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Hello all,

Came here looking for a hope and prayer. I'm at my witts end with this thing.

I have a everide warrior (model: ZKW2560) it has the Kawasaki 25hp (4H721V) v-twin engine on it.

Ran the mower great all spring and summer. then, when I put it up for the fall, I went out to start it just a couple weeks later to mulch up some leaves. It wouldn't start. I have tried so many things to get this thing running.

I got fuel (even tried spraying starting fluid in)
Got air
Tested for spark, Got spark
Got compression
I've bypassed the fuel solenoid
I've bypassed the kill wire on the coils
Ive checked the flywheel key, it was fine, I even replaced it anyways.

It just sits there and cranks cranks cranks cranks. Doesn't even try to ignite and fire. It has backfired a few times. Today I cranked the hell out of it for 10-15 mins and it started for about 3 seconds


I'm out of ideas.....

adjust the valve lash

bertsmobile1 said:

adjust the valve lash

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Excuse my ignorance, I'm not the highest mechanically inclined individual.

How do I go about doing that?

https://www.youtube.com/watch?v=4y7SCJ0pzP0
The process is similar to this.
You'll need to look up the lash specifications

Ignorance, is charging forward with no idea of what you are doing.
Intelleiece is asking for help when you need it.
You will find your manual here https://www.mymowerparts.com/pdf/Kawasaki-Service-and-Repair-Manuals/.
It is the 11 th line
Your engine is a FH 721V not a 4H

A couple of things you can do .

Remove the air filter and Check that the choke is fully closed


Get a can of carb cleaner spray ( it is easier on petrol engines than starter fluid )
Get some new plugs and warm them up in the oven ( helps to prevent them getting wet & shorting out )
Spray a tiny amount down each plug hole, pop the plugs back in and crank the engine.
Let us know what happens.

Do the same but this time spray the goo through the carb from a few inches away while cranking the engine
Let us know what happens

Check that the cboke

Iwill check this and update.

Sorry for the prolonged response. Holidays have been crazy. Hope everyone had good holidays.

So I checked the valve lash. It was good. I pulled the carb apart and it was spotless. Also I tried spraying starting fluid directly into the intake. Still nothing

As for the spec number, there was no tag on the engine cover. Is it stamped somewhere? because I couldn't find it

When you say got spark. Will the spark jump a 1/4" gap? Pulling out the plug and grounding the threads and watching for spark across the plug gap is not a good test. If the spark will jump a 1/4" gap in air it will run the engine. Always always always when trouble shooting a no start issue put a new spark plug(s) in.

Took them out and held them bout 1/4" away from a ground. Didn't arc. Both plugs.

It had to be pretty darn close to arc to ground.

I'm going to replace the plugs but I doubt they're bad. I just put them in. Where should I start after plugs? The coils?

Don't use the plugs to check spark. Remove the plugs from the coil wire and insert a bolt in the coil wire and hold that 1/4" from ground and crank it. If won't jump the gap sand any rust off the flywheel magnets and adj the air gap if still weak spark probably needs new coils but both bad at same time not likely.

Hammermechanicman said:

Don't use the plugs to check spark. Remove the plugs from the coil wire and insert a bolt in the coil wire and hold that 1/4" from ground and crank it. If won't jump the gap sand any rust off the flywheel magnets and adj the air gap if still weak spark probably needs new coils but both bad at same time not likely.

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I have found Kawasaki modules susceptible to cracking the epoxy in the modules and during periods of high humidity will cause the modules to short out. The ones that I normally see are due to a misfire, and when determining which side it is on will not start on either module if one plug is disconnected, but may start if both are connected,

Have come across a few Kohler and Briggs with the same issue, but seems to be a 10:1 ratio for Kawasaki to other brands.

I also have seen the steering diodes in the coils to be either shorted or leaky causing problems. To check for this disconnect both coils kill terminal.

AVB said:

I also have seen the steering diodes in the coils to be either shorted or leaky causing problems. To check for this disconnect both coils kill terminal.

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By disconnecting them do you mean just leave them unplugged or do I need to jump them to something?

Hammermechanicman said:

Don't use the plugs to check spark. Remove the plugs from the coil wire and insert a bolt in the coil wire and hold that 1/4" from ground and crank it. If won't jump the gap sand any rust off the flywheel magnets and adj the air gap if still weak spark probably needs new coils but both bad at same time not likely.

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Unless the rust on the magnets is deep enough to touch the coil laminations cleaning the magnets is a waste of time.
using harsh abrasives actually damages the magnets and should be avoided.
The rest of the information is worth acting on.

