Me coil has sprung...

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Ross
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Re: Me coil has sprung...

Post by Ross »

Rob Frankhmr over on BM Riders Club forum posted this up to help someone there work out what where the spark had gone in their BMW.

I have done some of his testing and am just about convinced it is the coil.
Check for 12 volts at coil (Green/blue wire) (No voltage here means failure is back up the wiring via kill switch to ignition switch)
I get voltage when I do this.


At the coil, disconnect the wire that goes to the ignition module... not the Green/Blue one, Not the big thick one, the other one (black I think).

Connect a wire to this terminal and, with the ignition on, briefly short it to ground.

This should produce a spark at the plugs when the wire is disconnected from ground (it is also likely to produce a spark at the wire wher it touches ground so it's probably a good idea not to have any loose petrol in the vicinity). Provided you get the spark from this test, you can be fairly confident that it is the ignition module that's at fault... if not, then you're looking at the coil.
I get no spark when I do as above. This leads me to believe it is the coil that has failed.
Me wittle bit of the web........http://rossmz.blogspot.com/
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mattcfish
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Re: Me coil has sprung...

Post by mattcfish »

I had a Boyer ignition go out in a tunnel at rush hour. Very scary. Same issues. Could be the coil though.
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
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Ross
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Re: Me coil has sprung...

Post by Ross »

New coil is here. Still no spark. We go north in the car. :evil:

If the allen bolt head on the alternator rotor had not stuffed up I would have had an Omega system fitted well by now and would not have needed the bean can which it must be.

Will have a look when we get back in a weeks time.
Me wittle bit of the web........http://rossmz.blogspot.com/
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mattcfish
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Re: Me coil has sprung...

Post by mattcfish »

FUTURE wrote:New coil is here. Still no spark. We go north in the car. :evil:

If the allen bolt head on the alternator rotor had not stuffed up I would have had an Omega system fitted well by now and would not have needed the bean can which it must be.

Will have a look when we get back in a weeks time.
Replace that alternator bolt, you will love the crank mounted ignition. If the socket is stripped drill ahole in the bolt head and use a bolt extractor. http://homerepair.about.com/od/interior ... ractor.htm
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
kutter
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Joined: Tue Dec 07, 2010 9:50 pm
Location: Central Queensland, Australia

Re: Me coil has sprung...

Post by kutter »

Ignition Module??
3/85 R80 Mono
5/81 R100RS - Shed Find

kutter
Rockhampton
Queensland
Australia
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Hunsta
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Re: Me coil has sprung...

Post by Hunsta »

FUTURE wrote:New coil is here. Still no spark. We go north in the car. :evil:

If the allen bolt head on the alternator rotor had not stuffed up I would have had an Omega system fitted well by now and would not have needed the bean can which it must be.

Will have a look when we get back in a weeks time.
Thats bloody tough luck mate. Hope you get it sorted pronto when you get home.
Craig
I REALLY AM A NICE GUY. JUST ASK ANYONE THAT HASNT MET ME.
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Ross
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Re: Me coil has sprung...

Post by Ross »

mattcfish wrote:
FUTURE wrote:New coil is here. Still no spark. We go north in the car. :evil:

If the allen bolt head on the alternator rotor had not stuffed up I would have had an Omega system fitted well by now and would not have needed the bean can which it must be.

Will have a look when we get back in a weeks time.
Replace that alternator bolt, you will love the crank mounted ignition. If the socket is stripped drill ahole in the bolt head and use a bolt extractor. http://homerepair.about.com/od/interior ... ractor.htm
I am going to go buy some of these tomorrow. Had all day in the passenger seat of the car to think about how to fix this.
Me wittle bit of the web........http://rossmz.blogspot.com/
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Ross
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Re: Me coil has sprung...

Post by Ross »

At long last the alternator bolt is out. Screw extractor did the job. Thank you all for your advise.

Now to work out how to fit the Omega Ignition system. I should have been an apprentice to the Prince of Darkness, Mr Lucas. I am hopeless when it comes to that black magic that flows down the wires.
Me wittle bit of the web........http://rossmz.blogspot.com/
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Sibbo
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Re: Me coil has sprung...

Post by Sibbo »

You're not the only one Ross !

Did you get my K75 PM ?
"You ain't gonna learn what you don't want to know"
The Grateful Dead
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Ross
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Re: Me coil has sprung...

Post by Ross »

Sibbo wrote:You're not the only one Ross !

Did you get my K75 PM ?
I have yet to read it mate. Sorry in all the dash to go north the other day and now getting the R back on the road. Will try to read it tonight.
Me wittle bit of the web........http://rossmz.blogspot.com/
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