**FIXED** 1981 Kz750E wont start after an accident

Patton wrote: Would remove spark plug, leave attached to cap, hold its base grounded against the engine, ignition switch ON, and spin over the engine--- does the plug spark? And if so, are sparks weak orange color or fat blue color?

If no spark, what is voltage being actually received ay the coil primary terminal when the ignition switch is ON?

Answers to these questions will aid in diagnosing the cause for failure of combustion.

The cause is usually related to either or some combination of:
Compression;
Spark (or spark timing);
Fuel mixture (gasoline supply and air/fuel ratio).

Good Fortune!

I checked the spark for each of the plugs and they seemed to be working. I think the sparks may have been that weak orange color, but I'll check again, thanks.

Another update. I forgot to mention that the bike just cranks really fast now but still wont start. Does that also point towards something?

[quote="Koki" post=533901...checked the spark for each of the plugs and they seemed to be working. I think the sparks may have been that weak orange color, but I'll check again...cranks really fast now but still wont start. Does that also point towards something?[/quote]

cranks really fast -- indicates battery is okay.

Weak spark could result from loss of voltage between the battery and the coil.
The voltage might be dropping at less than perfect connections of wires going into and out of the various connectors, fuse fittings, ignition switch, or the on-off switch, all of which are included in the circuitry between the battery and coils.
Voltage loss is often due to corrosion at a fitting, connector, or inside a switch, which may often be removed without needing any new parts.

Easy to test for loss of voltage between battery and coil.
With ignition switch ON, measure voltage between the battery posts.
Then measure the voltage being actually received at the coil primary terminals (usually via a red or a red/yellow wire connected to each of the coils' primary terminals.

If the voltage is significantly less at the coil primary than voltage measured between the battery posts, such condition indicates that voltage is being lost somewhere between the battery and the coils.

Inadequate voltage at the coils is one reason for a weak spark.

Good Fortune!

Update:
I sprayed starter fluid into the holes(cylinders) where the spark plugs sit and got a response from that. The engine fired and idled for about 3 seconds, then died(I couldn't rev my engine during the idle).

Have you ever cleaned the many and various electrical connectors & switches? If not, read this:

Cleaning Motorcycle Electrics

1. Get some of the De-Oxit electrical contact cleaner and figure on spending a good day going from the front of the bike to the back. It’s a plastic safe cleaner/preservative. www.deoxit.com is their website. It can be purchased at most Radio Shack Stores or any electronic supply places. Or use any plastic safe electrical contact cleaner(NOT WD-40 !).

2. On the older Kawasaki's, a majority of electrical connectors are inside the headlight housing requiring removal of the headlight, then the fun begins.

3. Do one set of electrical connectors at a time to avoid mixing up what connects to where. Usually disconnecting, spraying with De-Oxit and reconnecting is about all you'll need.

4. However, when encountering the green crud of corrosion, a brass wire brush may be needed on the pins you can reach. Some 400-600 grit wet and dry sandpaper strips rolled into a tube should reach the male and female pins in the more difficult to clean connectors.

5. Smoker’s pipe cleaners, cotton swabs and wooden toothpicks work as cleaning aids.

6. Really small electrical connectors may require the use of a welders tip cleaning tool assortment.

7. Most pins in the connectors are coated with a thin plating of tin, and others may be nothing more than copper or brass.

8. If moisture is added, the resulting corrosion lowers the voltage/current being carried causing dim lights, slow engine cranking, slow turn signal responce and lower input voltage to the ignition coils resulting in weak spark.

9. The left and right handlebar switch pods will need attention too as they have circuit functions like turn, horn, run/stop, and start. The older Kawasaki’s have reports of the soldered connections crumbling, if your bike has this problem, just ask, as I’ve got a repair procedure for this.

10. Usually a spritz or two with actuation of the switch is about all needed for these switches unless corrosion is detected and then careful disassembly is required.

11. The ignition switch may or may be not sealed to allow spraying the internal contacts. I urge caution if attempting to open this up as springs, and ball bearings may fly out never to be seen again!

