No spark, how to diagnose... 86 FZ600

[ExecutivePowerNap]

Hey Guys!

So I've been lurking & reading other/older posts but feel like I should just ask myself:

Recently purchased an 86 FZ600, got to ride it once then it died 3 times on the way home.

Bought a multimeter - battery is good and its charging (when it runs).

Removed and thoroughly cleaned the carbs.

Fresh gas and fuel filter. Still nothing.

Will not start, but the few times it did, its dies soon after.

There's NO SPARK. My first guess is the ignition coils, but it seems like there's too many possibilities.

Basically I don't have a lot of money to just throw around, I'd like to know how/where to test and narrow it down.

Any help would be appreciated. I'll come shovel your driveway in the winter.

Thanks!!

Guenther

[Airhead]

Hi its important that the fuel tap is eliminated as being the problem, they are usually vacuum operated...does your tap have a 'prime' position?

[ExecutivePowerNap]

Yeah, eliminated that as I initially thought that was the problem. Yes there is a prime, which I used after reinstalling the carbs. Definitely spark problem not fuel, though why, I don't know....

[Airhead]

Yeah, eliminated that as I initially thought that was the problem. Yes there is a prime, which I used after reinstalling the carbs. Definitely spark problem not fuel, though why, I don't know....

If you dont know why its not fuel problem then why not eliminate this, the fact that it starts and then runs briefly could suggest va fuel problem. Why not pull off the fuel line and switch to prime to see if theres a good flow...could be just a drip...a partially blocked filter

[grizzlydan]

Hey Guys!

So I've been lurking & reading other/older posts but feel like I should just ask myself:

Recently purchased an 86 FZ600, got to ride it once then it died 3 times on the way home.

Bought a multimeter - battery is good and its charging (when it runs).

Removed and thoroughly cleaned the carbs.

Fresh gas and fuel filter. Still nothing.

Will not start, but the few times it did, its dies soon after.

There's NO SPARK. My first guess is the ignition coils, but it seems like there's too many possibilities.

Basically I don't have a lot of money to just throw around, I'd like to know how/where to test and narrow it down.

Any help would be appreciated. I'll come shovel your driveway in the winter.

Thanks!!

Guenther

Have you checked the plugs & caps, if they're knackered they start shorting out when warm. Also check all ignition connections for tightness & build up of verdigris (green powdery crap between the connections). You say there is no spark, how are you checking & if you do get a spark what colour is it? All these things need to looked at b4 you start spending major money on problems. I was lucky with mine when it started giving ignition & other electrical problems coz i'd just wrote off a XJ600 & replaced everything as all the electrics interfit. Don't know if you have one but I'd advise you to get a service manual. If only for the specs.

[ExecutivePowerNap]

Going back to the fuel thing - I removed the fuel line and put the end into a gas can and played with the switch to see what position did what, while in prime fuel was pouring out, so it seemed to work wonderfully.

Sorry - failed to mention that I already replaced the plugs. Not sure what you mean by the caps, they don't seem to have any - its the kind where the wire pushes straight onto the thread of the plug. I followed wiring here and there, but it such a mess (so many) its hard to pinpoint anything. Nothing is glaringly obvious. As far as checking for spark, I removed one plug (#1) and connected it with a wire and placed it against the side of the engine block = ground. Then watched it as I attempted to start it.

[Airhead]

So the fuel tap works well in prime, You dont know if it works in the other positions. I take it then that you are trying to run the bike then with the tap in prime position, are the plugs getting wet with fuel,

Also im concerned about the HT leads just being pushed on to the plugs without caps, this cant be right theres always some sort of proper termination like it shows on This Diagram Item number 23

[grizzlydan]

Going back to the fuel thing - I removed the fuel line and put the end into a gas can and played with the switch to see what position did what, while in prime fuel was pouring out, so it seemed to work wonderfully.

