need help please.

hey everybody brand new member..and i have had my 1983 xj 750 maxim for about 7 months now. got the bike from Craigslist for 700.00. because it had an electrical problem. so i started going through it and found some bad connections and a few bad relays and put it back together cleaned all the carbs well and she ran like a dream. did start to notice intermittent problem occasionally it would crank and crank but would not start so i would bump start it and it would fire right up. it was an occasional problem until last week. then it wouldn't start at all. so i did some testing and found my left ignition coil was bad. bought a new aftermarket set hooked them up and... still no spark.back to testing again..this time i found that one of my pick up coil was burt, as when i ohm it out O.L. so i replaced that and now she starts and runs.. but only on the left coil cylinders 1&4. i have power all the way from the pick up coil through the tci box to the right coil but does not spark at the plug so i am thinking the tci box is bad..but i am definitely open to any suggestions or help. thank you very much in advance.

 

Re: nedd help please.

Swap the left and right coil plugs from the TCI and see if you get spark at the left and right coil when turning it over. (dont leave the wires connected to the plugs still in the engine since you would be firing the right coil when the left should fire) If the left coil stops sparking and the right coil starts sparking then it would sound about like a TCI issue. Dont forget to put the wires back to original after you test for spark on both sides.

 

Re: nedd help please.

my fault i forgot to mention that was suggested on one of the other forums which i did perform and i got the right coil to spark and no left coil spark, another tidbit, when i switched the low tension leads back i put my volt meter on the 12v lead from the harness at the tci all the way to the coil and i get twelve volt does this also suggest a burnt channel in the tci? with the ignition switched to the on position.

 

I would likely fault either the TCI or the pickup coil. Being that one of the pickup coils was burnt it might not be bad to check the other one. Another thing to do would be to check the primary and secondary coil resistance of the old coil. I dont know the specs offhand but they are listed in the forum if you look about. Being that the coil does fire with the wires swapped the coil its self is likely OK though. Maby swap the pickup coil wires if you can and see if you get spark on the right coil and lose it on the left also? If that seems to be the case then I would probably blame the other pickup coil over the TCI. If the wires cant be swapped I dont know the exact testing procedure for the pickup coils but looking around will likely turn up the procedure for those as well.

 

i had the same idea so in the mean time i verified the other pick up coil and it checks ok.the resistance test are the only ones that i know of for the ignition and pick up coils i think its +\-20% of 11,000 ohm on the ignition coil high tension leads and +\- 10% of 750 ohms on the pick up coils. According to my manual. also there is the pull the plug and ground to the engine with plug in cap....is there any other way to verify that my tci is at fault? and if so is a used ebay one my best bet? the other option that i know of is to rebuild it or purchase an aftermarket. because the new old stock Yamaha has they want upwards of 700.00 for? by the way Thank you in for all your help and time. this is my first day as an official member and it is awesome.