Topic: 12V Test Light

[7t1burb]

CB500/K2:

When the key is turned "ON" the 12V Test Light should be OFF until it reaches the "F" (for 5 degrees) to my understanding....however....12V Test Light is always "ON" (remains illuminated) regardless of Timing or Five Degree mark location.  Rotating crankshaft off "T" or "F" 12V Test Light remains ON....and I think it should go OFF until rotation of crankshaft around to the "F" mark.  This "LIGHT ALWAYS ON" situation is on both the YELLOW wire and BLUE wire of breaker contact plate??

Any insight?

Thanks
7t1burb

[Bob Wessner]

What are you using as a ground for the test light?

[7t1burb]

Test Light is grounded to engine case.....I went right "by the book" but this gremlin is stumping me....BTW I get a shock from a flashlight so as you can readily tell electrics are not my forte'..

[Bob Wessner]

electrics are not my forte'..

Mine either. What is the tune-up/running history? Was it ever running and you decided it was tune-up time, or is this part of an effort to get it going and it did not run before this? I'm assuming the points are set to spec. Do you see them opening and closing?

[7t1burb]

Was running 3 years ago per PO (who believes that?) and left dormant....have gone through all the wiring to eliminate corrosion, etc.  All electric connections check out with wiring diagram / continuity, etc.  Due to the "chuckle-head" PO who snipped off plug wires to add "look good" plug wires, I changed the coils from another K2 I had...those coils were good so I have eliminated "coil problems" for the present time.  I discovered this problem (no spark across points (both 1,4 & 2,3) when (in the dark) I could not see any "point gap spark" (with cover off) when I initially cranked it over a last week....

There is good continuity between the YELLOW of the contact plate and the YELLOW of the coil connection...same thing for the BLUE of the contact plate and BLUE of the coil connection.  I am puzzled where I'm getting the "power" from that keeps the light illuminated?

Each set of points is set at .014 on the high lobe.   

You help is really appreciated...

I'm beginning to believe that I may have somehow "hot wired" the contact plate when I was re-hooking up the harness...

[Bodi]

The points switch the yellow and blue wires to ground, the coils get +12V power through the ignition switch. The light should be connected across the points contact so when the points are open the light is drawing power through the coil; when closed the light is across a closed switch so there should be zero volts. You could also connect the light from battery + 12V to the points wire (not the plate) and the light will come ON with points closed and be OFF with points open.
It sounds like you either have misadjusted points or a wiring problem.
The coil black wires should have +12V from the battery only with the ignition key at ON and the kill switch on RUN. The coil coloured wires must go only to the points, if these wires are somehow grounded in the harness you will have no spark. Open the points - put some stout paper between the contacts - and check that the coloured coil wires (disconnected) are not connected to ground - you can use the test light from battery + to the wires for this test.
Since someone has been fu*king with the harness, anything is possible!

[7t1burb]

Thanks, Bodi

Off to garage to run the checks as you suggested..

Here's hoping!!

[Bodi]

Rereading your post, it sounds like your points never close. Might just be really really dirty! SOmetimes age and corrosion even get to the rivets that carry the juice to the spring, unlikely that both would be that bad though. Disconnect the coil coloured wire at the coil, turn the ignition on, and touch the coil wire to ground, like the coil mounting bracket or bolt. You should get a spark at the plugs (and the wire end) when you lift the wire off. That tests the coil and power wiring, if good you need to check the points and the wiring to them.

[TwoTired]

The points may have a thin oxidation layer across their faces, so they make mechanical contact, but not electrical contact.  Use fine emery cloth to remove this.  Don't use a silica bases abrasives as they embed into the soft point faces.  If you have a point or contact file, use that.

Cheers,

[Green550F]

I serviced the points on a completely coroded 350 last month. Since I plan on replacing the ignition later I decided to try cleaning the points for testing only(they're rally pitted bad!) So the radical cleaning proceedure involved the use of a Dremmel and a Stainless Steel wire brush tip.  Worked out so well, I may just keep those old pitted points for a while! 

Please note that this heap of S**T 350 still isn't on the road, and I wouldn't recommend too agressive a wheel to anyone wanting to keep their points... But the bike was free so what the hell!

[7t1burb]

Thank you to all who offered "help and insight" as to my recent electrical dilemma...PROBLEM IS NOW SOLVED!! and now am glad to report that the points were making mechanical contact, but no electrical contact(Bodi suggested this)...after a new set of points, off she went after some "coaxing"!!!  Not having run in 8 years, it was great to hear it fire off (with no exhaust), spit, sputter, cough and finally run.  Project Cafe Racer continues............
Again...thanks for everyones help!!
7T1Burb