Ignition troubleshooting - coil test

83scrambler

New Member

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I believe these to be XS650 coils that I bought at a swap meet last fall. I am getting fuel and compression on both cylinders and I am unsure of the spark situation... hence the post.
So on to the measurements:

Continuity:
From brown to orange - 4.4ohms
From orange to mounting posts - open
From brown to mounting post - open
Brown to spark plug connection less wire and spark plug boot - 10.98 Kohms and 11.38 Kohms
Orange to spark plug connection less wire and spark plug boot - 11.37 Kohms and 11.37 Kohms
Orange to spark plug with wire and spark plug boot - 15.67 Kohms and 16.06 Kohms
Brown to spark plug with wire and spark plug boot - 15.66 Kohms and 16.06 Kohms

[/color]?? IMPORTANT ?? - You tell me...
I should note that the wires and spark plug boots are new, the boots are NGK 5 Kohm resistor boots. I have seen suggested somewhere here that another guy was directed to MikeXS for new yellow plug wires, screw on coil caps and the same coils that I think I have here. The spark plug boots that the gent was told to get were resistorless... Am I running into issues with the 5 Kohm NGK spark plug boots?
Continuing on,
I have gone through the static timing setup and have the points responding just as suggested.
After going through the above continuity test I started hooking things up, first:
1. Hooked up coils and condensor, both of which I verified a good ground.
2. Plugged Brown wires form each coil into the black w/ white double barrel connector
3. Plugged the left side coil orange wire into the yellow barrel plug connecting the coil to the left set of points
4. Plugged the right side coil Orange wire into the blue barrel plug connecting the coil to the right set of points
5. Rotated the engine to a point where each point was closed
6. Manually actuated the points on the left by separating them, I get a decent spark upon separation
7. Same with the Right, I get a decent spark upon separation
8. plug the spark plugs in to each spark plug boot
9. Ground the left spark plug threads against a good chassis ground and get a very weak spark down in the porcelain, not at the spark plug tip
10. Same with the right.Now what do I have wrong here? I have been looking at this very simple system for far too long and have done a lot of search only to fine tidbits of information, no full stories...
Please bring your suggestions!
Thanks!
 
ALRIGHT!

Luckily I have a CB350 in line to be gone through and it had plugs in it, I hooked that bike up to the battery charger and tested the point, they looked as if they were firing off well so I pulled the plugs and tested them by hitting the e-start and holding the plug against ground. The plugs both fired off really well. I then swapped them over to the project bike that I am having the troubles with and I got the bike to kick over and rev one or two times! So it is plug related! Prior to installing the plug i put the 5k ohm boots back on, so I'll leave those on for now.

My next concern is that the bike is a spark plug killer... what do you think could be happening there? After I got the bike to kick over I couldn't get it to kick over again. So I pulled the plugs and tested them out of the cyl head holding them both against ground. One still fired off and the other wouldn't do anything... Spark plug dead? I cleaned up the points on the plug with some abrasive cloth to no avail.

Any Ideas? I'll get some new plugs tomorrow, but I need to get to the bottom of the problem... Please shoot me your ideas!

Thanks, Justin
 
The sparking down inside was a dead giveaway that the plugs were dead. You appear to have fouled on. Get two new plugs and try again. Don't use too much choke.
 
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