12. If your bike has the older style glass tubed fuses, I suggest replacing them as vibration can cause internal failure. AGX is the type used, and most auto parts stores can get them for you, along with boating supply stores.

13. Clean the fuse holder clips, looking for signs of overheating(discolored insulation, signs of melting). I use metal polish on a cotton swab, followed by spraying another clean swab with the De-Oxit and then rubbing the inside of the fuse clip.

14. All battery cables must be clean and tight for maximum current transfer. Check the cables going from the Negative(-) battery terminal/post to the engine mounting bolt

15. Also the one going from the Positive(+) terminal to the starter solenoid and from there to the starter motor.

16. If any battery cable feels ”Crunchy” when flexed, replace it as possible corrosion is inside the insulation. Inspect all heavy duty battery cables and the smaller wire terminations(Bullet Connectors), for failed crimps, and those used in the electrical connectors, as they can fail over time.

17. Each "Bullet Connector" will have to be sprayed to ensure good connectivity, especially the ones going to the energizing coil of the starter solenoid.

18. The alternator output “Bullet Connectors” are usually behind the engine sprocket cover and will need inspecting and cleaning too.

20. The turn signal light sockets will benefit from a spritz from the contact cleaner along with the tail light/brake light socket.

21. Some brake light switches can be sprayed on the actuating rod, with the spray running down inside to the electrical contacts, others may be sealed requiring replacement if the switch is intermittent in operation.

22. Some people put the Di-Electric Grease on cleaned terminations/connectors, I don’t, as I’ve read/heard it can cause problems when it gets hot, actually insulating the connections, so the choice is yours to use or not.

I think I've covered about all of the electrical systems on the bike.........

“I spent a weekend going through every electrical connection and switch on the bike with a little scotchbrite pad and DeOxit - what a difference! Everything was brighter, gauge backlights, indicator lights, turn signals, I was getting a nicer spark, it fired up quicker, etc. Well worth my time. WELL worth it! “

From a forum member at www.kzrider.com

And if while cleaning the handlebar switches, you discover failed or failing solder joints, do this:

Read this for a primer on hand soldering: technologyinterface.nmsu.edu/fall97/electronics/solder.html

Repairing Motorcycle Soldered Connections on the older bikes.

When repairing soldered wires on motorcycle switches or light bulbs sockets, have the following on hand:

1. A 25 Watt soldering iron or one that the wattage can be adjusted.

2. Rosin core solder of 60/40 type. SN60 or SN63 is preferred.

3. Rosin flux or soldering paste (Never use solder or soldering paste designed for plumbing work, as it contains an acid that will corrode the electrical joint, ruining it).

4. 91% rubbing Alcohol, or 70%. The lower percentage will clean up flux residue, but not as good as the higher percentage stuff. Acetone does a good job of removing excess solder flux too.

5. A cut down ½” paint brush, or acid brush for scrubbing the repaired solder joint.

6. Clean rags or paper towels

7. A damp sponge to keep the soldering iron tip clean.

8. Some “Solder Wick” a braided bare copper wire designed to collect heated excess solder, aiding in joint preperation, available at electronic supply stores.

9. Some wooden toothpicks.

10. Small Hemostats or clip on heatsinks.

A. Before soldering, “Tin” the soldering iron tip by plugging it in or turning the iron on, allowing it to get to operating temperature(2-3 minutes).

B. Unroll about 3” of solder from the roll of rosin core solder & then using a clean rag or paper towel moistened with Alcohol, wipe the unrolled solder, removing the finger print oils that will create a poor solder joint.

C. Apply a small amount of solder to the now heated soldering iron tip, wiping the excess off with the wet sponge, keeping a thin layer on the soldering iron.

D. The soldering iron is now ready for use, but before applying the heated tip to a wire, wipe the tip on the damp sponge, this removes any oxidized solder and makes for a much better connection.

E. If the joint to be repaired is grey in color or appears “Crumbled”, apply some rosin soldering paste or flux to the joint with a small toothpick or screwdriver, and then apply the soldering iron tip for a few seconds.

