QuestionDear Bill,
I am not getting a spark on my left cylinder (twin). Obviously this
is an electrical problem, but I believe it happened after I was
replacing some taillight bulbs and may have not grounded
properly. I think it was the left rear turn signal that I had
replaced and it worked fine for a minute, then i noticed the wire
to it getting hot and then nothing. That's not the problem
though. What stumps me though, is what did I do or what
happened. I tried different plugs and checked for a spark in the
dark and there is none (except for an occasional and random
pop for every minute or so that i am constantly cranking). And
there is no arcing happening. So, is it possible I just blew a coil
or condenser? I am trying to find a mechanic but it's tough and
scary. Can you please help me at least go into the whole ordeal
with a clue? Thanks so much!
Sincerely,
Schuyler Klaassen
AnswerSchuyler.... Your tail light bulb problem is not related to the coil problem unless you are shorting out the battery with the tail light and the voltage is too low to fire the coils properly. DO find and fix the light problem. HOT wires are not a good thing. Be sure that you are using the proper bulb for the tail light 1157 should be sufficient. The turn signal bulbs are single filament, so require a different bulb. The green wires should all be securely connected for the ground path to make the lights work, otherwise, there will be "feedback" through other bulb circuits and the lights won't work.
Next, be sure that your battery is fully charged before you venture into the ignition system.
The most common problem with having no spark is that the points are dirty and not making good contact. Get a small point file or some fine emery cloth to scrub the faces of the points clean. Be sure that there is no grit left behind to keep them from closing fully. Use some contact cleaner to be sure. The maximum gap of the points should be .012-.014" fully opened on the point cam. The point cam should be lubricated, as well. Generally, I suggest that the point plate be removed (put a scratch mark at the edge so you can get it back close to where it was), so you can inspect the spark advancer, making sure that it is allowed to fully advance and retard w/o assistance. If it is sticking, the retaining bolt/washer has to be removed from the end of the camshaft and the mechanism disassembled, cleaned and lightly lubricated with lithium grease or point grease if you can find it at auto parts stores now. BE SURE to mark the point cam before you slide it off the end of the advancer, as it will go back TWO ways and one will not allow the engine to run.
Once that is done properly, put a LIGHT coat of point cam grease on the point cam, reinstall the point plate where it was marked and then check the point gaps. After that, with the bike on the center stand, you have to remove the dyno cover...put a pan underneath the engine because there is oil inside. Use a wrench to turn the engine over slowly and watch the points open and close. With either a 12v test light or volt meter, turn the ignition on and watch when the points open and close. The meter or light should show this clearly. IF you get differences from one side to the other, then the points are still not closing OR the condenser has failed on one side. Generally, the side with a bad condenser will ARC heavily when you turn it over and the point faces will have HEAVY pitting. The condenser pack is up with the coils under the fuel tank. They are packaged 2:1 so you have to replace the pair of them together. Check ebay for some cheap ones, as HONDA wants a stupid amount of money for them. Or check m/c salvage yards.
The points will open at the F and LF marks when properly set. Do the left side first, moving the point plate to adjust the point opening time. If the right points do not have a separate base adjustment, then you can open/close the point set slightly to change the point open time. Once the timing is set properly, then you should have a good sparkk on both plugs. Use new ones to test, as old fouled ones that will short out internally it it will appear that you have no spark still. The spark plug caps can also go bad, so unscrew them from the wire end and check the resistance with an ohm meter. If they are close to each other... around 5-10K ohms, then replace the caps.
You can leave the point cover off when the engine is running and watch the points for arcing issues.
When you put the dyno cover back on recheck the oil level to be sure that it isn't too low after the cover was removed.
If this is all GREEK to you and you don't have the tools or confidence, then let someone with experience do the work. You have your clues....
Bill Silver
