Engine, electrical trouble

[WH252-H 4]

Hello,

I'm a newbe to Wheel Horse. Recently, I was given a 1988, 252-H (22-13KE01). This has the Kawasaki FB460V-AS26 engine. It had not been started in about 2 years. I have gone completely through the tractor and it seems to be in good condition. I was able to get this running a week ago and it ran quite well for several hours. I do this with machines that have not ran for awhile. I change oil & all filters and use high octane fuel with Lucas fuel treatment. I start them and let it run for a long time, checking often for any problems. This ran for about 2 hours with no problems. I had started it since several times to move it around, no problems!

Now I'm having issues! No spark or weak spark. The coil checks within specs for primary and secondary. The igniter only has 1.3 ohms of resistance. If I understand the specs this could be the problem. I have one ordered! The part that confuses me is I had all the same readings before I had it running for hours. I get blue spark from the bare spark plug lead to head bolt. sometimes, blue spark at spark plug with the boot on but install plug and no ignition. sometimes no spark or weak spark and sometimes no spark until I barely lift it off the head bolt while turning over, then I get a very weak spark.

Scratchin my head, Bob

[tunahead72 2,347]

:WRS:

Did you replace the spark plug?

[WH252-H 4]

Yes, I tried two plugs. Same result.

More to the story: When I got the tractor it had a bad coil and the PO had put the wrong ignition on it. Somehow when the key was in the run position it would send juice to the coil. I did not know this so I replaced the coil ($56), turned the key to run before starting it and here this crakling sound. I still had the fan shroud off so I could quickly see the side of the coil expanding. Luckily I caught it in time. I was able to download an awesome electric book for WH/Toro and discovered the ignition issue. Unfortunately, when the key was in the run position 12 volts was going thru the igniter to the coil continuously. I unhooked the wire to the igniter and thats when it was running well but to kill the engine you had to ground out the igniter wire.

Now I have the correct ignition, everything is connected properly (triple checked), the coil tests within spec but the igniter does not. So this is why I believe its the igniter.

This is my first experience with Kawasaki engines so I need the help!

[Save Old Iron 1,563]

So this is why I believe its the igniter.

Bob,

If the "igniter" is a small controller box on an early version electronic ignition system, I can probably take you at least one step further in the diagnosis. An engine wiring diagram would be helpful, The igniter acts as an on and off switch to pulse the primary of the ignition coil - an electronic version of the mechanical points in a Kohler K series engine. That function can be imitated by a jumper wire to confirm the condition of the coil / igniter setup. The 1.3 ohms you mentioned in the above post would indicate the output transistor inside the igniter is shorted (always a low resistance). Try swapping the black and red ohm meter leads and see if the ohms value goes to over range. If not - and stays around 1.3 ohms - I would say the igniter is toast.

I have never worked with a Kawasaki LG ignition. Does the ignitor box open up to allow isnpection of the internal circuitry ?? Any burn marks visible ??

If the "igniter resistance" you speak of is in the ignition switch, here are a few diagrams to help with the diagnosis. Resistance between the connected terminals, in any position (off, run, start), should be virtually zero ohms.

If you have a digital ohm meter, note the resistance displayed on the meter with the meter leads shorted together. Subtract this "residual" reading from any reading you make on the ignition switch terminals. If you have an analoge meter, zero out the pointer with the meter leads shorted. And of course use the lowest ohms scale on any meter when measuring continuity.

[WH252-H 4]

Thank you SOI

The term "Igniter" comes from Kawasaki. Not sure what it is but it's a little larger than a quarter and it screws to the head next to the coil. A wire from the "M" terminal of the ignition eventually splits and goes to the primary terminal on the coil and the "Igniter". The engine was running without the igniter connected (per advise, to determine where original problem was) but the engine will not shut off with the key. You have to ground the igniter wire to kill the engine. I then discovered the ignition was not the correct ignition.

You believe the coil is bad even though I get ohm readings within spec's? Your explanation makes sense.

I read and two people explained how important it was to make sure the igniter had good clean contact to the head so it would be grounded properly, that was followed by, "the engine will run without the igniter". It doesn't seem all that important if the engine runs without it.

The new igniter should be here today. I will install it and it that does not solve the problem, I'll have to cough up another $56 for the coil. Painful very painful!

