Bizarre Battery Connection

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PaducahFrank
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Bizarre Battery Connection

Post by PaducahFrank » Wed May 16, 2018 1:15 pm

Sometimes I drive the 1978 2.0L FI Bus (non California) on a short trip. It is parked for an hour or so. I come back and turn the key to the run position, the radio and idiot lights come on. Then I gently (everything I do with the Bus is done gently with a high degree of finesse) twist the key to the start position. Sometimes this results in the lights going out, the radio going dead, the starter not turning. Going back to the run position, even after going all the way over to the off position, does not correct this and the lights and radio remain dead. I go back and gently jiggle the ground cable going to the battery and twist the battery terminal a little. Sometimes it moves sometimes not - but mostly no movement. if the key is in the on position this will result in the idiot lights coming on and the radio coming back to life. Then usually a gentle twist of the key results in a clean start.

This baffles me. I have cleaned and put that battery terminal grease on the negative and positive terminals, removed and reinstalled the terminal on the ground strap, which is not original equipment, and tightened the bejesus out of both batter terminal connection clamps. What could be happening here?

It's like the resistance between the negative terminal on the battery and the ground strap is infinite until you mess with it a little.
Paducah Frank

1978 2.0 F.I. Non Cali Westfalia
1974 Triumph TR6
2005 Chevy Colorado

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sped372
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Re: Bizarre Battery Connection

Post by sped372 » Wed May 16, 2018 1:26 pm

Sounds weird. At first thought I'd suspect the ignition switch, but you mention that you sometimes find the battery terminal connection loose? Really? They should be tight - you shouldn't be able to move them by hand. I like to rotate/twist them as I press down to seat the clamp and then snug the nut. Try to give it a twist after and it should be solid.
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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Randy in Maine
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Re: Bizarre Battery Connection

Post by Randy in Maine » Thu May 17, 2018 4:34 am

The first thing I would do would be to go to the local battery shop and have them make you a new + battery cable to the starter. I had them use 2 gauge "welding wire" (very flexible) and 2" longer, new terminals (heat shrink please). It cost me $22. I had them use red cables by convention even though black was stock from the factory.
79 VW Bus

PaducahFrank
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Re: Bizarre Battery Connection

Post by PaducahFrank » Thu May 17, 2018 9:23 am

I replaced the ground wire between the battery and chassis a while back because the original braided wire would get hotter than hell while the starter was engaged. I got a real long wire, the kind that the battery connector clamps onto the wire. I wonder if this might be my problem. If, by some crazy mechanism, the resistance between the connector and the wire goes to infinity when conditions are just right. I wonder if I soldered that wire to the connector would fix it. It is an intermittent problem.
Paducah Frank

1978 2.0 F.I. Non Cali Westfalia
1974 Triumph TR6
2005 Chevy Colorado

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Randy in Maine
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Re: Bizarre Battery Connection

Post by Randy in Maine » Thu May 17, 2018 11:51 am

I would just replace all of them with quality ones.

Do the + cable maker thing like I did up above and take the battery ground cable AND the chassis ground at the front of the transaxle into them and they will set you up well for cheap money well spent.
79 VW Bus

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Amskeptic
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Re: Bizarre Battery Connection

Post by Amskeptic » Fri May 18, 2018 9:30 pm

PaducahFrank wrote:
Thu May 17, 2018 9:23 am
I replaced the ground wire between the battery and chassis a while back because the original braided wire would get hotter than hell while the starter was engaged. I got a real long wire, the kind that the battery connector clamps onto the wire. I wonder if this might be my problem. If, by some crazy mechanism, the resistance between the connector and the wire goes to infinity when conditions are just right. I wonder if I soldered that wire to the connector would fix it. It is an intermittent problem.
If the connection is not actually secure, a high amperage event, like a starter call, can cause an instant oxidation between the post and the terminal. Youy have to scrape the oxidation off. Remember, "tightening the begeezus" out of a battery terminal clamp that is damaged is just wasting your time, The two ends of the clamp drawn together by the bolt/nut *must not touch each other. Once they do, you have to either replace it or re-configure it. I tighten my battery clamps *lightly*. The lead is soft. The ends of my 14 battery terminal clamps in seven cars do not touch, I get good clamping readily.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

Rob in NH
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Re: Bizarre Battery Connection

Post by Rob in NH » Mon Sep 03, 2018 6:35 pm

Resistance is Futile.. a Battery cables may look great from the outside, But cut them open and you may find it's all green inside from corrosion..

Electrons flow on the surface of wire, corrosion slows down the electrons and resistance begins.. once you have too much resistance things start to die.. Sure it might say 14 volts at the Battery positive and at the Starter connection, But hit the key and the resistance weakens everything.. I have twice gotten Cars for FREE that needed nothing but a Battery cable..

Leads get hot because they are fighting the resistance and generating heat (or a Starter with high resistance).. enough heat to melt the post clean off the Battery!, I would replace both leads and the frame ground strap.. and just like a Car Stereos Amplifier.. IF you added a 2k or 4k Farad Capacitor in parallel with the Battery there will be no drain noticeable on other items like Lights..

I would also add Volvo Relay to activate the Starter closer to the connection where there can be less resistance. Basically a Solenoid or 50Amp Relay activating the Solenoid on the Starter.. I have had great luck with the 50Amp Relays with the large spade connectors found in most Volvos..

The Capacitor upgrade your going to LOVE!, Most of these alternators and generators only work/charge at a certain RPM, But with the Capacitor storage keeping the battery and voltage smooth and at the same level all the time (it charges and discharges in milliseconds) it makes everything electrical not fight for the 70% of the Batterys power during a start and even lower idles are possible.. Same thing of course as what it was made for.. taking the electrical HIT from an Amplifier..

I'm not new to this I'm 50 years old and I'm on my 16th air cooled Volkswagen.. You can take everything I say with a grain of salt.. But I can guarantee you will enjoy the mentioned updates... especially if you have not heard of them before.

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