FH500V kawasaki dying without choke... (FIXED)

[boomerang]

At the risk of sounding like a moron, I will say that initially on startup it was not uncommon to see some smoke, and through some of my more recent work, it seemed a little more frequent. Nothing terribly, but just enough that it was visible.

Based on a how to article for dummies like me: http://www.doityourself.com/stry/6-symptoms-of-ignition-coil-failure#b

That would seem to suggest a coil pack is a definite possible culprit. As there are two plugs on this guy, I'm wondering if I should just replace both coils. It's a $100, but i am sure it has not yet been done on this fella. Any tests I can do to confirm a coil issue?

Coils I am looking at:
http://www.amazon.com/Kawasaki-Ignit...ignition+coils

I understand what you're doing, I really do. Brainstorming trying to come up with the source of the problem. In some ways your thoughts mimic my thoughts. But the difference between a mechanic and somebody that just fixes things, is that a mechanic diagnoses the problem and replaces or adjusts only the part that is creating the problem.

Stay the course on this one. Fuel pump first since you've already ordered it. There is a very simple procedure outlined in the manual for checking the fuel pump and I would have done that before spending the money for a new one. But you've ordered it so you might as well replace it. I read through the service manual a little today and they mention checking the intake manifold for cracks. Now, that doesn't mean that it's a common problem or that you should order an intake manifold, it just raises a question that is answered by checking the manifold as part of your troubleshooting process.

Do not replace the coils on a whim. Do not throw parts at a problem. Page 9-18 shows you how to test the coils. I wouldn't be replacing coils without checking them and the chances of both coils going at the same time is miniscule.

Smoke? What color smoke?

Do you know how to read a sparkplug? When it's running bad, shut if off and pull them out and take a look. If you don't feel knowledgeable enough to interpret what you see, post pics if you can.

I laid out the steps I would follow earlier. I still stand by my suggestions. They are the steps I would follow if the mower were in front of me. Cleaning the carb would have been one of the last things I tried. If the mower won't start at the beginning of the season, the carb may be a suspect. If the mower starts running poorly after running well, I don't immediately suspect the carb. Gasoline is a fantastic solvent.

You're thinking and that's good. The hard part is applying enough logic and not succumbing to throwing parts at a problem willy-nilly trying to fix it.

 

[mvbighead]

Well, the new fuel pump arrived. Connected it, and it started spraying fuel. Took it off, disassembled it and reassembled it, and ran the mower for about 10 minutes, and then it started cutting out again.

The fuel filter (clear) was full of fuel, so I am pretty sure at this point fuel is not the issue. And as the I have already cleared and rinsed out the tank, I don't suspect fuel quality to be an issue, so I think it safe to assume I have that issue ruled out. (Correct me if I am wrong though)

And yeah, I don't really intend to just buy the coils, but figured I would start trying to rule them out. Spending $10-15 here or there on this or that is a pretty simplistic approach, but when it comes to $100 plus items, I figure I'll do what I can to ensure they're problematic. And mostly, asking questions to see the next steps.

I will say that it seemed to be operating with full force this time, but it still died.

As for reading plugs, no I am not very good at that. I may pull the plugs tomorrow and check the gap and knock down to .030 (not sure, but at one point I thought I had found .035 but lately all I seem to find is .030).

Bad thing is that I have plans to go out of town this weekend, so not sure how much time I can put into this over the weekend, but I'll keep messing with it day after day until something gets figured out.

 

[boomerang]

Well, I know you and others are not buying my valve adjustments suggestion, but I would be doing it as the first thing after a visual inspection. If the clearance tightens up as the motor warms up, and it's too tight to begin with, there is a good chance a valve or valves are hanging open. Couple that with the factory recommendation to remove the heads to clean the carbon and check the valve sealing every 300 hours and I would be all over that. Kawasaki is telling you this is a potential problem.

