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Kawasaki FB460V 12.5 hp Won't Start Weak Spark

bertd
10 years ago

Hello. I tried to post earlier and it didn't appear. Anyway, I have a Kawasaki FB460V FS08 12.5hp single with weak spark. I have to pull it about 75 times to start when cold. It usually floods before it finally starts. New float needle and carb cleaned. Runs good when running, and restarts when warm. Looks like spark is weak. New plug did not help. Any advice on the coil and igniter on these engines. I looked at manual and do not understand how to test them. Any tips? Is Mownie still around? He and Tomplum helped me tremendously a couple of years ago. Thanks.

This post was edited by bertd on Tue, Nov 19, 13 at 16:22

Comments (30)

  • tomplum
    10 years ago

    How have you verified spark and the flooding condition? There are tests in your manual for both the coil and igniter- correct? Do you have a reliable ohmmeter to do the test- or does something just not jibe upstairs? I can say that I fall in the category of taking an igniter out of stock and slapping it on and if it runs, then great and if not it comes off. For free, you can slit the rubber seal on the spark plug connector and be certain that the wire is securely screwed into the connector on both ends.Coil gap can be verified and you could clean up the ground at the igniter screw. Also verify that whatever shuts this engine off is not partially grounding the coil.

    Here is a link that might be useful: Kaw manuals

  • bertd
    Original Author
    10 years ago

    Thanks Tomplum. Sorry I didn't respond sooner, but was called away. Carb gets fuel. When I pull and pull, eventually you can see puddle of gas in the ventura or carb body where the air filter mounts. It has a key switch to turn off, but it's a pull start. Plug sparks when placed against head, but seems to be pinkish. Different plug, same result. I tested spark with one of those OEM brand manual coil testers with the adjustable gap thing, and it would not arc unless air gap was very small. I know I used the same method on a Briggs L engine before and it would arc at 10 and higher. Not sure if this Kaw engine should do the same, but it will only arc around 2 or so. Anyway, the problem is "upstairs". I have an ohm meter, but not enough sense to use it. I think I understand how to test the coil according to the manual, but instructions on testing the igniter are not clear to me. I'm not sure where to put the test leads. Have you tested an igniter this way? Any tips on where to put meter test leads on coil and igniter would be a big help! Thanks.

  • mownie
    10 years ago

    Bert, depending on which type igniter is featured on your engine (AS or BS) determines where you put the ohmmeter test leads.
    If it is type AS, the 2 wire leads of the igniter are where you touch the ohmmeter leads.
    If it is type BS, you place one ohmmeter lead on the metal case of the igniter and the other ohmmeter lead on the wire terminal marked A in the Kaw manual illustration.
    When you are testing circuits with an ohmmeter, do not use your bare hands to hold the ohmmeter test leads onto the conductors you are testing. Holding them in place with bare hands can affect the accuracy of the reading because the human body is also a conductor. Holding test leads and/or the conductors being tested with bare hands puts the body between the 2 hands into the circuit and can skew the results.
    Best to use alligator style clips or lay the component on an insulating surface so you can press the ohmmeter leads to the test site without your hands touching anything about the parts being tested.

  • bertd
    Original Author
    10 years ago

    Thanks Mownie. Here is what I found. On the COIL, Primary should be between 0.4 - 0.8. Mine is 0.9. However, on the secondary (plug lead to core) I found something unusual. The manual specs say 10 to 18k range. When I set my meter on 20k, 200k, 2000 or 20, it reads 1.0. But, if I set my meter on 2000k, then it reads about 1250. Is this normal?
    On the IGNITER, (it's the B type) I dont';t understand the two specs in the manual, but they should be either 4.0-3.0k. or 10 to 40 depending on which heading you look at on the chart. With the tester to the terminal A and the case, like you advised, here is what I get. With meter set on 20k, I'm reading 1.39. With meter set on 200k, I'm getting 1.3. With meter set on 2000, I'm getting 927, and with meter set on 200, I'm getting 1.0. However, a footnote in the manual says "resistance value may vary with individual meters". Make any sense to you?
    If I need parts, any suggestions on best prices online. Not sure if you can promote on this website, but let me know if it's ok. Thanks again for your help. Bert.

