CB 360 T ignition issues: Left Point grounded when open or closed.

C

Cursh

Loves Stock Airboxes
So my bike has been running rough for a while and I've been trouble shooting (for a while it was strong up to 5-6 grand and then fell on its face. - after that I had a spark plug eject itself - put in a sav-a-thread and reassembled today. set the timing by sight (watched for the points to open) instead of using a test light/ multimeter.)

Ran on one cylinder and the other cut in and out very sporadically.

Test the points/timing with my multimeter and the left points are grounded when both open and closed - unplug the points from the coil, and the problem is solved. Check the lead to the ignition coil with the condenser plugged in - grounded - unplug condenser - grounded.

So I'm seeing the left coil as always grounded and the right as always open (the right being what I expected)

I unplug the ground for the left coil and the problem ground goes away . . . so I'm guessing there is a short in my left coil . . . does this make sense?

Does this point to a bad coil? or is it something else? I don't really know how a coil works, so its hard for me to wrap my head around what I'm supposed to be getting when testing it with the multimeter (I'm basically testing on the OHM setting for continuity to a solid ground on the bike. IIRC - points are supposed to break continuity to the coils to trigger spark . . . probably using unicorn piss or something - who knows).

Thanks for your help. At this point I'm thinking of ordering a pair of replacement coils from DCC to hit this, but I don't want to fall into the old trap of throwing parts at it.

Thanks for the help
-Ben
 
To test the coils, check the primary leads- yellow to blue and yellow to black/white. Should be 4 - 5 ohms. Secondary lead is the plug wire to either primary. Should be around 10k ohms.
 
http://www.dotheton.com/forum/index.php?topic=53402.125
scroll down, look at picture, if your looks like that, it's wrong and will ground out.
Read replies and fit wires properly to points
 
In addition to what PJ said, I took a die grinder to the lower inside of my cover and then coated it with rubber insulation. Attwood makes a liquid electrical tape that you can paint on to the inside of the cover that you can get at any home improvement store or Walmart.
 
I was having that problem about a year ago, but I worked that out - the issue here is that the wire grounds out even when the cover is off and when the point wire is disconnected - traced the ground all the way back to where the bullet attaches to the coil.

I'm happy to hog out some material on the points cover though, that seems like it would simplify things - I was looking for new points wires because mine are looking a bit haggard, but I couldn't find anything. If the coils are bad, and I go with YAMAHAs, it might make the most sense to just build new points wires.
 
Set the gap by eye and not by light? Might go back and do it by light since the clearance when a point breaks is microscopic.

As far as the grounding issue, check to see if the screws that hold the points in are clear of the spring, if they are too large or you have the gap set wrong they can touch the spring.

Might test that point out of the housing if it keeps it up.
 
I guess what I didn't make clear was that I was using my multimeter as a stand in for a test light (set it to ohms and it will show you continuity pretty well).

Also - microscopic is a strong word for .13mm gap. You can absolutely see it (and my eyes are still pretty good with a strong set of unifocals on). I understand that in a best case scenario, you use all the tools available to you, but I'd lent my multimeter to a friend and was dealing with a rare situation where pittsburgh wasn't dumping rain on me non stop.

knock eyeballing if you want, but its helped me trouble shoot on the side of the road before and gotten me home in the end.
 
The points are fully open at .013mm....the opening of them occurs much sooner.... Gap affects the dwell as well as timing, but the timing is at the moment of opening, not at the largest gap.

You cannot set the timing by gap, as you have no idea where the timing plate is rotated. You could have the timing 30 degrees off, and still have the right gap.....

An old 12V light bulb and some wires can be used for rough timing, you don't need a multimeter.
 
I've used this guy maybe 100 times.
 

Attachments

  • TL.jpg
    TL.jpg
    56.2 KB · Views: 283
mydlyfkryzis said:
The points are fully open at .013mm....the opening of them occurs much sooner.... Gap affects the dwell as well as timing, but the timing is at the moment of opening, not at the largest gap.

You cannot set the timing by gap, as you have no idea where the timing plate is rotated. You could have the timing 30 degrees off, and still have the right gap.....

An old 12V light bulb and some wires can be used for rough timing, you don't need a multimeter.
Click to expand...

You have something wrong there, 0.13mm is about 0.005"?
Points gap should be 0.012"~0.016", I like to aim for 0.014" (fourteen thousandth of inch)
 
crazypj said:
Points gap should be 0.012"~0.016", I like to aim for 0.014" (fourteen thousandth of inch)
Click to expand...

I've always been advised to set for maximum gap- .016". Not sure the reasoning, but I've always just followed suit.
 
0.012" gives maximum coil charge time but quite often high rpm miss-fire. (longer dwell but more chance of points 'bounce')
0.016" gives slightly less dwell but bike runs better as long as points spring is good.
If spring has been overheated (ignition left on and points were closed allowing current to flow) you will have miss-fire problems
 
hey!

what did you find out? was it the coil? I'm having basically the same issue with a CB450.

when i set timing, the right cylinder is fine. when i test the left, nothing happens and the light pops on with the RIGHT marks.

when i disconnect the coil feed wires... everything is fine. -pretty much what you describe.

hoping you can tell me what you found to solve your issue.
 
yeah - the coil was bad. I picked up a better multimeter (digital self ranging innovovo or something for $19 on amazon) and it failed the continuity test.

its still too hot in tempe to work outside, so I'm just letting her sit until things cool down a bit. (should be caught back up with payments by then, and have some money to throw around as well).
 
i just put new points(honda oem) in my 350 a while back gapped them using the honda toolkit feeler gauge (aprx..015") then set full advance timing left cylinder,then checked right cylinder full advance and it was spot on
i did not do a static timing set it is a waste of time when just putting in new/replacing old points on a bike that was still running
the last time i did do a static timing set, after a full disassembly of the points plate from engine i just used a .0015" feeler gauge to adjust the timing plate to the "F" after setting both gaps, only necessary to static set for left cylinder
this assures the bike will start and run just fine for setting full advance with the timing strobe light
with this setting timing will be advanced so it must be corrected..
.
1000 miles later and the points gap has not closed up one lil bit
 
You must log in or register to reply here.

DTT Light or Dark

  • DTT Light
    • www.jadusmotorcycleparts.com
    www.lostapostle.ca/
    www.sparckmoto.com

    Spread the Love

    Back
    Top Bottom