'78 darmah - suddenly electrics completely dead

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doug s.
Cucciolo - the Lil Pup
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'78 darmah - suddenly electrics completely dead

Post by doug s. » Sat Sep 03, 2016 7:42 am

hi all!

ok, so i parked my '78 darmah last week, after riding it ~60 miles round-trip to work. everything was fine - started right up, ran great, etc. yesterday, i went to take it to work again, and when i turned the key - nothing. completely dead. the battery is old, but usually kept on a charger; last week, i was lazy and did not connect it. (i don't have the connector wire hooked up, so i have to pull the side cover off.) so, i got on another bike and rode to work; and checked out the darmah further when i got home yesterday afternoon. hooking up the battery charger showed it was at 95% charged. the four fuses in the little fuse box underneath the front tank/steering stem area all have continuity. (tho i did blow the one on the left, by touching something adjacent w/my probes when testing, so i do know there's juice somewhere!) i pulled the ignition switch, and it seems to be working - continuity at its pins change at all three switch positions.

so, where do i search now? again - turning the ignition key does absolutely nothing.

thanks,

doug s.

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BevHevSteve
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Re: '78 darmah - suddenly electrics completely dead

Post by BevHevSteve » Sat Sep 03, 2016 9:17 am

Do you have power to the switch?

Start at the battery and check power going away from it...

Pull ground strap and sand contact areas, install a start washer between strap and frame..
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doug s.
Cucciolo - the Lil Pup
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Re: '78 darmah - suddenly electrics completely dead

Post by doug s. » Sat Sep 03, 2016 3:31 pm

BevHevSteve wrote:Do you have power to the switch?

Start at the battery and check power going away from it...

Pull ground strap and sand contact areas, install a start washer between strap and frame..
ok... so this is interesting. and it's almost amusing, if it didn't take me a couple of hours to get it. so, (based on suggestions from another thread), i had already started checking power before i read your response. i pulled the seat, the tank, and the cluster of things under the steering head. i had power all the way to the fuse box. so, off come the handlebars again, so i can once again access the wires inside the "dashboard". i have 12.78v at the hot wire where it attaches to the connector plugged into the ignition switch! shite! power from the battery all the way to the switch! on a whim, i try one more test - probe on the connector itself; other probe to ground. AHA! NOTHING! i can't believe it, so i re-check the wire and the connector itself. sure enough - power at the wire, no power at the connector, wow!

check it out - the copper wires at the right of the connector were hot; zilch at the left side. complete corrosion block. i'm glad it happened when the bike was in the garage, and not at work last week, 30 miles from home.
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so, a new connector, button everything back up, and still time for a little 40 mile ride to the greasy spoon late this afternoon! :-D

thanks for the assistance; this site rocks!

doug s.

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Craig in France
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Re: '78 darmah - suddenly electrics completely dead

Post by Craig in France » Sun Sep 04, 2016 3:00 am

Your experience is very instructive, Doug. With these bikes now close to their 4th decade of existance, we should not be surprised if certain electrical connections aren't in the same state as when they left the factory :shock: .

'Word to the wise': check the connections at your reg/rec, if you haven't already done so ... ;).

P.s The connections inside the Nippon-Denso switches can also be getting nicely blackened by now ... :roll:. DAMHIK.

doug s.
Cucciolo - the Lil Pup
Posts: 3
Joined: Fri Sep 02, 2016 4:17 pm

Re: '78 darmah - suddenly electrics completely dead

Post by doug s. » Sun Sep 04, 2016 7:04 am

Craig in France wrote:Your experience is very instructive, Doug. With these bikes now close to their 4th decade of existance, we should not be surprised if certain electrical connections aren't in the same state as when they left the factory :shock: .

'Word to the wise': check the connections at your reg/rec, if you haven't already done so ... ;).

P.s The connections inside the Nippon-Denso switches can also be getting nicely blackened by now ... :roll:. DAMHIK.
yes, i squirted a silicone lubricant into every connector i came across, even before i got to the culprit. but now, i wonder if i should have gone further, and pulled each one open and checked it. :shock: oh well, it's back together, and at least better than it was before. if/when i have to do more electrical gremlin chasing, i may be more thorough. i think di-electric mismatch is the major culprit here; the bike has been parked in dry garages, for the ~20 years i have owned it.

doug s.

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