    This post was edited by bertd on Wed, Nov 20, 13 at 17:04

  • mownie
    10 years ago

    ***"on the secondary (plug lead to core)--manual specs say 10 to 18k range--When I set my meter on 20k, 200k, 2000 or 20, it reads 1.0. But, if I set my meter on 2000k, then it reads about 1250. Is this normal?"***
    If you are getting that low a resistance value, the secondary windings would be shorted somewhere internally.
    ***" either 4.0-3.0k. or 10 to 40 depending on which heading you look at"***
    My take on the 2 seemingly different values is that type AS has a separate ground lead to provide the negative circuit path AND the internal works are INSULATED from the metal case. The 10 to 40 Ohm value there would mean that there are no shorts to the metal case from any circuits common to wire A on that style.
    The 4 to 3 Ohm value would apply to both styles when testing from terminal A or wire A to terminal B or to the case.
    So, if you are getting accurate Ohm readings, it seems that the igniter may be shorted too.
    Perhaps you might want to hand carry the coil and the igniter to a qualified small engine shop and have them test the coil and igniter to see if their results match yours.
    I only know of 1 shop that is a Kaw service center near you.
    Chilton Turf Center on Wedgewood Ave, Nashville

  • bertd
    Original Author
    10 years ago

    Thanks Mownie. Yea, the coil secondary readings jumped out at me as odd. The trigger (igniter) values were strange too. I checked both over and over and continued to get pretty much the same readings each time. I am familiar with Chilton. I'm about 15 min away. There's another Kaw/mower shop in Green Hills that I would not do business with unless last resort. Attitude problems. Also one in Brentwood I'm not familiar with.
    I found one "new" OEM coil on ebay for about half price yesterday and went ahead and ordered it. It is returnable, so we will see if it is what he says it is. Seller is a private individual and had excellent feedback ratings.
    On the trigger, The OEM's are pricey. There are some aftermarkets triggers on ebay under $15 that cross reference to my part number. However, the BS, single prong, like mine, appear to be a little longer and the terminal tab is on the bottom-left instead of the bottom-right. Any experience or feedback regarding these aftermarkets? The trigger OEM part number was 21119-2095, superceded by 21119-2161. If you check major parts warehouses on the web, many show this # in photos as the AS type and some show it as the BS type. Confusing! I'll call Chilton and see if they would test it. Otherwise, would you try one of the aftermarket triggers I referred to before dropping $60 on an OEM? Thanks again. Get ready for that winter blast this weekend and stay warm!

  • mownie
    10 years ago

    I would be skeptical of trying something that looks like a "mirror image" without knowing if there is a reason for the change. While it might be just that the photo got flipped, it might also be a cheap copy of the real McCoy.
    I have not had to buy any Kaw parts other than carb kits, so I can't speak about whether the "different" terminal location might simply be an upgraded version of the genuine Kaw igniter.
    The guys at Chilton ought to be able to shed some light on this.
    Too bad Brookside Mower Repair no longer exists (so far as I know). They were located at White Bridge Road and Charlotte and would be about 2 minutes from you. Their parts counter would be square in the middle of the right turn lane of westbound WB Road today :^)

  • tomplum
    10 years ago

    Glad to see you are getting to the bottom of this. I've seen the little aftermarket modules, probably have one somewhere- but always bought the igniter direct from Deere in what I work on. An FYI, they used to say that the replacement igniters were the same between between say a rider (electric start) and walk behind (pull start). Somewhere about 5 years ago they had a timing change and made a different one for the walk behind. Let us know how it works out. Mownie to the rescue as always! As an afterthought, you can try to narrow the coil gap slightly to .008 to see if your spark quality improves.