Think about the geometry of the valve train. An exhaust valve gets very hot. It will eventually pound itself deeper into the valve seat. This tightens up the valve clearance. As the mower warms up, the clearance lessens to the point that the valve never closes. The fuel laden intake charge is escaping out the exhaust valve and that leans out the intake charge. To top it off, you're losing compression and compression = power. Now you've got a double whammy going on. Not enough air and not enough fuel to support the rpm the motor needs to run at. It can't run with the power required at the rpm required and the end result is that it's running bad with nothing in particular to point to.

You have a PM.

 

[mvbighead]

Well, I know you and others are not buying my valve adjustments suggestion, but I would be doing it as the first thing after a visual inspection. If the clearance tightens up as the motor warms up, and it's too tight to begin with, there is a good chance a valve or valves are hanging open. Couple that with the factory recommendation to remove the heads to clean the carbon and check the valve sealing every 300 hours and I would be all over that. Kawasaki is telling you this is a potential problem.

Think about the geometry of the valve train. An exhaust valve gets very hot. It will eventually pound itself deeper into the valve seat. This tightens up the valve clearance. As the mower warms up, the clearance lessens to the point that the valve never closes. The fuel laden intake charge is escaping out the exhaust valve and that leans out the intake charge. To top it off, you're losing compression and compression = power. Now you've got a double whammy going on. Not enough air and not enough fuel to support the rpm the motor needs to run at. It can't run with the power required at the rpm required and the end result is that it's running bad with nothing in particular to point to.

You have a PM.

So you're thinking the valves could be starting off tight, and then getting tighter? Just curious, but most of the videos I look at suggest that the valves get loose. Any how, I will be taking a look when I have the time to tear it open. That'll require removing the exhaust on the one side to get at stuff, but at this point, I gotta do something.

 

[boomerang]

When you take the exhaust off, take a good look at the exhaust ports and the muffler for carbon buildup. I've read it both ways, that in some motors the clearance gets greater and in some it gets tighter. I have no clue which way these motors end up. Everything gets larger as it warms up but some things are steel and some are aluminum. So there are a number of things in play.

 

[mvbighead]

When you take the exhaust off, take a good look at the exhaust ports and the muffler for carbon buildup. I've read it both ways, that in some motors the clearance gets greater and in some it gets tighter. I have no clue which way these motors end up. Everything gets larger as it warms up but some things are steel and some are aluminum. So there are a number of things in play.

Not much carbon build up that I could see.

I did do the valve adjustment, and one was extremely tight and one or two were quite loose. I got everything to be just lightly loose (which seems to be the desired state of things according to the interwebs) so hopefully that helps.

On of the sides had a leaking/cracked gasket that apparently been patched with red RTV sealant. I cleaned everything off and created a new gasket with blue RTV sealant as Oreilly did not have the right gasket. I'll probably just follow up tomorrow as the cure time on the sealant is 12-24, and in the interest of getting this right, I'll let it cure properly before I do anything else.

 

[mvbighead]

Well, that didn't seem to fix it. It did 'seem' to be running with full power, but it still surged. There at the end (about 3 minutes or so) it surged up and down, sputtered way down, ran for about 10-15 seconds, then died off.

Going to see about taking all of the cover off to run the multimeter on the coils. At this point, I figure it has to be the coils... either that, or something major. I did record a video, but I need to convert .mov to something more suitable for upload.

Well, it uploaded fine as MOV, just has to convert on youtube's end I guess (I am not used to iPhone stuff.). Here is the URL:

http://youtu.be/G2mLJ2o2gv0

Skip to the 2:00 mark to hear the surging.

 

[Zorba]

After you tried running it with no air filter/exhaust? Probably won't hurt to try it if you haven't already.

I am not sure if the mower has an auto-choke, but if it does maybe something is going on with it? I had an edger that was surging a lot, and I could see the auto-choke moving, I just cleaned all the mechanics really well and it seemed to fix it.

 

[mvbighead]

After you tried running it with no air filter/exhaust? Probably won't hurt to try it if you haven't already.

