke it. maybe got brittle from years of heating/cooling. surprised me a bit when it fell apart.
RR

1972 Restoration Project.
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Marc
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Re: Bug lost power while driving. wont start

Post by Marc »

Do you have an electronic ignition pickup (Pertronix for example)? They have no condenser and two wires going from the distributor to the coil, typically red & black...if reversed the pickup will be destroyed. The comments below apply to the stock points-style ignition.

If your condenser wire is connected to the (+) terminal of the coil, the polarity's reversed. It still works that way but the spark intensity is lessened.
Term 15 (+) should have the black wire bringing power from the ignition switch, another feeding the choke heater and cutoff jet on the carb, and a third going to an inline fuseholder which supplies the backup light switch on the transmission.
Term 1 (-) should have the wire going to the condenser/points. Normally it's green, but some aftermarket condensers use black.

in mid`71 when the dealer diagnostic plug was added on the firewall, many small wires were added - none of which is vital to operation. Those cars'll also have a gray/green-stripe wire on Term 1 and perhaps a white one on Term 15.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

I have Pertronix most likely since it is close to what you describe. I took off the diagnostic plug when I replaced the wire harness. I wasn't sure what it was. I thought this car may have had an automatic shift stick originally. it looks like the engine was replaced due to the engine number starting with a 126 number indicating it was a generator motor at one time.

all wires are hooked up to the coil as you describe except I never hooked up the electronic choke because the carb works fine without it except on cool or cold mornings, but, there are very few of those in FL and it only takes up to 10minutes max to "settle down" if its below 45 degrees
RR

1972 Restoration Project.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

I still have a starting issue. I have been trying to track this down. some background: I purchased the standard bug replacement starter last year in December. I didnt know it at the time, but, there should have been a bushing included with it. the symptoms matched up to the tech bulletin (and bushing) I saw on one at AutoZone when I asked the clerk there to pull one so I could look at it before I pulled it. I told them my starter had neither the bushing or tech bulletin.

as it turns out one guy there owned a few bugs and said to replace this starter (on my '72 Beetle 1600 DP Standard Transmission) with a 1973 Squareback Auto Transmission starter and it would solve the bushing problem. once I saw this starter it made sense since the starter did not have the long shaft past the starter gear therefore did not require a bushing.

I put this starter in and went to try it and just a click. nothing. I tried a few more times. nothing but a click. went to bed started the next day (Labor Day) by going out, removing the tire (still on jack stands) and switch the S wire to the other spade plug. nothing but a click again. then I looked at the battery connections, wiggled those, re-tightened them. Went to the fuse block and wiggled those wires and re connected everything there one at a time. wiggled the ignition switch plug and wires there.

went to try and start it. bam. started right up. throughout the day I started it 4x to drive the Bug around and help charge the battery in case it was drained from the start attempts.

finished some fiberglass work and decided to go get some Chinese food. click. no start. I was gonna roll start it but let the clutch out to stop the car (barely started rolling). turned the key and it started. picked up the food (parked it in a place to roll start it just in case). came out. turned the key. click. nothing. I had to roll start it.

now it wont start at all. I replaced the ignition switch with a new in box backup thinking I burnt the contacts on that one but it still wont start. just click.

at least I know it will start but, am running out of things to try here. it started normally 4 times but nothing now.

ideas?
RR

1972 Restoration Project.
Ol'fogasaurus
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Re: Bug lost power while driving. wont start

Post by Ol'fogasaurus »

Normally if you had a stock ignition I would have suggested the condenser but since it did started back up I would suggest the grousting straps. There is a woven ground strap that goes from the battery to the chassis then to the trans. Try running a temp, not braided, ground strap from the beg battery post to an engine/trans bolt just to see if that could be at least one of the potential problems.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

you mean a jumper cable? I know I cleaned that connection last year when I first changed the starter but didnt look at it this time.
RR

1972 Restoration Project.
Ol'fogasaurus
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Re: Bug lost power while driving. wont start

Post by Ol'fogasaurus »

Yep, the so called jumper cable. Those braided ground straps have a long standing habit of those little woven strands breaking down over time. Older American cars used them in the past and they were a pain in the posterior even back then.

Not saying that is the problem but it should be a cheap test to eliminate one possibility. Check the hot lead and connection also. Also the ground should be the same gauge as the hot lead.

Even today bad grounds are still a problem.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

would it have zero resistance still or show resistance if it deteriorated? I'm sure I can find braided ground straps still. the one on the battery looks like new still. I may have replaced it. cant remember but it doesnt look 45 years old. I will still clean that connection and I keep the battery posts clean monthly. ill try that test on the transmission and replace it as a matter of totally eliminating it as a near future possibility.

I have 00 gauge copper braided I can replace the battery positive cable with. it seems to be close to the same gauge, but ill have to put an end on the starter side. that leaves the S lead. I believe its the one attached to the fusible link under the rear seat correct? I can check it from there to the starter, but, goint back to the fuse block may have to be toned out to find it.

I didnt replace the main wiring harness the previous owner did that, they replaced the starter switch & keylock too. that is wired from the fuseblock to the starter switch. or at least some wires are. that could have a problem too.

still a lot to check. hopefully I will get lucky and find it on the next step with the grounds or hot cable.
RR

1972 Restoration Project.
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Piledriver
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Re: Bug lost power while driving. wont start

Post by Piledriver »

We have gone from a no start to a no or intermittent crank issue, and eliminated the starter most likely.