    This post was edited by tomplum on Thu, Nov 21, 13 at 10:30

  • bertd
    Original Author
    10 years ago

    Thanks guys. You are correct Mownie. Brookside was awesome. I did business there years ago. I'm about 5 min. from that intersection. White Bridge Rd. used to be two lanes, now five! I contacted someone at Chilton, and it seemed to be more of a hassle to go that route for various reasons. Tom, sorry I didn't describe my mower better. It's about a 1997-98 Toro with a 52" deck that I bought new. I have a sulky (which is no longer made), so I consider it a rider. Anyway, I went ahead and ordered the aftermarket trigger this morning for two reasons. First, it was $15 vs $60 for an OEM. Second, I read all negative feedback for various sellers on ebay selling this specific aftermarket part and no complaints found. Apparently, it has worked for hundreds of people, so I'll give it a shot. How long it will last, may be a different story. I should have the new coil and trigger by Monday or Tuesday of next week, so I'll post the results for everyone to see once installed. I think I'll install the coil first and test the mower since it's harder to install/remove. If that fixes it, then I'll have an extra trigger for future testing. If not, I'll then install the trigger and see what happens. I'm also going to check resistance on both new parts and compare to the readings on my current parts. May help someone else in the future. Again, thanks to both of you and I'll update asap. Bert.

  • bertd
    Original Author
    10 years ago

    Finally got to work on the mower today. At my wit's end! I received the new coil and trigger. The new coil was in spec according to my meter. The old coil was not. I thought for sure this would be the problem. Installed the coil and left a .3mm or .012" air gap as the manual instructed. Mower would not start, but it was getting spark. I then installed the new aftermarket trigger. Again, would not start, but it had spark. After about 80 pulls and cleaning the new spark plug about 30 times, it started. I'm back to square one.
    Here are the symptoms: If I try to start it on choke, no luck at first. It won't hit a lick! If I move the throttle to slow speed or above, the intake gets visible gas in the bottom after a few pulls and the plug gets wet. After 70-80 pulls, and constantly cleaning gas off of the plug, and wiping gas out of the intake, it started on choke. When throttle is set on slow or more when trying to start, it floods quickly and is very hard to pull the starter. Once warmed up, it will restart pretty easy. It will just not start cold unless I do the above. I broke my humerus in half two years ago in a fall, and don't need to be pulling this beast that many times!
    A footnote: I played with the mixture screw some as I tried to start it. Factory static is 1 1/8 out. This didn't seem to have much affect, except on one occasion. I turned it in, which I believe leans the carb on this model, and the intake filled with about 1/4 inch of gas. Not sure if it had just built up or where it came from so fast, but it was a bunch. It never did that again.
    As mentioned, I replaced the float needle a couple of weeks ago. Tested the float submerged in a jar of gas and no holes. Float level is level when upside down. Carb has been cleaned several times. Gas is fresh. Not sure where to go from here? Mownie and/or Tomplum, please rescue me! Thanks.

  • bertd
    Original Author
    10 years ago

    One more thing. Any chance these symptoms sound like the pilot screw tip may be bad? I removed and cleaned the pilot jet. The screw looked ok best I recall. I've never turn it hard when bottoming to adjust.

  • tomplum
    10 years ago

    Thinking this through. It runs well once started and will restart warm. It has enough compression to draw fuel up into the chamber, but the fuel won't ignite. Has a new spark plug, but the correct plug? The aftermarket igniter is a bit of a wild card. Maybe that could be the culprit. I think I mentioned on Deere Kaws anyway, they came to delineate between the recoil and electric start models. At least that is what I read into it. If the ignition timing is not quite right, it will be less forgiving cold. Maybe try an .008
    " coil gap for giggles. Flywheel key not partially sheared? Valve gap been checked?
    Does this engine use any oil or is it high hours? Thinking maybe a carboned up combustion chamber. Reaching here. May eventually worth a look at the valve seats and do a clean up.

  • bertd
    Original Author
    10 years ago

    Thanks Tomplum. Engine does not have high hours. Igniter I think works the same as the original. Uses NO oil. I had to change the lower pan gasket last year due to a leak and everything inside looked very clean from what I could see. Timing was set properly (the second time). I have no experience with a "partially sheared flywheel key". No experience with valve gap either. Motor has been sweet for many years and just started this crap last year. Hate to tear it down if it's a carb issue or something simple. Would a compression test in the plug hole tell us more? Thanks, Bert.

