After all these many years, My bike suddenly has begun to be plagued with problems. Currently, I have spark problems with my 1980 Honda CB750K, The ignition coil in question, is for cylinders 1 and 4. I removed it from the bike frame, where, I discovered a long crack in the plastic housing of the coil. Whether that will cause it to malfunction I do not know. the engine is missing terribly, and idling is very difficult till the engine is warm.
At idol my timing light shows the coil for cylinders 1 and 4 is very inconsistent. firing every now and then....would this point to a bad ignition coil or something else? Like the spark units? mine look like they may have melted goo from their back sides...how do i test these?
I decided to assume the coil to be bad, and hunted a replacement..I found one used but said to be good. I installed the new coil and unfortunately, the bike runs just the same rrrrrrr!
I have looked at my spark units and they have the appearance of the back sides having melted. I assume then that is not good??
The question remains, what would cause these spark units to over heat and melt? a malfunctioning component some where in line? or Are they located in an area where there is not enough air circulating around them, i wonder?
I am also trying to test the pulse generator pick up coils down on the motor...but I have no specs. to compare my readings to or to know for sure I am testing the correct wires or in the correct manor..rrrrr! but, my readings are as follows:
the pulse generator coil, resistance is
517 ohms for cylinders No. 1 and 4
and 533 ohms for No. 2 and 4
I also assumed there must be voltage created from the pulse generator when the engine is turned over by the starter...so I attempted to read any voltage, generated from it. so I attached my meter's leads to what I am assuming is the pulse generator pick up coil leads.
there are 3 paired wires, two yellow two blue, and a Green with red and a blue with red tracer
When the engine is cranked, the highest readings are as follows: with Meter reading DC Voltage and set to scale of 4Volts.
between the yellow wires: .040 then drops off
between the blues 0.45 and then drops off
between the green/ red tracer, and blue with red tracer: 0.23 then drops off
Another problem I don't know if these readings are good or bad, and if I am testing correctly?
I have searched so many nights for a web site / group for Honda DOHC owners and find none! I do hope you SOC fans, won't mind me asking for help / guidance for my DOHC, I don't know where to turn otherwise.
I'll watch for your replies. thanks so much for any tips and assistance.
David
10-22-07
