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Hi folks, I've just bought a '69 CL350 that does not start. I've isolated the issue to no power at the left points. Wiring looks good tracing it back to the coils from the points so I don't think anything is disconnected there. It seems like the coils have been replaced at some time as they are both blue Tec brand units. The condenser also looks pretty new. I have power to the right side points. Where to go next please?
 

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66Sprint
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Need more information.... You will ONLY show power at the points IF the points are open.... If they are and still no power, that power would normally get there through the coil primary, so check power at the Black/white coil wire connection and check continuity through the coil primary (should be ~ 5 Ohms) and at juncture to the point wire....Somewhere there is a break in a wire......OR the condenser for that coil could be shorted to ground.....


You may phone if you wish....
 

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Discussion Starter #3
Thanks Sprint. The test procedure I used was to connect a test light between the power at the points and ground. Then I turned the engine over with the starter. The right side points flashed the test light as they opened and closed, as expected. However when I switched to left side and repeated there was no illumination. I'll chase wiring some more and report back.
 

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66Sprint
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Please post a picture of the points plate and points showing the wire connections to the tiny bolts...... I suspect that the left point is sequenced/stacked improperly resulting in a continuous ground connection......
Also, unplug left point wire from its coil, and measure voltage from that yellow coil wire to ground.....Should approximate battery voltage.....
 

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Discussion Starter #5
Here are two pictures of the points. I think it looks ok? No time to play with it today so the wiring testing will come soon.
IMG_8975.jpg

IMG_8976.jpg
 

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Your rocker pins have stamped marks that look like a T. The leg of the T is supposed to face outwards. Yours are facing in.
As for your power issue, maybe start where the points plug into (as mentioned above). If no power then check at the harness. Check you're not plugged into green.
 

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Discussion Starter #8
Thanks for the catch on the rocker pins. I'm still troubleshooting the no start which is likely no power to the left points. Will it be ok to leave the rocker pins as they are for the moment while I attempt to get the motor to run? I'll be checking all these things anyhow but wanted to concentrate on a running bike to begin.
 

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66Sprint
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NO....The secondary index on the "wrong" side of the eccentric adjustment "pins" alters the leverage angle of the rockers, and increases the pressure on the rockers and camshaft causing undue wear damage.......It also places the pressure on the valve stems off-center, likely increasing valve guide wear as well.....
Since valve clearance adjustment MUST be made on a stone-cold engine, NOW is the appropriate time to do it.......
 

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Discussion Starter #10
So the rocker pins have been rotated with a valve clearance check. Of course the clearances needed to be reset. Followed proper procedure for setting valves to turn the pins, rather than just rotating them willy nilly.

Re the points, I have continuity from the points to the condenser and from the condenser to the coil. It seems it is not a wiring issue. How to test other things like condenser and coil. If I switch wiring from one set of points to the other, the dead set work, and the live set do not. What's next?
 

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Discussion Starter #12 (Edited)
Thanks for the fast reply. I’ve disconnected the condensers, so coil only now, and no change. Power to right points, no power to left. Next?
 

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66Sprint
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Exactly!....Are BOTH coils Black with white stripe wires connected to the Black with white stripe dual connector from the main harness?

IF SO, unplug the yellow and blue points wires and verify power at the yellow and then the blue coil wires......
(Condensers and point wires disconnected)

IF YES at both colors, then either the "bad" point wire has a break in it or is grounded, OR the point to which it is attached remains grounded even when open.......

I can't be sure from the pics, but it looks like the solder joint on the yellow wire MAY be touching the points base plate and causing this ground....Pry it up/out a smidge.......
 

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Discussion Starter #17
I'm going to recap troubleshooting to date. The issue is no power to the left points. This is the yellow wire feeding power to that side.

- continuity of the yellow wire confirmed from points to condenser to coil: Good
- swap blue and yellow wires from points to condenser: power now at left points but nothing at right points
- put wires back in proper orientation and disconnect condensers from wiring harness, coils and points the only pieces in the circuit: no power at left points, power at right points
- put condensers back into the wiring harness, test black wire with white tracer which is power to the points: power at the spot where the two coils connect to the wiring harness
- left points are not shorting to ground because they have power when coil wiring is swapped.

So I am drawing some conclusions:

- there is power to both coils
- there is power to both condensers
- there is power coming out of the right coil
- there is no power coming out of the left coil,

therefore the left coil is defective.

How am I doing? Is there another test I can do to further confirm the left coil is bad?
 

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Have you tried just a multimeter on the coil wires and check for a break inside? Compare left and right. I’ve never checked that way but seems relevant
 

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Discussion Starter #20 (Edited)
Have you tried just a multimeter on the coil wires and check for a break inside? Compare left and right. I’ve never checked that way but seems relevant
Not sure that can be done here. There is an induction (or some such word) between the primary field (powered by battery) and secondary field (powering the spark plug lead) but there is no direct connection. I think the secondary field is only hot when the points open, though may not have the theory entirely correct... So not sure if there is a way to measure the "output" or resistance of the coil?
 
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