kz750 ltd h2 1981 ignition coils connections pleas

[Click on image to enlarge view.]



Good Fortune!

Good Fortune!

Patton you ROCK with your excellent pictures and Info Posts! It would take me a week to do that.
So angel you do have a Multi meter for checking, as you already tested the coil ohm's. Just follow the picture and schematic above if your voltage is low, most likely is. If the fuse panel is new I would still start there, to confirm there is no voltage loss/ drop do to resistance. Resistance can most times be felt as heat, if you have warm wires near a connection, but several centimeters away they are cool or much cooler, you would have an issue with resistance from a dirty/ loose connection.
New coils may not perform any differently with out good Voltage reaching the coils.

Patton wrote:

Good Fortune!

I like the dangerous lightning storms !!! :woohoo:

But seriously, great work on making the graphics for people to see where they need to test!

dear kzr's

thank you everyone with this 'small orange spark' question.

how big should the spark be please? i can see the spark plugs spark.

many thanks

angel

Patton wrote:

Might be a red wire from harness (switched voltage) instead of a red/yellow wire.

With a good fully charged battery, and measuring near battery voltage being received at the coils, a blue spark visible at the plug tip in daylight is probably an adequate spark.

If weak spark persists despite ample voltage into coil, there may be a weak connection somewhere between coil and plug, such as coil>plug wire, plug wire>cap, cap>plug.
Or a defective cap (sometimes the resistors fail).
Or perhaps old hard worn out plug wires leaking voltage.
Or coil may be cracked, internally shorted, or otherwise failing.

Some coils have the plug wires permanently built into the coil, whereby it's difficult to replace just the plug wires without also replacing the coil.
Where needed, there's plug wire splicer available whereby the old wire may be severed near the coil leaving only a stub of old wire long enough to fit into the splicer, with the new plug wire running from the splicer to the plugs. See image below.

If coils are old and in doubtful condition, would consider relative costs involved, and replacing them, to avoid possibly wasting money on splicers.
Also get new Dyna solid core spark plug wires, which come with caps already installed
All available from Z1E.

Good Fortune!

Can't remember if ignition at hand is points, Kawasaki i.c. igniter, Dyna-S, or maybe something else, but thinking oem Kawsaki i.c. igniter ignition system.

Kawasaki i.c. igniter system sometimes uses a lower resistance coil than the typical 3 ohm (or higher) used with points ignition, or Dyna-S ignition which by-passes the i.c. igniter.
Some of the oem kawasaki i.c. igniter systems also use a separate resistor in the voltage feed to coil.

In any event, it's important to match the coil resistance to whatever is required by the particular ignition system.

Meanwhile, would presume that the existing coils are okay, until other possible reasons for weak spark have been ruled out.

Good Fortune!

Patton you should edit that last pic, and put a BIG RED X on that coil wire splicer! New wire or new coil with new wire.

Motor Head wrote:

Patton you should edit that last pic, and put a BIG RED X on that coil wire splicer! New wire or new coil with new wire.

:laugh: :laugh: :laugh:

I tried once, unsuccessfully, to implant a new "permanently installed" plug wire into an oem coil.

There's probably a way to do it, but I blew it.

The splicer is the only way I've seen to fit a new plug wire onto a good coil that has a bad (or too short) permanently implanted plug wire.

Good Fortune!

I'd toss it for a new coil, why splice to a defective coil wire? Even if you go the cheap EMGO route, its got to be better than the splice.

I hate to bump a thread so old but I was just working on my bike tonight (1982 KZ750H3) and this thread came in handy. I bought this bike non-running so tonight was the first time it ever fired on it's own, but it was only running on 1-2 cylinders, occasionally backfiring badly enough to blow smoke out the intake and stall the engine. After some cursory checks I had a theory that somebody had swapped 2 of the spark plug wires. This thread confirmed for me that plug wires #1 and #2 were swapped on my bike. It's too late now to start the bike without my neighbours making an angry appearance but since only pipes #3 and #4 were warm and it kept backfiring badly I'm pretty confident this was the issue.

Thanks to everybody that posted here, I think this thread just gave me the final piece of the puzzle to get my bike running!