No spark after ignition coil replacement

[ScottBowl]

Greetings, gentlemen! This site has proven incredibly useful thus far, but at this point I feel I must reach out for help.

I bought an '83 heritage special. She was running good (albeit just a tad rich) but then a few weeks later, she started sputtering and generally sounded not very happy. After some troubleshooting I figured the ignition coils were done, due the ignition coils being reportedly known to fail. I tested it and sure enough, the readings were not up to par.

So I install the new ignition coil, and now it won't spark! Okay, so what else could it be?

• Checked fuses
• Battery voltage good, fully charged
• Checked grounds
• Tested stator/rotor, good ohms reading
• tested ignition coil, (maybe it was DOA?) good readings
• Brand new spark plugs installed

Still no spark

Then, upon further investigation, I learn that the CDI units on these bikes are pretty terrible. Problem is, I can't seem to find it on my bike, and even if I did I can't find instructions anywhere on how to test it. Apologies, I am very un-knowledgeable with this kind of stuff.

Any help would be greatly appreciated... Riding season is almost over

EDIT: I am NOT using the "high tension plug wires" as mentionned in the catalogue for the ignition coils. Could this be my problem???

 

[riksoto]

Here are a few very good links to the info you are looking for

http://www.xs650.com/forum/showthread.php?t=3289
http://www.jetav8r.com/Vision/IgnitionFaq.pdf
V/R
Riksoto

 

[xjwmx]

Then, upon further investigation, I learn that the CDI units on these bikes are pretty terrible. Problem is, I can't seem to find it on my bike

It's a TCI, technically, and it's actually about the least troublesome ignition for these bikes out there. Where it is is on the bottom of the battery box. You ordered the right coil for the TCI, but you are mentioning coils, as in plural?

Put the old coil back temporarily and see what happens. Did you have the original coil still on it? What did you do for plug wires? Did the old coil measure bad? Why did you suspect it?

 

[aldo5468]

I have the same problem at the moment - brand new coil, spark plug wires and NGK 5K boots but no spark. Besides the TCI "black box", the other component in the ignition system is the pickup mounted to the stator - the pickup is what generates the signal that the TCI box "processes" and sends on to the coil to fire the plugs. If the pickup coil wiring is open or shorted internally, the TCI will not get the correct input.

 

[xjwmx]

I did have a pickup coil go open and I had to replace it. They gray wire was open. It would still spark, but not at the right time and it wouldn't start. Worth the easy check - coincidences do happen....

 

[XSLeo]

If you have a repair manual it will have the test procedures and specs you need to test your ignition.
Get one.
Leo

 

[riksoto]

Here is a link to a free pdf manual Yamaha factory manual
http://biker.net/650_service/650service main.html
http://biker.net/650_service/650_svc_gsg.PDF
Pg 9 has a trouble shooting tree

Riksoto

 

[Purplezinger]

If you have an
83 with factory ignition, there is only one coil. It is dual output coil with 2 spark plug leads. What did you replace it with?

 

[Paulrxs650]

Scotbowl, change your plug leads - I had a very similar problem recently and went right round the houses til I worked out the problem!

 

[ScottBowl]

Everyone, thank you so much for the quick replies.

You ordered the right coil for the TCI, but you are mentioning coils, as in plural?

My apologies. The coil is a single, dual-output unit, not multiple coils (as found on older xs650s)

Put the old coil back temporarily and see what happens. Did you have the original coil still on it? What did you do for plug wires? Did the old coil measure bad? Why did you suspect it?

I had the new coil on the bike. I used the same plug wires that were on the old coil. The old coil DID measure bad, and that is why I replaced it.

Scotbowl, change your plug leads - I had a very similar problem recently and went right round the houses til I worked out the problem!

Will do!

I am going to test the pick-up coil to see if it is within specifications (this is the small piece at 12 o'clock on the rotor, correct?) and check the wiring to make sure there are no shorts. Thanks again, will update when I have news.

 

[ScottBowl]

Update:

We got to the TCI and after opening the box the first thing we noticed is that someone had been in there before us. We saw one capacitor that was very, very loose and was surrounded by hot glue (what the fuck?). We figured the glue was to prevent moisture from getting into the capacitor, but they sure did a terrible job, it looked like a mess.

The board after cleaning it up

This little guy was the culprit

And this is his home

Underside of the board

Questions:
Should I replace the capacitor? Any reason to believe that it's bad/how can I test it?
Does anyone see any connections that are bad and need to be re-soldered?

Thanks again for your help!

 

[scabber]

The solder joint above the right side bottom mounting hole looks like it could need a resolder. I would replace the glued in part. Someone here probably knows how to test it.

 

[wallywheels]

I to need the same capacitor in my ignition box has anyone discovered where to get it and some details on what the part is?

 

[xjwmx]

Interesting. Was the capacitor loose? It probably just needs soldered back, but it's about a 25 cents to replace (Radio Shack).

That board only looks bad to the untrained eye The hot melt is there to keep the tall components from breaking off from vibration. It's factory.

 

[wallywheels]

capacitor was burnt up as charging system got to a very high voltage. The charging system has been fixed but I found the capacitors on digikey.com for what you said I also ordered another part that is bubbled up inside the tci box which was 1.58 each hopefully I can save the board otherwise everything looks fine inside I tested a different TCI box and bike ran fine

 

[wallywheels]

Also I know the hot melt is supposed to be there I have done some work on circuit boards in the past and I sometimes use hot glue to keep things form rattling around inside them. Thank you for the help though I will do an update if this fixes the TCI unit I know its the issue because I have spares laying around and I just want to try fixing this one for haha's. I just wasn't sure if it was anything special or a simple capacitor. Thanks again

 

[xjwmx]

When it comes time to test it, just plug it in on the left side and let it hang.