I call ignition switch, or resistance in the starting circuit due to 30 feet of old wire etc.
A relay back by the starter can do wonders and is a very, very common fix, some places probably still set the "hard start kits" that include a $5 Ford starter solenoid. (a good 30-40A std cube relay also works, but has to be kept dry)

RE: Ground strap:
Your DVM doesn't pass any significant current checking resistance. The ground strap will see 150+ amps.

I had a 76 Rabbit (Mk1 Golf everywhere else) with a annoying slow battery discharge issue, alternator worked great, (new) battery would not charge properly.(disconnecting it when parked did not help matters, no slow discharge)
Ground strap looked fine and passed the tug test and ohmed zero...
Momentarily shorted the battery to ground jumping it one day (hit front bumper with jumper cables) and later found a speedo that went to >90MPH with any fwd motion...
It blew the little spring in my speedometer..??? :shock:
The ground strap ohmed fine but couldn't pass any current.
The dead short to the body passed enough current through the spring in the speedo to pop it like a fuse, via the speedo cable. There was some resistance in the braid.
Braid traps water and contaminants.
Braid rots from the inside...
Braid sucks.

Replaced the woven ground strap with a short hunk of battery cable, and replaced my speedometer.
Charging problem (and a whole host of other random electrical weirdness) all went away.

I run TWO 000(0?) ground welding cables off the trans, both sealed swaged jobs, one to the body and one to the battery.
I still look at them whenever I'm under the car.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

ok,
thanks for your time and help here.

first, remember the main harness and fuse block are both new as of a few years ago. both replaced by the previous owner.

also, this thread covers 2 different issues.

1) I started it with the overheating no start issue where given that the starter works, but, if I drive say 20 miles and stop somewhere, if I restart it too soon, then in about 1/2 mile the car begins to lose power/bog and die. then I have to wait 30min before it will start again. I've been told this is vapor lock. still have this issue.

2) this no start began awhile ago as an occasional occurrence, but, lately started happening very frequently and finally I replaced the starter (still under warranty) with a starter thats new that was recommended for the bushing issue. its the starter for a 1973 vw squareback with auto trans). had it not started 4x yesterday, I may have taken this starter back. anyway, now I'm at a "no start always" with this issue.

given that the harness and fuse block are new, the tranny ground strap IS 45 years old. forgive my ignorance, but why run 2 wires for ground to transmission and negative on battery? certainly the length of cables will not be very long. second, if I do run these should I make them identical lengths? my 00 cable comes from pieces I used to wire a breakerbox in a boxtruck I'm customizing that I put a 15,000w generator on. I have green, black, white and red colors. ill run green and black from the tranny once you tell me why I should run both of these.

will that gauge be ok for the positive battery cable as well to the starter - let me know.

here's the list in order of things i'm gonna do:
..
- replace ground straps from tranny nose to body and and negative on battery. should I leave the braided on the battery to the body or replace that? or can I eliminate that one since I'm running the ground from the starter to the negative on the battery?

- replace the positive from battery to starter positive.

-replace the fusible link under the rear seat on th S cable? with a wire tie

-check the ignition switch plug if the previous things don't solve the issue.

I'll wait for your reply first.
RR

1972 Restoration Project.
Ol'fogasaurus
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Re: Bug lost power while driving. wont start

Post by Ol'fogasaurus »

Getting basic:

The woven flat wire is made up of many pieces of thin wire that is braided/woven into a light and flexible flat strap used for grounding. The woven style of strap is a very old way of doing things! The braided strap has clamps at each end to hold the braid together; e.g., keep it from unraveling. The holes in the end clamps are for connecting to the battery at one end and, if I remember correctly, the hole in the right side of the shock mount on the torsion tube at the other end. There is a more conventional grounding wire that goes from it to the transaxle (or do I have it backwards... been too long since I have had to deal with the flat strap since I play with buggies).

As the flat strap, like any other wire it corrodes with age, can also work harden and start to break down so it can't do its job as it once did (not talking down to you here). Usually the work hardened/ages wires will start to break apart (fray) usually at the clamps but that is not always the place where it happens. Electricity, like stress likes to travel down the path of least resistance which is the outside of the wire. If it were a tube it would also travel down the inside surface. Corrosion can interrupt this easy flow path in several ways.

Without getting much deeper into electronics, the ground wire is usually the same gauge/capacity as the positive wire which, in turn, can also age and deteriorate but it is covered with a sleeve so you can't see it as well. Again, the positive wire usually will start to fail at the clamped ends. At 45 years one would have thought that one or both of the wires had already been replaced at least once or more.

Lee
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Piledriver
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Re: Bug lost power while driving. wont start

Post by Piledriver »

given that the harness and fuse block are new, the tranny ground strap IS 45 years old. forgive my ignorance, but why run 2 wires for ground to transmission and negative on battery?
you have to have a direct ground to the trans>engine as thats where the alternator is.
You have to have another connection to the body as everything else grounds through the body.
The factory does it that way too.

That battery to body ground is usually right behind the battery.
I like to put it off the trans on the same (longer) stud as the battery to trans connection to avoid battery-area related corrosion, and the fact that on many ACVWs the metal in the battery area is not in the greatest shape.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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rrb6699
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Re: Bug lost power while driving. wont start

Post by rrb6699 »

ok I did the grounds as you suggested. I just tried it and got a good start 4x so far. the real test will be a real errand. as with the leaks, they did not start till the minute I decided to glue in the carpet. hmmphh.

thanks for all your help so far) on this. I should have recognized the symptoms. occasional no start. then more and more frequent no starts. makes sense something wasnt conducting electricity as well and over time it was getting worse.

ill keep you posted.


so, my last issue is the engine dying after a 20+ mile drive when I stop for less than 30 minutes it wont start.
RR

1972 Restoration Project.
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