BLES wrote:KE4AVB wrote:Bles, Have you verify this yourself or is ti base on what the customer is reporting. If just the customer reporting this it might be plugs fouling to a point where they are shorting out. I do know Kawasaki engine like a heavier oil than the Briggs engines. Something like 20w50.
Neighbor called me today and I ran over as it was missing and loss of power. I only saw/heard it run. Didn't test anything except to check exhaust temps (both sides were the same). He claims the plugs don't look very bad (dirty/fouled) when he changes them. Has been through about 10 sets before he called me.
I will look at it next week likely. He's had it since new (late 90s) and it now has about 1100 hours. Runs nice until the missing starts.
Thanks guys for your ideas.
BLES
I'd suggest starting by doing some homework and make sure exactly which spark plug (BRAND AND Number both!) recommended for it by Kawasaki (Bear in mind different model year engines might need different plugs) and also verify the required plug gap for the engine.. then make sure the new plugs meet all those specs.. If they do then I'd be thinking a marginal ignition system (ever been serviced? maybe too much coil air gap? some rust? loose wiring connections?) but if plugs are not the right ones (They'll probably be wanting NGK and bear in mind that some NGK Specs have no equivalent in Champion or Bosch or Denso.. and vice versa.. ) then you wanna get a couple , and make sure they are gapped to spec, and go from there..
Other things that cause premature fouling (especially the kind that cause dead shorts) - Some fuel additives that may have any metal or carbon to them (builds up on insulator, doesn't burn off, and gives short path to ground that bypasses the plug gap) , Then there's the matter of torquing plugs properly (overtighten them and you can crack the insulator, which obviously allows a dead short to ground) - even adjusting the gap by whacking the electrode on a hard surface (to close gap) or one of those "coin" gappers or screwdriver (prying on center electrode for leverage to open gap) can cause cracked insulators too.. so you wanna use the correct plug gapper tool (metal tang with slot to fit over ground electrode to bend it in or out)..
Of course, there's always the possibility of the changing of plugs being a Red Herring and you may find the plug boots (hardened from heat or cracked, once they collect enough dust from EMF, they start shorting to ground.. and removing them and putting them back is what was "fixing" the problem..) or the plug wire terminal ends (or plug wires) corroded, broken or rusted - again R&R of the plug boots temporarily "fixes" the problem.. In those cases, may need to replace the plug boots and/or terminals.. some of em are just resistor caps (you can thread em on and off the plug wires) while others, might not even be replaceable and require whole ignition coil (unlikely for a Kawasaki, but pretty common on the china clones)
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)