father in law helped to shed light on the problem

My father in law was in town today (will be for the rest of the week), and was able to help shed some light on the problem. We took the spark plugs out and tested them again. This time, I got a weak spark on #1 only, and the rest did not spark at all. There is most definitely fuel in the cylinder, and there appears to be compression in the cylinder as well (though his compression tool did not have an adapter to screw into my 12mm).

So we tested the thingy that powers the spark plugs (sorry, but I forget the name for it, so for future reference, I will call them "Bob"). It read 2.3 ohm resistance or so, and 10volts. My battery was reading 11 volts (I just bought a trickle charger and am currently charging my battery as we speak). I woudl think w/such voltage that it would at least spark my spark plugs, so we (to rule them out) bought new spark plugs and gapped them correctly (.028). Still no spark. When we opened up the side of the motorcycle where to power to "Bob" comes from. It reminded me of a distributor, with two metal pieces that were touched by this rotating thingy. It wa spining and all. He seems to think there is something wrong here, but I dunno.

Any suggestions? Spark plug wires maybe? I saw nothing wrong w/them. The cords are not dry rotted, and they appeared to be making proper connections to "Bob".... Does this help out with anything?

 

Good to have a second set of eyes on the problem, for sure.
The spark plug leads come from two "Bobs" aka Ignition coils. They are triggered by the signal from the rotor & switch assembly under the cover on the left side of the engine. When the rotor trigger lines up with the plate switch, it sends a signal to the ICM (Ignition Control Module) which measures a few other parameters and then triggers the ignition coil to fire Two Cylinders - One fires at the correct time for ignition in the Power stroke, the other wastes a spark in the companion cylinder at the top of the exhaust stroke. Cyl 1 & 4 should fire together at Every Revolution Likewise Cyl. 2 & 3.
If you have one plug sparking, That most likely means that coil is good, Take the angle boots off of the spark plug leads (they unscrew) & check for a poor connection there. Corrosion is likely. You can try to trim a small amount from the end to where you can see bare wire in the center. but check to make sure the leads will still reach the plug!
Then switch spark plugs & make sure they are well grounded when you test them.

 

Well, the one WAS sparking, but is no more. I can't get a spark on any of them. What voltage should I read on the ignition coils?

 

The coil wires can be measured also. Remove the plug caps and check the resistance. Should get around 11Kohms. The plug caps have a resistance also. Most are 5Kohms, some are 8kohms. If these check out good then I would suspect the TCI.

 

You should be getting battery voltage at the ignition coils - 12 volts or pretty darn close to it!

 

The TCI?

 

I think you need to get in touch with your bike and learn what all the parts are! Here's a good link on electrical stuff you should go over....
http://www.geocities.com/MotorCity/Speedway/7795/

Your bike basically has an electronic ignition system. The side cover with the "two metal pieces" are your pick up coils. As the rotor "rotating thingy" spins, it energizes each pick up coil that sends a timing signal to the transistor controlled ignition or TCI. The TCI then sends a signal to the coils "bob" which then fire the plugs.

On these bikes the starter doesn't need much to get it to spin, but it may take all the battery has to offer and leave nothing for the ignition to fire properly. It's important to have a good battery charge to get the bike to run.

A few other problems on these bikes:
1. Your fuse panel, if original equipment is very prone to failure.
2. Check your alternator brushes, if worn out will not be able to charge the battery and you will constantly have problems.
3. If the bike has been sitting for a long period of time you really really need to get the carbs cleaned thoroughly. There are screens on the top of each float valve that could clog. The float needles may not be sealing. The float level needs to be adjusted correctly. The butterfly shaft seals could be hard, cracked, and no longer functioning.

 

I never claimed to be a pro here. I know I need to know the parts by name.

Thank you, this looks like a great source of info for me.

As for number one, the fuse box looks relatively new compared to the rest of the bike, but since they are fairly cheap, I am in the hunt for a new fuse box as we speak (I believe someone suggested radio shack?). As for number 2, I am on to that after the 4th. I have a suspicion that they might be going bad, and may have attributed to the low volts on the battery I have in it right now, though that could be just from trying to get it started and constantly cranking it. Finally, number 3, the bike was running w/o a problem just 4 days ago. I had removed the carbs yesterday and while having them removed, I looked and they appear to be clean, though I did not open them up to view the screens. However, considering that the bike was not giving me any problems just a week ago I assume my carbs are currently clean. However, taking them out, and reading over tutorials on how to clean them here is getting me in the know for what to do next spring.