  • tomplum
    10 years ago

    "Would a compression test in the plug hole tell us more?" Possibly. Double check your manual on the spec,Section 6. They also say that if you were to back spin the flywheel and it kicks back- you have allowable compression. That of course is dependent on the drag on the engine from the belts below. You could perform the test cold vs hot and even try it w/ a tablespoon of oil in the cylinder to see if there is an appreciable change in the reading. Valve clearance specs should be later in the chapter. To check them on your engine, you have to remove the rectangular cover on the block behind the carb area. In regards to the spark plug, if you haven't already- try a J19LM if you have room in your application rather than the CJ Bantam plug. As stated before, a partially sheared flywheel key will affect your ignition timing, As your key is likely a woodruff style key, you must pull the flywheel to check it. Keep us in the loop!

  • bertd
    Original Author
    10 years ago

    Thanks Tomplum. It will not start again this a.m. I put the old trigger back on and same result. It ran good last night with the aftermarket trigger (once it finally started)! I tried to test compression and my guage is very old and doesn't really start to register until about 50psi. I'm not getting a reading. On my way now to buy a new one. I'll let you know in a couple of hours what the reading is. Once before I replaced the bottom pan gasket and got the timing off one tooth. It would not start at all and reminds me of the way this thing is acting now. If compression is withing spec, do you think I should I go directly to the flywheel key for inspection? Still getting spark and gas, but not starting. Thanks again.

  • bertd
    Original Author
    10 years ago

    Checked compression cold. Most I got was 30psi. Manual says not below 50 in one section and not below 43 psi in another. Pulling valve side cover and head now. Not sure what I'm doing, so any tips on what to look for would make for good reading tonight. Thanks.

  • tomplum
    10 years ago

    Good call. Did you perchance repeat the test w/ oil? A look at the valve seats and the underside of the contact area of the valve should ideally not be pitted / show signs of not seating. Blackened gasket sealing areas or deteriorated gasket itself can be signs of where some of the compression loss could be. Should you clean the deposits out in the head, be mindful not to scratch the aluminum. The valves should be have a gap of at least .004" - more details in the manual.

  • bertd
    Original Author
    10 years ago

    Latest update! I forgot to check the darn compression with oil. Too much on my mind. Combustion area in head is pretty clean. Cylinder bore looks very clean and smooth. Top of piston is pretty black, but no caked-on deposits. Can't really see the valve surfaces well, but they don't look as smooth as the seats.
    Also, I measured the tappet clearance between the valve stem and tappet at TDC on compression stroke. According to the manual, both valves should be between 0.1mm - 0.16mm. My exhaust will fit a 0.08mm feeler guage and below. It will not accept a 0.1 or larger. My intake will not quite accept a 0.05mm feeler, much less anything larger. That's as small as my guage goes.

    Is this enough variance to cause my problem?

    Not sure if I'm qualified to grind the stems as the manual shows. I don't have a spring compressor or a lapping guide. Any suggestions? Thanks

  • bertd
    Original Author
    10 years ago

    I forgot to mention that the head gasket looked fine. No signs of leaks. If you think I should grind stems for proper tappet clearance, I thought I would lap the valves/seats while they were out. I saw a video of a guy do this on a Briggs using the suction cup/wooden pole method. He started with 120 grit compound and finished with 240. Then I read others say don't lap valves at all. What are your thoughts lapping and on on the wooden stick method? Also, I can get a model #19063 spring compressor for about $25. Is this the best way to go? Thanks.

  • tomplum
    10 years ago

    The little Lisle 23300 compressor is a bit cheaper. It sounds like you need to pull the valves from your description. It the valves are pitted, replace them or have them ground if it is economical.If the seats have imperfections, best take it to shop who can cut the seat. Lapping valves is a good thing to do when you are dealing with surfaces that need just a little help mating. If both surfaces don't seem so bad- go for it. It would go without saying that the compounds need to be cleaned out well when you are done. When pulling the valves, ensure that they work back and forth freely. Replace the valve seal and gaskets. Setting the gap is easy, just don't over do it! As long as you have clearance, lap them in. For final clearance, use the side of a fine grinding wheel to remove small amounts of stock from the stem at a time. Twist the valve as it contacts the wheel while holding it steady. Test the valve clearance as you go until it is in spec. If you are friendly w/ a local SE shop, they could set this up for you and take the stress off if you wish.