The kill wires ground the coils so they can not build up flux
So to test you just remove completely.
The chips react to voltages in the micro volt range .
The system was designed for single cylinder 2 stroke engines because points are very unreliable over 7000 cycles / min.
because the voltages are so low it was found with V twins the spark from one cylinder created a back current which interfeared with the second one so a diode was added while new Hall Effect trigger chips were being developed & tested.

bertsmobile1 said:

The kill wires ground the coils so they can not build up flux
So to test you just remove completely.
The chips react to voltages in the micro volt range .
The system was designed for single cylinder 2 stroke engines because points are very unreliable over 7000 cycles / min.
because the voltages are so low it was found with V twins the spark from one cylinder created a back current which interfeared with the second one so a diode was added while new Hall Effect trigger chips were being developed & tested.

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Disconnected them and I cranked the hell out of it. Holy mother of god. After about 5 mins of cranking it just backfired out the exhaust with a 3ft flame. I think I'm deaf now. I had the choke fully on so it must of filled with gas and finally fired.

But why wouldn't it keep running? The air box is completely off at this point so it's getting plenty of air.

Have you checked the flywheel key?

Scrubcadet10 said:

Have you checked the flywheel key?

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Yup, it was fine. Even replaced anyways

Fired on the wasted spark. I had one JD that did once in the shop. I nearly wet myself as I my 12 gauge or .357 was fired off right behind me.

Hmmm. When you bypassed the coils how did you do that? If you applied 12 volts to the kill terminals it would have destroyed them. If you just grounded that fine as that is the normal method of killing their output. Also when you bypassed the fuel solenoid on the carburetor, how did you do that one too?

Also have you tested the fuel itself? Fuel does go bad if it been around for a while. I have seen it where you couldn't get to burn when tested. Not going into how to this as it can be dangerous to do if done wrong.

Personally I have seen coils to fail sudden here in my shop after a especially severe lightning event but of I got a 2000' radio tower close by that draws the lightning so I have been stock in my a few times in the last 5 yrs because of the concrete floor. Just because you got spark outside the engine doesn't mean you have spark under compression; unless, it is able to jump at .166" or more. For a cold engine it also takes a stronger spark to arc the gap than it does once the engine is warm. A good example was Husqvarna ZTR that came running for deck work. I park it then a storm came that evening. The next morning I went to move to the repair area and it wouldn't hit a lick. A little tough to explain to that the coils overnight during that storm but he accepted it.

And a piece of advice don't be cranking the engine continuously for 5 minutes. It can overheat the starter and ruin it. The engine should normally fire up under 10 sec anyway ;though, a JD 737 I work on may take 20 secs sometimes.

AVB said:

Fired on the wasted spark. I had one JD that did once in the shop. I nearly wet myself as I my 12 gauge or .357 was fired off right behind me.

Hmmm. When you bypassed the coils how did you do that? If you applied 12 volts to the kill terminals it would have destroyed them. If you just grounded that fine as that is the normal method of killing their output. Also when you bypassed the fuel solenoid on the carburetor, how did you do that one too?

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I tried disconnecting them and starting them, not grounded to anything. I also grounded 1 to the negative battery terminal.

The fuel solenoid, it's just unplugged and removed completely from the carb. Might be why its backfiring.

The solenoid is help with the after fire noise on shut down. Shouldn't have anything to do with the noise during start up.

I removed it to eliminate the possibility of it stuck closed, not letting fuel come in. But that obviously isnt the problem since it wont even fire with starting fluid. I might as well put it back on.

Double check that timing key
It is easy to break them when tightening the flywheel bolt
I have done it more than once.
If there is the tiniest piece of debris or rust on either taper they do not lock together.
Lapping them in very fine grinding paste is a regular type job down here.
Also the taper must be dry.
If you put anything on it like grease, anti-sieze or even WD 40 it will not lock so the first time the engine cranks the key will shear.
Some times I have needed to resort to stuffing a cylinder with rope so I can get the bolt tight without shearing the key.
In these cases I use a paint pen to draw a line down the flywheel & across one coil arm with the cylinder at TDC so I know it did not shift when tightening the flywheel bolt.
I have also been caught out with debris in the bottom of the bolt hole so was just compressing the debris & not bearing down on the taper.

magneto coils are also handed so they have a right & wrong way to be fitted.

bertsmobile1 said:

Double check that timing key
It is easy to break them when tightening the flywheel bolt
I have done it more than once.
If there is the tiniest piece of debris or rust on either taper they do not lock together.
Lapping them in very fine grinding paste is a regular type job down here.
Also the taper must be dry.
If you put anything on it like grease, anti-sieze or even WD 40 it will not lock so the first time the engine cranks the key will shear.
Some times I have needed to resort to stuffing a cylinder with rope so I can get the bolt tight without shearing the key.
In these cases I use a paint pen to draw a line down the flywheel & across one coil arm with the cylinder at TDC so I know it did not shift when tightening the flywheel bolt.
I have also been caught out with debris in the bottom of the bolt hole so was just compressing the debris & not bearing down on the taper.

magneto coils are also handed so they have a right & wrong way to be fitted.

