1978 GS550 Contact Breaker Problem?

[tswirl]

I recently tested the ignition system on a gs550 that I am cafeing after a decade of neglect by the PO - http://www.thegsresources.com/_forum...d.php?t=197052

There is only a spark generated from the ignition coil for cylinders 1 and 4. I tested all 4 spark plugs and they work just fine and I swapped the coil for cylinders 2 and 3 with 1 and 4 and the same thing occurs so both coils are working properly. The white wire going to/in the contact breaker is the side at fault, the black wire is the side that works.

I consulted the Clymer manual for troubleshooting to no avail. I tested the circuit using a voltmeter from the +12v orange/white wire to the ignition coils and there is a constant ~12.3v from that to the ground, and slightly less from that orange/white wire to the black wire that goes to the contact breaker - however there is only ~5v to the white wire and it quickly fades down to a constant ~0.6v.

I'm not quite sure how to diagnose the problem here but I would like to avoid having to buy a new contact breaker (which appears to be perfectly clean).

[koolaid_kid]

Have you tried swapping condensers?

[tswirl]

When I went to take the condensers off, I noticed a considerable amount of white corrosion on the contact point for the white side, so I feel really stupid... :&

I'm gonna go scrape that crud off and see if it helps

[Redman]

See if it works with the condensor disconnected. If it does work with condensor disconnected, but doesnt work with condensor connected, then know the condensor is bad.
Condensor is not required for it to work. It may work without condensor but may also spark some across the points. Condensor is there to reduce how much it sparks across the points. So dont run too long without the condensor.
(this is my memory from years and years ago.)
(somebody tell me if I am wrong.)

.

[liberman.kevin]

RE: Contact Breaker Problem?

Hi I am having the exact problem with my mine. WHat have u concluded to be the problem with yours? I recently picked this 78 gs550 and has spark only on 1 & 4 coil pack , so i reversed the wires from 1 & 4 and plug them in to 2 & 3 and have spark, so I know both coil packs are good. Scratching head here , have u determined to be the culprit???any input would be appreciated thanks

[Big T]

new points and condensors, or a Dyna S, should be at the top of things to buy when you obtain a neglected bike