no spark....HELP!!!

[DonTZ125]

Guys, you're giving me a headache. Actually, I already have a headache, and this ain't helping.

Most of what is being bandied about would be true if the FZR ignition was CDI. It isn't. The FZRs use TCI:

• The coils are powered full-time by the key switch. A voltmeter will register battery voltage right up to the TCI (up to the collector pin of the coil driver transistors, if you want to get pedantic).
  The TCI / ignitor is powered by the kill switch (via the key switch, obviously).
  The TCI charges the primary side of one of the coils by turning on the appropriate coil driver transistor, GROUNDING the coil via the Orange (1-4) or Grey (2-3) wire. This allows current to flow for ~2-3 milliseconds, building the coil magnetic field. The transistor is then turned OFF, stopping the flow of current. The field collapses much faster than it built, sending a substantial "flyback" voltage spike through the secondary coil and so to the spark plugs.

A CDI pumps power FROM the ignitor TO the primary coil to ground. A TCI *allows* power from the battery to the coil to the TCI to ground. Very different principles of operation, and significantly different wiring and components.

Hunter - take a look at this wiki article, go through it carefully. It won't spark - now what?

The crank pickup coil is a variable reluctor; a lump of iron with a wire wrapped around it, it generates an oddly-shaped AC signal when a lump of ferrous metal (in this case a 'tooth' on the alternator rotor) goes passing by. The shape and frequency of this signal is what tells the TCI what the crank is doing. The values mentioned sound like it's in spec, and it should most definitely have infinite ohms relative to battery ground. Hunter, you had mentioned that you had a DC reading across the pickup's wires; please check that and confirm.

[hunter_1_2_3]

I got mine off a friends neighbors, he had it locked n a garage for bout 7 years, with big plans but all he did was do a shitty paint job, mess with the wiring and block the carbs. After I got it running an wiring fixed I realized it wasn't chargin so I got r6 regulator and fitted it, nice nu paint job, tyres and service but just when i put carbs back on... No go, but it's getting juice... Well was b4 pump gave up but the bikes near 20 yrs old an I'd rather it get changed now than when I'm out bout 50miles from home an it won't start. Wat goes in the tci boxes usually, r there ny tel tales when they go? What's cheapest option, repair or 2nd hand?

[hunter_1_2_3]

Cheers don will read over that wiki thing and check them things tomorrow, sorry bout the hassle boys I'm a newbie when it comes to these forums, thanks for ur patience.

[DonTZ125]

Hunter - one more thing if you could: Write in English, not LOLCatz, or MS-Speak, or whatever. It took me 3 tries to read and understand the last sentence about TCI failures in your post above. When you're asking technical questions and expecting technical replies, clarity of communication is critical.

[hunter_1_2_3]

Plug cap resistance for each one was 4k ohms. And resistance between leads was infinity, so I think im onto something, is it possible for both coils to go? Are there any common faults on these bikes that would burn out the ignition coils?

[hunter_1_2_3]

primary resistance for each coil is 2.8-3.0 ohms would that be enough to stop it sparking?

[hunter_1_2_3]

Would anyone agree the resistance between ht leads should not be infinity? what would cause both coils to go suddenly?

[SouthendChris]

Primary resistance - as in between the two wires in the connector block of the coil?? The service manual for the FZR600W/WC I have says 2ohms plus or minus 10%.

The secondary resistance is higher, alot higher. You will have to change the range of your multimeter upwards or it will show 'infinity' but actually just be above the scale you have it currently set to. A service manual I have shows FZR600W/WC coil secondary resistance (between HT leads with caps off) off 9600ohms and 14400ohms. The caps are supposed to be 10000ohms each.

These valus may be different on a UK model bike.......

I personally think you need to borrow a second ignition black box to see if yours is faulty.

Chris

[DonTZ125]

Measuring the resistance between wires 1&2 will (hopefully!) give infinity. You have to measure between 1&4, 2&3. A pulled-off (but still looks in place) plug cap will show as an open circuit, as will a shattered resistor inside the cap, as will a broken (inside the insulation) HT wire.

+1 to Chris' comment about the range - if you switch from measuring the primary to the secondary without changing the range on the meter (mine auto-ranges, so I'm spoiled, but earlier / cheaper models don't) will show an open circuit.

[hunter_1_2_3]

well i measured the primary resistance (red/white to grey and orange) wires and i got 2.8 - 3.0 ohms on my draper multi meter. i measured secondary resistance between the leads 1+4 / 2+3 and according to the wiki no start thing you sent me don, i should be getting between 9.6k - 14.4k ohms, i was just getting infinity and this was with the multi meter range changed. the plug caps were givin me 4k ohms for each one. like i said i was getting my (what it should be results) from the fzr haynes manual and the wiki link, the fact i was getting infinity between the leads was concerning but i still dont understand how they could both just go together as quick as that, seems highly unlikely. the pickup coil resistance results i took the other day were definatley in the ball park compared to what they should be according to the service manual so im assuming its alright. i rang around the local garages and scrap yards but no one has a tci box to try, so at the moment im a bit stuck and funds are a bit low because ive been restoring this bike for a few months now piece by piece.

[hunter_1_2_3]

Hi I just wanna say thanks for the help Iv got, but iv still been having a bit of trouble, unfortunately since i last spoke I have changed the fuel pump and pickup coil and stator, I still dont have a spark at either of the ignition coils, I'm now thinking cdi/tci box, I have had the box open and everything looks good (no corrosion or burns) . The fuel pump is working properly, is it at all possible for the tci box to stop sending a signal to both coils, rather than just one failing?

[DonTZ125]

Hi, Hunter.

It indeed possible for both driver transistors to fail, and even possible for them to fail with no outward signs (they do usually fail rather obviously, though). The fact that the fuel pump comes on is a very good sign as far as the processor itself goes. Before you start tearing into the TCI, though, I would suggest one final pass through the safety system - do you have continuity to ground at the top-center pin on the 6-pin connector (bLue/Yellow wire)? No "ground" signal at that pin means no spark. Actually - if you can, try jumping that pin to ground (lower left pin on the 6-pin connector, or straight to the battery -ve post), and see what happens.

[hunter_1_2_3]

Checked that mate, with ignition on or off the blue/yellow wire has continuity to ground.is it just those two transistors that usually go, or is there any other thing?

[DonTZ125]

Those are the most common. Various capacitors - especially the cylindrical electrolytics - can also pop; look for a swelled appearance, or a distortion at the top. The resistors and diodes and other bits and pieces are fairly resistant to minor damage, meaning a failure is usually spectacular and obvious.

[hunter_1_2_3]

Well when I had it opened everything looked fine, iv seen ecus burnt out and damaged before and it's usually pretty obvious. But thats what's throwing me, is it common for both transistors to go without reason? and has anyone seen them go without showing physical damage(burn or scorch marks)?