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Thank you, I will check this. I bought me a jaw puller so it's cake getting the flywheel off now.

They are best removed by placing a pry bar under the flywheel and prying up then with your other hand give the loose nut / bolt a strong "tap"
Pullers have a bad habit of warping flywheels.

Chughes2009 said:

I removed it to eliminate the possibility of it stuck closed, not letting fuel come in. But that obviously isnt the problem since it wont even fire with starting fluid. I might as well put it back on.

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At least you didn't cut the tip off like DYIers do, destroying a perfectly good solenoid.

Don't laugh folks either; new solenoids do fail to retract. I had three brand new Brigg's solenoid that fail to retract straight out of the package. My distributor refused to replace them say Briggs changed their policy and that I had to get a local delaer to warranty them. Well that doesn't work around here as all the I contacted refused to honor the warranty even with proof of purchase from the distributor because I didn't buy the part from them. So I am out over 150 usd for the parts.

The failure of the part was that it would not retract; unless, you bumped the pin. It was as if they 24 vdc versions instead of 12vdc. Anyways the customers mower and one my personal mower have been repaired with used solenoid recovered from blown engines.

And Chughes2009 Reinstalling it would be fine.

bertsmobile1 said:

They are best removed by placing a pry bar under the flywheel and prying up then with your other hand give the loose nut / bolt a strong "tap"
Pullers have a bad habit of warping flywheels.

Click to expand...

Personally I prefer using a harmonic balancer puller, tighten up. If flywheel is stubbornly stuck on the taper then using a brass 2 lb hammer smack the center forcing screw to shock the flywheel off, may need a few re-tightening of the center forcing screw. Anyways it is better than the possible crankcase or under the flywheel components damage. Some the newer engines have might thin crankcases and I have seen the pry bar method to break the crankcases.

I am in the bert camp on tbis one. I can get most flywheels off with the hammer method. I have a half dozen different pullers but the hammer gets most the work. Tappy tap tap.

i have not got around to pulling the flywheel yet but i was wondering. is there any safety interlocks that would keep it from firing? The parking brakes have to be engaged for it to turn over and the same goes for the PTO, it must be disengaged or it wont crank. anything else you could think of?

You said you have spark. But if you don't then it can be the seat switch [NO] or the seat switch relay but since it is cranking they are not play as both motion control arm are in park. Note this has 12 passing through it so they have more of tendency to go bad.

The following manual has the schematics.
Warrior OM and IPL

so i pulled the flywheel. i pulled the stator as well. the key was still intact and the stator showed no signs of damage, just a little dirty. i also put new plugs in it. i went ahead and took some emery cloth to both coils and the coil on the flywheel. still nothing. i did notice though, the tiniest chip was broken off the corner of one of the flywheel magnets. im talking less that 1/4'' though.

I am really stumped with this thing. I'm still leaning towards an ignition/spark problem. correct me if i'm wrong but even if it was extremely out of time or something else was wrong it would do SOMETHING with starting fluid being poured to it. instead it is doing NOTHING. NOTHING. the few times it has backfired im guessing it just filled up with so much fuel it either fired from compression/heat build up or the plug finally fired from being drowned in fuel.

im at the point now where im thinking of just replacing the entire ignition system starting from the stator down to the coils. but the odds of both coils failing at once is probably the same odds of hitting the lottery. i really dont know what else to do with it though.

is there any concrete way to test the coils or the stator?

i checked the wiring schematic but im not the greatest at reading them. would the voltage regulator being bad prevent it from firing? from what i gathered from the schematic, looks like it just controls the charge to the battery

The voltage regulator really has nothing to do with the ignition system if i read the service manual correctly.
Question: do the coils have a single tab for a single wire and not a multi wire connector? If so remove the wire from the coils. This eliminates something grounding out the coils. Set the coil to magnet gap the thickness of a piece of cardstock, about 15 thousands.
Stick a bolt in each of the plug connectors from the coils and position 1/4" from ground and crank the engine. If you get spark your ignition syatem works. It will run the engine. If you have spark the install clean dry spark plugs and connect. Now with throttle wide open and no choke spray about 1 second worth of starting fluid into the carb and try to start the engine. It should fire and run for a couple seconds. If it doesn't you either have a compression, valve seating or valve timing problem.
If you pull the kill wire off the coils and you don't get it to jump a 1/4" gap with the proper coil to magnet gap then you have a bad coil or weak magnet