Regardless, I am no mechanic by far. I bought this bike for two fold reasons - one, because I needed cheap transportation from one end of town to the other, and enjoy riding a bike - two, because I want to know how to fix engines and a basic understanding of them. I know that some of my questions seem rather stupid or just ignorant, but I am learning so much from this.... its been a great thing.

 

Kish:

You're doing fine. Knock-off one issue at a time, and do it right.
If you "Rig-up" something, just to get that thing out-in-traffic ... the hastily done fix might decide to fail you, at an inopportune moment, and that could be real bad news.

Finish-up your "Signature Thumbs"

Year -- Model -- Miles -- Stock/Modified -- Current major issue (1).

 

So, if I need two ignition coils (not sure just yet), then are their aftermarket coils I can buy, or do I need to find them on a junked xj550?

 

You need to read this thread:
http://xjbikes.com/Forums/viewtopic/t=5 ... ition.html examine the drawing, then get a meter & check the coils you have.
Only then will you know if you need another set of coils.
I doubt it.

Have you checked for corrosion where the caps attach to the ignition coil leads? What did you find?

regarding names of components, each of us may use different names for the same part. Such as my term ICU (Ignition Control Unit) describes the same part as TCI box (Transistor Control Ignition) box. When I talk of Ignition coils I mean the large round cans with leads that go to the spark plugs. Others call the switches on the timing plate "coils" but I prefer the switch terminology to avoid confusion. They switch the ICU on at the right time so it can fire the ignition coils

 

35,000 Miles, Brother ...

That's PRIME Alternator Brush shortness time.

Get in there and measure.

 

Hey, if my alternator is bad because of the brushes, but my battery is charged up, shouldn't it still fire for me at least? I am getting no fire what so ever right now...

 

Follow-up: So I got a multimeter and tested my coils. I get a reading when I test from the two lead wires into the coil (approx 2.5 ohms or so), but I do not get a reading when trying to read from one cap to the next. The caps are very clean w/o any corrosion on them.

The thing that has me going is this - if my coils went bad, why did both of them go bad at the same time? That makes no sense to me.

 

Me too, tested both coils. Got about 3.5 ohms reading from both at the terminal but none at caps. Yet, they still fire... Maybe starting going bad or I did the testing wrong (I did follow the manual).

Sorry not much of help here but just letting you know you're not alone in the boat.

 

Yeah, but your's still fires. Mine don't at all....

 

Okay, so I put a brand new, fully charged battery into it and I get a very very weak spark now. Ripping open the alternator is my next thing to do (once my wife comes back so she can watch my children while I do this). With a battery showing 11 volts of charge I get no spark. With a full charge (12 volts) I get a weak spark. Shouldn't I get enough spark to start my engine w/a fully charged battery, w/or w/o an alternator?

 

The plug caps should be off when your testing your coils. Here's a copy from the web link I gave you on testing coils......

You can check the secondary resistance of each coil by removing the plug-caps (they screw off) and measuring the resistance between the ends of the two plug wires. The specification is 11k Ohms.

A low resistance measurement indicates an internal short in the coil, and results in diminished spark. A high resistance measurement also diminishes spark somewhat. An open circuit between the plug wires means a wire is broken, either a plug wire or an internal coil wire.

[A coil may still operate with an open circuit secondary. The voltage spike jumps the broken wire (another spark), in addition to sparking the two plugs. In some cases, its possible to ride for a number of years with an internal broken wire!]

 

"Stuff" the ends of the Spark Plug Wires for a Test.

Strip some wire and Twist it tight.
Insert the bare wire as far as you can into the ends of the Spark Plug leads after unscrewing the Plug Caps.

Stuff it real good ... the, Twist-on the Plug Caps ... TIGHT.

If you fire-up ... its the wires. (Which are hermetically sealed in the Coils and may be replaced with the "Coil Surgery Procedure" which I tried and gave-up on.

 

Let's be clear: BAD ALTERNATOR BRUSHES WILL NOT KEEP YOUR PLUGS FROM FIRING. Bad alternator brushes will result in not charging the battery and the low voltage from the battery may prevent firing. After you charge the battery the plugs should fire even if you have removed the alternator from the bike!