  • bertd
    Original Author
    10 years ago

    Thanks Tomplum. Lapping tool and compressor are on the way. Watched some videos on the Internet last night and I think I can handle it. Now that I've seen it done, it's not so bad. My valves and seats don't look too bad, but I'll know more once valves are removed. I saw one guy on the web demonstrating this process and he said that he gets numerous engines from salvage yards that simply needed tappet clearance adjustment and lapping to repair. Hope it works for me. Cold blast hitting here tonight and valve tools on the way, so I'll repost as soon as I know more. Thanks again!

  • bertd
    Original Author
    10 years ago

    Received lapping tool and spring compressor but weather has been terrible and hope to do valve job soon. I put piston at TDC on compression stroke and tried to shine a flashlight into top of valves to see if I could see any sign of light at all in the valve spring inspection area. None seen. It was pitch dark when I did this. Anyone think light should be visible if the valves are bad enough to prevent engine from starting. Also, I was concerned about partially sheared flywheel key as Tomplum mentioned. The flywheel magnet is just approaching the first edge of the coil with piston at TDC on compression stroke. Is this where it should be if timing is correct? Rather not pull the flywheel if not necessary. Thanks.

  • tomplum
    10 years ago

    It may be possible to see light through, depending on where the fault is . If the angle is wrong you may not. A bright inspection light in the port may do the trick. The news is to verify if the flywheel key has been damaged, the flywheel must really come off. I'm just full of joy today, aren't I? ;)

  • bertd
    Original Author
    10 years ago

    Thanks Tomplum. Haven't had time to work on the mower much due to weather and family issues. I did grind the intake valve stem down and it's now in spec. The exhaust was already on the high side of spec, so I only cleaned the carbon off of it. It was much easier to check the clearance accurately once the springs were out of the way.
    I didn't notice at first, but I noticed yesterday that there's a dark stain or "slooge" stain on top of the cylinder block at the bottom or lower side of the head. Head gasket looks ok visually, but that stain looks very suspicious, It does not just wipe off either. Maybe a leaking head gasket was or was part of the culprit. I ordered a new head gasket today along with misc. gaskets for carb, exhaust and other future needs. I also went ahead and ordered a flywheel key just in case. It was only like $1.25. Hope to have the parts within a week and get a break in the weather. As soon as I put it back together, I'll repost and let the world know the result. Thanks again!

  • tomplum
    10 years ago

    You seem to be on target here!

  • bertd
    Original Author
    10 years ago

    Receive all my parts finally, and had a warm day yesterday. After looking at the gasket surface of the head closer, there was no doubt that I had a leaking head gasket. I taped the corners of sheets of sandpaper onto a large piece of glass and smoothed the gasket surface area of the head. Started with 150 grit and worked my way up. This took some time. I was surprised how warped/uneven the gasket surface of the head appeared to be.
    I checked that old coil again and the readings were still off so I left the new one on the mower. The old one produced a spark, but meter showed bad readings as noted before.
    Torqued the head to spec and put her all back together. Started on 3rd pull and purrs like a kitten!
    Note to others that my head gasket was leaking on the bottom, and it was almost impossible to detect without removing the muffler and/or the head. If I had it to do over, I would have, if necessary, removed the muffler and sprayed carb cleaner along entire the gasket surface with the engine running before removing the head. However, I waited too long and couldn't even get the engine started. In my case, it worked out well because the gasket was definately leaking. Do yourselves a favor and check compression in the early stages of repair before throwing parts at one like I did. The low compression reading, along with Tomplum, got me on the right track. Thanks for the good advice. This site is awesome!

  • tomplum
    10 years ago

    Cool enough! Did you clean up the valves as well?

  • Mike Brandenburg
    8 years ago

    i am having the same problem with the head gasget. where did you find one

  • Marion Patton
    3 years ago

    I have a Kawasaki FB460V vertical engine on a Toro lawnmower. Where is the OHV cover you remove to adjust the valve clearances (Tappets)?

  • tomplum
    3 years ago

    You have to remove the cylinder head, carb, side cover and exhaust as this is not an OHV.

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