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If you have already put new spark plugs in your motor, you need to do a few more tests before you should accuse the CDI.
If you have a timing light, connect the timing light to the failing cylinder and watch what it does when it fails. Does the light go away? Does it speed up?
Then compare it to the other cylinders that you think are working ok.
If the light goes away, you could have a bad coil or pulsar. It could be the CDI, but you can not know for sure yet.
If you have a peak reading voltmeter, you could compare the outputs of the pulsars as well as comparing the inputs to the spark coils. If the voltage is the same for all cylinders going into the CDI unit but not the same coming out, then suspect the CDI. If the outputs are all the same, then it is probably a coil.
You could always switch coils to verify, if that is the case. You may have to use jumpers to switch things around.
If the light pulses faster, you could have issues with the pulsars or the CDI could be crossfiring and firing at incorrect times on that cylinder.
Mike
There are actually three pulsars....one for each cylinder in one unit. So, it is possible that one might have an internal high resistance short to another. If you do not have the manual, at least check the circuit diagram in the back of the owner's manual and you will see what I mean. http://cdn.powerequipment.honda.com/marine/pdf/manuals/31ZV7614.pdf
The magnets on the flywheel are energizing the exciter coil, which provides the high voltage to all the coils through the cdi. So, if two cylinders are good, the exciter coil is probably putting out the correct voltage.
Back to the pulsars..... If you do not have the proper tester to measure the outputs (which are very small.... .5v or less), check each lead to ground with an ohm meter...and compare that way. Also measure from pulsar output lead to the other two leads. Those measurements should be the same.
One other thing to check are the timing marks to be sure that the timing belt did not jump a notch.
Mike
The book says they should be anywhere from 290 -325 ohms. So, that may not be your problem.
Do check ohms between any of those leads and engine ground. It should be an open circuit. If you do get some resistance, then there is an internal short to ground.
Mike
What differences did you see using a timing light?
If no differences, then you may not have a spark problem. The spark in Hondas is very small and many times are mistaken for bad spark.
Your problem could be as simple as plugged idle circuit in the bottom carburetor. One way to check (that works sometimes) is, once you get the motor running, disconnect the choke linkage between all of the carburetors. Then way, you can manually activate the choke in any one of the cylinders. When the cylinder is failing, try partially pulling out the choke (on the front of the engine) to activate the bottom choke and see if the engine picks up in rpm. If it does, then you have a carb issue. If you activate the choke on one of the good carburetors, then the engine should bogg down a little.
Mike
Yes. The inside should be clear. The hole is very small. The fuel for idle goes up the tube into the top of the carb and gets combined with air from the idle her in the front of the carb. It then goes to the little pin holes at the rear top on the venturi.
Most brake clean or carb clean cans come with a little straw. Stick that straw into that hole where the long skinney tube goes and make sure you have good flow out of those pin holes. Spraying through the idle jet should do the same thing. If you can remove the idle mixture screw...it It should do the same thing from there. If not, then you have to clean out the pin holes with small wires.
The small tube ...aka jet set...is sometimes hard to clean well, so usually replace them if they are clogged.
Mike
I just did the chock test, running I engage the botom Choke it speeds up. The other 2 manual engaged start to flood and slow down. So I think when running and it getting rough to have to go to idle, its running itself out of fule on number 3. Time for jets. I will try to clean it first but def order a new set. Thank you sir. I will keep you posted. This is what happens when a 2 stroke guy has to learn. Thank you man!!!