11 volts is WAY low. Normal charged voltage for your battery is 13.8 volts. It's considered discharged well above 12 volts. If it's been sitting around discharged it is likely ruined.

So, let's eliminate one thing at a time:

1) Pull the tank and look at all you connections. Unplug the coils from the harness. Everything clean and tight? Plug them back in.

2) I helped WarDog12 with a similar problem on his 550. The bike would crank but no spark - all plugs. Turned out to be a corroded connection on his kill switch. Pull it off and have a look at it. There is a connector on the RH side of the frame under the tank near the front tank mount. This is where the kill switch connects to the harness. Make sure it is clean and tight.

3) Have a real close look at the fuses and panel. It's not important if the fuses look good, are they tight in the connectors and is there 0 resistance across the panel wire to wire?

4) Get some power to it. Check fluid in your battery, top off with distilled water if necessary. Hook up to your car battery with jumper cables. Do it with car and motorcyle turned off. Make last connection to the (-) on the car battery - if you've shorted a cell on the cycle battery it's possible it will explode. Leave car turned off and crank the bike. That car battery has enough capacity to crank your motorcycle all day.

Now, if you still don't have spark we'll start looking into the components.

 

Let's be clear: BAD ALTERNATOR BRUSHES WILL NOT KEEP YOUR PLUGS FROM FIRING. Bad alternator brushes will result in not charging the battery and the low voltage from the battery may prevent firing.
. . . . . . . . . .

Therefore:

Bad Brushes WILL effect Ignition.
You actually just said so ... yourself.

The battery (system) needs to be supplied a constant voltage.

Without an Alternator ... the bike will start ... sure.
But you'll be pushing it home in a few minutes ... huh?

Where DOES a healthy electrical system begin?
With a Good battery.
That stays charged.
By the device which supplies the charging current.

 

Rick: I have no doubt that my alternator brushes need replacing (hell... its so cheap, why not?)... You bring up a good point that the mileage on my bike demands I replace them; however, my current problem is to troubleshoot the bike and find what is causing it not to even fire now. Once solved, then the brushes are next. With any luck, this will be my year round bike. Only time will tell.

 

Rick, you get no disagreement from me on the importance of a healthy charging system.

My point simply is he can work on the charging system until the cows come home and this bike will still not start. He has a problem on the ignition side which needs to be corrected. And he for sure has a very dead battery.

Is the battery dead from alternator brushes? Maybe. It could also be dead because it is at the end of it's life, the rectifier could be shot, the connector from the stator to the harness could be burned to a crisp, the stator could be bad, there could be a short somewhere draining it or it could be just plain cranked to death.

We also know that the vast majority of ignition issues (all electrical issues really) are due to deteriorating connectors and switches on these old bikes. I'm simply suggesting that the OP tackle the most likely causes first.

Should he check his alternator brushes? Absolutely! He should do all the Preventative Maintenance on his bike. Plus the stuff that's not in the PM schedule like getting the gunk out of the brake lines, replacing his fuse panel and checking the connector from the stator to the harness that causes many charging issues.

 

My battery is not dead. It is fully charged using the charger I have (12 volts)....

 

Shoot some WD-40 into the Ignition Switch.
Remove the Left side Crank Cover.
Rotate the Ignition Rotor mid-way between the Ignition Pick-ups
Clean the Pick-up's with Soft Bristle toothbrush and Electronic Parts Spray Cleaner.

Trace Pick-ups pigtail to wire harness connection. Under or behind airbox.
Disconnect from harness.
Clean contacts.
Replace
Disconnect Ignition Module from Harness
Clean all contacts with Spray Electronic Parts Cleaner

Clean Coils Contacts to Coils and Harness

Remove Headlamp

Clean Ign & Switch pigtail connections to harness

Test Ign & Switch pigtails for 12V, Open/Closed and look for Orphan Wires not plugged-in.

Place transmission in NEUTRAL

Disconnect Safety Relay

Cut-off the Head of a Live Rooster and encircle the bike with its blood

Fire that Mother UP!

 

What's the "ignition switch"?

 

At the bottom of the ignition cylinder (where you stick the key to turn the power on) is a switch that controls main power sent to the branches of the fuse box. It can become dirty or corroded. An occasional cleaning is a good idea. It can be linked to a "no start" condition, but so can a few other things. Just clean it and eliminate it from your list of possibilities.