G. The fluxed joint should clean up, allowing for a better connection. If no luck, use the solder wick to remove all traces of the old solder by apply in it between the soldering iron tip and the bad joint.

H. Hemostats and clip on heatsinks will be used to prevent the wire insulation from burning, overheating & pulling away from the connection.

I. Apply a small amount of flux to the joint to be repaired & then a very short duration of heated soldering iron tip & solder(like a few seconds or so).

J. Clean off the repaired joint with the brush & rubbing Alcohol or Acetone, the newly repaired joint should appear clean and bright, almost as if it were polished, with no voids or holes.

K. When repairing the bad or "Cold Solder Joints" (as the Electronics industry calls them), it takes really no special skills, just patience, and a place to work(along with the mentioned tools. You've got to be sober, and not stoned, as the soldering tool can be at 700 F, possibly giving the impaired bike owner severe burns.

L. If you have fine muscle control problems, have a friend do the soldering for you. Moving a wire before the electrical joint has properly set up, can create "Cold Joints" too. If possible, practice on the bench top with some scrap wires before attempting repairs on the bike.

M. This information comes from years of missile test cable and equipment assembly, when I worked at General Dynamics/Convair Division in San Diego California, on the BGM-109 Tomahawk and later on the AGM-129 Advanced Cruise Missile. This was from 1983-1993. The company had a week long soldering school, where you learned to solder meeting “Mil-Spec” standards.

Koki wrote: Update:
I sprayed starter fluid into the holes(cylinders) where the spark plugs sit and got a response from that. The engine fired and idled for about 3 seconds, then died(I couldn't rev my engine during the idle).

This indicates a failure (for whatever reason) of fuel mixture reaching the combustion chamber.
The step-by-step method --
Is there sufficient gasoline in the fuel tank?
Does gasoline flow through the petcock when set in PRI position?
Is gasoline flowing through the fuel line and through the in-line filter?
Is gasoline flowing through the float valves into the carb float bowls?

With gasoline in the fuel tank, and the petcock set in PRI position, and choke ON, and not touching the throttle grip, ignition switch ON, On-off switch in RUN position, try again to start the engine.

Good Fortune!

Patton wrote:

Koki wrote: Update:
I sprayed starter fluid into the holes(cylinders) where the spark plugs sit and got a response from that. The engine fired and idled for about 3 seconds, then died(I couldn't rev my engine during the idle).

This indicates a failure (for whatever reason) of fuel mixture reaching the combustion chamber.
The step-by-step method --
Is there sufficient gasoline in the fuel tank?
Does gasoline flow through the petcock when set in PRI position?
Is gasoline flowing through the fuel line and through the in-line filter?
Is gasoline flowing through the float valves into the carb float bowls?

With gasoline in the fuel tank, and the petcock set in PRI position, and choke ON, and not touching the throttle grip, ignition switch ON, On-off switch in RUN position, try again to start the engine.
Good Fortune!

Patton's right here, I'll add to check the fuel down to the bowls by opening the drain screws, this should make fuel come out the drain tubes, with petcock on "Prime"

Koki wrote: Update:
I sprayed starter fluid into the holes(cylinders) where the spark plugs sit and got a response from that. The engine fired and idled for about 3 seconds, then died(I couldn't rev my engine during the idle).

Soundls like a fuel problem or a vacuum leak. The side flip might have stirred up tank sediment and clogged the petcock/jets etc. I'd flush the tank with mineral spirits, clean the petcock. Install or change inline filters, flush the carbs downward (open the drains and pour solvent through). Might soak with Seafoam and rebuild if they still won't run.

Yeah I started cleaning out my carbs yesterday. I found that one of them was pretty gunked up and had some green stuff around the jets, but I did my best to clean it up. Hopefully this'll be the last things I have to take apart...

Hopefully this'll be the last things I have to take apart...
:laugh: :laugh: :laugh: :laugh:
I needed a good laugh tonight.

Well, turns out one of my carb inlet rubbers was melted and cooked hard.
Anyone know where I could look to try and find another one?

Order 4 from www.z1enterprises.com