Hooking up Battery wrong.

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canada karl
Posts: 699
Joined: Tue Jan 06, 2009 3:50 pm

Hooking up Battery wrong.

Post by canada karl » Thu Jun 27, 2019 2:18 pm

Seems like I'm getting careless in my old age. Further to post about forgeting the coolant on start up. I just remembered that I also had the Po and Neg hooked up wrong for a few seconds when I installed the battery. Would that fry the points and condensor? That sure would explain the rough running. Where is the best place to buy points and condensor for an E12 these days?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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528i-1981
Posts: 268
Joined: Wed Feb 07, 2018 5:50 am
Location: Boston North Shore, MA

Re: Hooking up Battery wrong.

Post by 528i-1981 » Thu Jun 27, 2019 8:16 pm

Did you turn the key with the battery poles reversed? Without doing so, the ignition circuit remains open so polarity wouldn't matter. Even if closed, I don't think a reversed polarity would permanently damage the coil, points or condenser. I believe that only electronics with diodes are likely to be damaged. The L-Jet ECU has diodes, but I believe it has protection against reversed polarity.
(oo=00=oo) Eric
1981 528i Manual

canada karl
Posts: 699
Joined: Tue Jan 06, 2009 3:50 pm

Re: Hooking up Battery wrong.

Post by canada karl » Thu Jun 27, 2019 8:43 pm

Here's an update. I pulled the distributor cap and lo and behold the the cap contacts are black with carbon and the rotor dosn't look too good either. Going to install new cap rotor,points,condensor. I'll pull the plugs too. My problem is I have 5 older cars and must have missed the BMW at tune up time.
I'll post an update. Thanks to those who responded.
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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Mike W.
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Location: Sonoma County

Re: Hooking up Battery wrong.

Post by Mike W. » Fri Jun 28, 2019 9:58 am

canada karl wrote:
Thu Jun 27, 2019 8:43 pm
My problem is I have 5 older cars and must have missed the BMW at tune up time.
I don't have a collection like that anymore, but it's why Iog everything in a spreadsheet for the car. I still forget, but at least I've got a record of when things were done.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

canada karl
Posts: 699
Joined: Tue Jan 06, 2009 3:50 pm

Re: Hooking up Battery wrong.

Post by canada karl » Sat Jun 29, 2019 7:48 am

Good idea Mike. I'm going to keep a record of maintenance. Do you just have the one E12 now?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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Mike W.
Posts: 2447
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: Hooking up Battery wrong.

Post by Mike W. » Sun Jun 30, 2019 11:37 pm

canada karl wrote:
Sat Jun 29, 2019 7:48 am
Good idea Mike. I'm going to keep a record of maintenance. Do you just have the one E12 now?
Yes I do, I sold the '80 a couple of months ago. Nice kid bought it, I need to do a post on the sale.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

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