The spark is generated by the magneto coils which are outside of the flywheel
The stator & internal magnets are just there to recharge the battery,
Kawasak actually give a cranking compression ratio which is 57 psi when the valve lash is smack in the middle of the specks.
SO measure it on both cylinders and tell us what you find.
Next measure the coil gaps using a pencil down the plug hole verify that the external magneto magnets have just started to pass the magneto coils when to piston is at TDC compression stroke ( inlet valve just closed ) and it should be the same for both sides
Also check that you are rotating the engine in the correct direction.

Now if you did not take a photo before you removed the carb, double check that the throttle & choke wires are hooked up correctly.
Being a V twin the throttle plate is set up so it can be used for either a left hand control or a right hand control.
Anr whike you are there verify that the throttle wire stretched the governor spring , causing the throttle to open fully.
Remember the throttle butterfly is the one nearest the engine and of course the choke works the choke and is closing when the cable is tight.

Also double check that the governor rod is holding the throttle butterfly wide open when the engine is not revolving .

Please do not feel embarrassed because we have all done it before and some more often than others/

Once the kill wires have come off the magneto coil there is nothing that can prevent a spark happening

And finally, toss a little of the fuel in a dish, soak it up with a rag the toss a match to it.
If it doesnt burst into flames then the fuel is off.
A lot of older fuel tank sealants cab be dissolved into the fuel rendering it non flammiable .
That last one took around 40 trips to a workshop to work it out.

Here's the info on testing the ignition coils. Personally I my $200 DVMM to do this but as noted some meters can actually damage the coil's electronics.

Also from personal experience yes both coils can fail on an engine. I had a Kohler v-twin last year that both failed on. Would not fire at all with both kill wires in place. Internally steering (blocking) diodes had failed. Though it is very rare that this can happen.

AVB said:

Also from personal experience yes both coils can fail on an engine. I had a Kohler v-twin last year that both failed on. Would not fire at all with both kill wires in place. Internally steering (blocking) diodes had failed. Though it is very rare that this can happen.

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I have seen it enough that most of the time I replace both at the same time. Nothing like having to pull an engine two hours after replacing a module just to have the other one fail.

The one time i have had a mower in the shop with both coils bad it was because one coil had failed sometime and the large V twin had enough power the homeowner didn't realize it was running on one cylinder. When the second coil died he brought it in. Could tell it had a dead cylinder for quite a while from the spark plug. You would be suprised how many V twins i see come in for annual maintenance that has a dead cylinder from a bad coil but customer thinks runs fine.

Here if a v-twin has a dead cylinder it usually shows as soon as heavy load is applied.

These mowers with 25hp engines on a 48" deck will do a pretty good job on one cylinder.

AVB said:

Here if a v-twin has a dead cylinder it usually shows as soon as heavy load is applied.

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You would be surprised how many people don't notice that they are running on one cylinder. Or even notice the power loss when it happens.

Got one in the workshop.
No right hand piston or rod.Customer claimed he bought it from new like that but the right hand bore is toast .
Sp most likely he saw it cheap ( cause the previous owner had butchered it ) convinced the treasurer that they needed & could afford the "new" mower and thus ended up with some "play money on the side .
Runs perfect but dies when trying to do a 6" cut

Are you that gullible? Just kidding. I had several customers to try to pull the wool over my eyes too over the years. I even had one that to identical mowers to try both fixed for price of one but he forget a couple important things. It was the serial number that I record on every repair that got him caught.

I once had a customer from the local Walmart try to claim that the oil leaked out of his new mower therefore leading to a broken rod. The problem was there was no evidence on the mower that the oil had leaked out. When I called him on it, he claimed that he washed all the oil off before delivery to me.

Well I can tell you this. I assured the gaps were right between the flywheel and coils, stuck a bolt in the lead, cranked it over, and it didn't go so well. At 1/4" it wouldn't arc at all, it had to be more like 1/8" or closer to arc. This was with the kill wire pulled off.

I've got 2 new coils on the way. I have not checked compression yet. Need to stop by the parts store and rent a tester still.

If the spark doesn't improve with the new coils what would be next?

Got 65psi on cylinder 1 and about 70psi on the other