Thanks

[WH252-H 4]

_{Save Old Iron,}

_{I must apologize! I read your post befor going to bed last night. I did not reread it this morning before I replied. You explained what the igniter does. Thank you!}

_{The ohms are 1.3 with meter leads swaped and the igniter removed. The ohms increased slightly when testing it installed with wires attached.}

_{There are no burn marks and no way to open it.}

_{Just as a side note, I see you have the drawing of the correct ignition 103991 (6 lug). The previous owner installed a 103990 (5 lug). Didn't quite work out!}

[Save Old Iron 1,563]

The engine was running without the igniter connected

That makes sense if by "running without it connected" you mean the "kill" wire to the igniter was removed from the "M" terminal of the ignition switch. When the "M" terminal is grounded, the drive signal to the igniter is removed and the ability of the igniter to "fire" into the primary of the ignition coil is removed. If the specs are good on the ignition coil, I would go with the coil being OK. At this point, I think we fried the ignitor by applying 12 volts (from the old ignition switch arrangement) to the tab on the igniter that should only be open or grounded by the correct style ignition switch.

This syndrome happens quite often when folks put the wrong ignition switch in a magneto based tractor. The primary of the magneto is a very low ohms, very thin wire wound coil that fries quickly when 12 volts is applied. The primary wires of the magneto are wound to convert the magnetic field of the flywheel magnet into an electrical pulse to fire the secondary of the coil. The kill wire going to "M" terminal serves to divert the weak electrical charge created by the flywheel magnet directly back to ground. The only thing going thru a mags primary wiring should be the magnetic field current induced from the flywheel - NEVER BATTERY POWER.

I'll have to create a post on what happens when battery power goes thru a magneto - this happens way too often and I don't believe folks truly understand why the mags fry under these circumstances. Not knowing gets very expensive very quickly !!

Maybe I can find a wiring diagram for a KAWASAKI setup later today. We have not even touched on the safety interlock influence in this whole effort. I would really need to see wiring diagram to make recommendations on how to troubleshoot the safety locks out of the equation.

I love the smell of igniters in the morning - it smells like - LEARNING.

Learning SOI style.

[WH252-H 4]

I have the diagrams but there in a 30mb file and covers toro/wheel horse from 1985-2001. Its the "Toro Consumer Products, 1985 - 2001 Riding Products Demystification Guide, Electrical Circuits Troubleshooting Guide". Quite a title! I'll look for a link.

Bad news! New igniter is on with correct ohms readings but very week to no spark! I'm thinking, you were correct about that coil.

[WH252-H 4]

this link should work

https://homeownersol...nualsResultPage

This should take you to the correct page select manuals then open the guide or download it.

[tunahead72 2,347]

The Demystification Guide is also here on RedSquare, under the Files tab -- still a very large file, but easier to get to:

Your 1988 252-H starts on page 5-51 of that document, Adobe Reader page 181.

[WH252-H 4]

Thanks Tunahead

SOI

I noticed a pattern the last several times I've tried to start it. It will spark at first but then die off quickly. If I wait overnight I might see several blue sparks then orange and then after a few minutes, no spark. Is this the symtom of a fried coil?

I have a new coil on it's way. I found a "Kawasaki" Coil for $45. A little relief!

[ericj 1,576]

is the battery weak this could cause the loss of spark as the battery goes down, just a thought !!!

eric

[Save Old Iron 1,563]

SOI

I noticed a pattern the last several times I've tried to start it. It will spark at first but then die off quickly. If I wait overnight I might see several blue sparks then orange and then after a few minutes, no spark. Is this the symtom of a fried coil?

I have a new coil on it's way. I found a "Kawasaki" Coil for $45. A little relief!

That seems to be the failure mode for smoked coils - Kawasaki or otherwise.

A general rule with anything electronic is once you let out the magic smoke or magic cracklin" sound in the device - its gone!

These coils are nothing more than a big "coil" of bare copper wires insulated only by a film of varnish for insulation on each strand. Once you melt the varnish, vibration of the engine and expansion caused by natural heat produced during operation causes the coil wiring to expand, rubbing bare wires against each other and shorting out parts of the coil. It doesn't take a lot of change in resistive value to screw up a coil. Think of a coil as the equivalent of a metal musical bell. A small crack in the bell can cause it to thud instead of ring when hit by a hammer - same idea electrically for a coil. A good hot spark is actually a long series of little sparks caused by electrical "ringing" of the coil. Screw up the coil and you get the electrical equilivent of a "thud" - a weak spark.

P.S. I still have no clue why they use an igniter - to pulse the primary or just act as fancy kill device for the coil. One day we will find out and my journey into the Karma of Kawasaki Kombustion will be Komplete.