I am not sure if the mower has an auto-choke, but if it does maybe something is going on with it? I had an edger that was surging a lot, and I could see the auto-choke moving, I just cleaned all the mechanics really well and it seemed to fix it.

Yep, I had all that off at one point and it was no help.

Not sure about an autochoke. I did do some reading, and it seems coils can be a somewhat common problem with some of these:
http://www.lawnsite.com/showthread.php?t=293008

 

[mvbighead]

Well, I tested compression and both sides were at 135 dry.

At that point, I took the cover off and the coils were both extremely dirty. I tested the coils and the reading from A to C on one was 10.5 and 13.5 on the other. From B to C it was 2.3 m on one and 5.5 m on the other.

I used compressed air to clean everything off (it was not very clean by any means), and tried again with the same results.

At this point, the readings from the B to C connections were not at all what they were supposed to read (though I am using a standard multimeter and not the Kawasaki approved $200 tool). In addition, with the readings being quite different, and the spark plug boots being quite worn, I figure replacing the coils makes sense at this point.

If that doesn't fix it, I figure I have exhausted my options of what I can do and will leave the rest to a pro. I suppose I could pull the carb and give it an overnight soak in hopes that it does something, but I can't see the carb causing it to stall off and die (the flutters in idle I get, but not dying off).

This may or may not be the right path, but as the two readings are so different from one another, I figure $110 towards a mower that runs in excess of $1000 used is not a terrible investment when considering the tool to do the proper test runs more than two coils.

 

[mvbighead]

Well, coils arrived. Got them installed and it took MANY pulls just to get the thing to start.

Finally did, and it died in the same fashion.

I'm missing something, and I am not sure what.

I did pre-test the new coils and both registered 18K and about 6M so while it is an improvement, it didn't matter. Still not measuring 2K or anywhere close, so I guess that is the difference with using a standard multimeter and not some fancy tool from Kawasaki.

 

[mvbighead]

Well, on a whim I decided to take the carb out and spray it with cleaner. I took more off than I did the last time and figured out the I probably didn't clean the port that settles in the bottom of the fuel bowl. I sprayed everything off that could, and now I have changed the symptoms, so at least I getting somewhere.

Only trouble is, at this point, it dies completely without the choke. I must have a screw too tight or something, but the only screws I adjusted were on the fuel bowl. I didn't screw it very tight, but I figure I must need to adjust that in some way.

Thoughts?

 

[mvbighead]

Well, I bought Berryman's Carburetor Chem Dip, soaked it last night, rinsed it out and dried it off, and was able to mow the yard without issue. Next time I clean the carburetor, I'll be sure not to just blow air through it.

 

[dmaer]

I have the same problem...did you take off the plastic parts prior to Chem Dipping?

 

[mvbighead]

I have the same problem...did you take off the plastic parts prior to Chem Dipping?

Yep. Pretty simple really. Slide the pin out of the float, and carefully remove the other piece that is hanging from the thin strip of metal and set aside.

I did end up having to dip the carb a second time because the problem resurfaced after one full mowing session. I let it soak for a few days the second time, and have yet to have another problem <knock on wood>.

My dad suggested it could be a problem with ethanol gas causing deterioration in the fuel lines leading debris into the carb and plugging things up. I am not 100% sure of that, but it sounds feasible enough to me. The problems started at the end of one mowing session, which leads me to believe that something came loose and plugged the carb (not a gradual build up of varnish/gum or whatever).

Anyhoo, so far, so good.

 

[LTC8K6]

You could replace the lines and the fuel filter with ethanol safe parts.

 

[mvbighead]

You could replace the lines and the fuel filter with ethanol safe parts.

I did replace the fuel filter earlier this season. But yeah, the fuel lines may need to go. Thus far things have been smooth, but I will say I probably messed up a carb adjustment because it is a real PITA to get it to start for the first time. Usually was about a 2-3 pull mower, now it seems like 15-20 pulls, but it eventually fires up and runs for 2-3 hours.