Sorry - failed to mention that I already replaced the plugs. Not sure what you mean by the caps, they don't seem to have any - its the kind where the wire pushes straight onto the thread of the plug. I followed wiring here and there, but it such a mess (so many) its hard to pinpoint anything. Nothing is glaringly obvious. As far as checking for spark, I removed one plug (#1) and connected it with a wire and placed it against the side of the engine block = ground. Then watched it as I attempted to start it.

well there ya go, looks like you've just answered the question to your own problem! No plug caps & the HTlead pushes onto the screw at the top of the plug. Which means the first 1/4 inch of HTlead has no wire in it & by shorting out the coil direct to the earth you probably burnt out the coil anyway. Meanwhile the way to check for a spark is to hold the end of the HTlead 6mm from earth & look for the spark. But hey what do I know I'm just a qualified motorcycle mechanic & also own a 1986 FZ600 so I think I know the difference. BUT then again I might just be qualified to not know what I'm talking about.

[ExecutivePowerNap]

OK, little update: Looked at the plug wires and by 'end caps' I guess you meant those little nubs inside the wire. They are all there. I thought you meant the little screw on parts (that's the technical term) that come with new plugs. I poked my multimeter in there trying to get some kind of reading came up with nothing. Not really sure how you check an end cap....

Checked coil resistance....2.7 ohms, right in the acceptable range. It did take a little poking around to get it which makes me wonder if I should clean those little terminals on top of the coil or if that would even help. They're not Hulk green, just a pale pastel hue.

So, yeah losin my mind a little. Last guess is its something in the wiring, which looks super duper fun trying to figure out.

Fuel is good, I promise. Where to start now????

[Airhead]

Can you post pictures of the plug caps?

[junker]

When i bought my 88 fz600 it would give me a "put-put" when trying to start and then would die... This was a symptom of the Pickup Coil (not Ignition Coil) being faulty. The P/U coil is under the first cover on the left side, closest to the front of the bike. Open that up and you will see a little teardrop shaped rotor that passes by two black diode looking things on a metal base. each one of those black things time the ignition for two cylinders. check the tiny metal part for any damage, this is another major issue with ignition. Also check the wires that lead from it to see if there is anything under the bike they are touching.

Another thing that could lead to there being no spark; is the ignitor box, when i bought my bike i noticed there was two IC Igniter Boxes, an older one in the under seat box. Maybe this is a common problem, so with your fancy-dancy multimeter, check the current of wires goin in and also OUT of Your IC Ignitor Box. It is Easy to find, It says; IC IGNITOR right on it...

I know what you mean by the wiring to be more fun than a barrel of monkeys to figure out! I have a really neat Kill Switch; When i turn the high beams on, it kills the bike! Got any tips for me?

-But the ignition wires don't seem to be in the main wiring harness thing, so they are relatively easy to trace, also wheck the wires between the Ignitor box and the ignition coils, and the unnecessary coupling plug for them half way down the wire.

GrizzlyDan-Chillax a little dude, he's trying his best man, i don't think he's trying to insult your intelligence or accomplishments, you helped me out a lot with other things, your a great problem solver.

[junker]

When i bought my 88 fz600 it would give me a "put-put" when trying to start and then would die... This was a symptom of the Pickup Coil (not Ignition Coil) being faulty. The P/U coil is under the first cover on the left side, closest to the front of the bike. Open that up and you will see a little teardrop shaped rotor that passes by two black diode looking things on a metal base. each one of those black things time the ignition for two cylinders. check the tiny metal part for any damage, this is another major issue with ignition. Also check the wires that lead from it to see if there is anything under the bike they are touching.

Another thing that could lead to there being no spark; is the ignitor box, when i bought my bike i noticed there was two IC Igniter Boxes, an older one in the under seat box. Maybe this is a common problem, so with your fancy-dancy multimeter, check the current of wires goin in and also OUT of Your IC Ignitor Box. It is Easy to find, It says; IC IGNITOR right on it...

I know what you mean by the wiring to be more fun than a barrel of monkeys to figure out! I have a really neat Kill Switch; When i turn the high beams on, it kills the bike! Got any tips for me?

-But the ignition wires don't seem to be in the main wiring harness thing, so they are relatively easy to trace, also wheck the wires between the Ignitor box and the ignition coils, and the unnecessary coupling plug for them half way down the wire.

GrizzlyDan-Chillax a little dude, he's trying his best man, i don't think he's trying to insult your intelligence or accomplishments, you helped me out a lot with other things, your a great problem solver.