what will prevent a constant spark besides coil?

[adam123]

sj with some mods on it, my compression is 170 Out of the water sounds great. however, when i take off the front spark plug boot off while running it takes 2 to 3 seconds to die out, when i do it on the rear it dies out instantly.
after about 30 seconds to a minute in the water one cylinder cuts out (thats at least what it feels like) chokes and dies. It does not start right after, i have to give it 20 to 40 sec. and same thing happens but with in matter of seconds.
twin carbs
Lightened flywheel
protec CDI
I just put a new coil , but the problem remains. motor is being cooled. I think i don't have a constant spark, what to do next
please help

thank You,

 

[WFO Speedracer]

spark plug wires,and boots both go bad

 

[monkeyboy650]

check your s/s switch thats what mine did till mouth had me check the s/s. start easy then go deep

 

[chrisdoc0608]

in addition to the above, if you are sure that spark is your problem, have you tested your stator?

read this http://www.x-h2o.com/threads/37800

 

[WFO Speedracer]

Or the carbs most likely since it is twin carb.

 

[Kaveman]

Out of the water sounds great. however, when i take off the front spark plug boot off while running

Not a good way to check for spark loss on a pwc ignition system. Use an in-line spark tester set to between 4 and 6mm.

Occasionally when you remove a lead while running the engine the spark energy has nowhere to be released and will back track and take out a diode rendering the cdi inoperative or cause it to function improperly.

 

[adam123]

Man, i really appreciate the quick suggestions
Thanks again
The new ign coil came with wires, and boots. Got it from Jetski solutions.
-The carbs are ok i am sure.
-The s/s swith, i assume it is start stop switch. If it is the case, Is possible to cut of one cyl 1st? What am i looking for when i take it apart. (if it gets wet inside?)
-Kaveman, I hope it has not happened to it yet. If it did, wouldn't it be doing it pretty much all the time even when out of the water? how do i check if i fried the diode in the cdi? I will try to get the spark tester tomm.
-Chrisdoc0608 thaaaaaaaanks for the the link, i will get the analog meter tomm.

 

[chrisdoc0608]

to test the s/s switch trace your wires from the switch back and disconnect them. using a continuity tester you should get good continuity when you press the start switch between the start wires, same with the stop


the best way to check for the cdi is putting a known good one in and see if there is a difference,

 

[Kaveman]

Kaveman, I hope it has not happened to it yet. If it did, wouldn't it be doing it pretty much all the time even when out of the water? how do i check if i fried the diode in the cdi? I will try to get the spark tester tomm.

I have the cd service manuals from Yamaha for Waverunners. I just moved so everything is still packed away. I will try to find it and post the cdi testing process for you when I do.

Typically if you lose one cylinder it is not the cdi, usually a random fire, intermittent fire or none at all.

 

[chrisdoc0608]

adam, if you want a copy of the shop manual, pm me your email ill send you a pdf attachment

 

[adam123]

I just got done checking s/s switch, the digital meter was reading fat 0s, and 003.

 

[adam123]

I wonder if this pink wire should be connected to the loose black ground.
But it was like that when it ran i guess.
I guess i am ready to check the stator.

 

[chrisdoc0608]

i may be mistaken, but the pink wire was prob to your thermo for the head

 

[Kaveman]

i may be mistaken, but the pink wire was prob to your thermo for the head

Correct, as the loose black was more than likely the ground for the thermo sensor.

 

[adam123]

there r 5 wires coming out of the stater.
How do i check it?

 

[chrisdoc0608]

did you read the link that i posted? if you take the ohm readings that are on that post and use them as a guide, you simply connect you ohm reader to the corresponding color wires and check to see if your ohm reading matches what the specs should be

 

[adam123]

Everything tested within the range , except the "lighting" coil (or rectifier),
But according the the link it causes the battery not to get a good recharge.
I am replacing it, any suggestions who I should order from?
Will That FIX my problem U think?

 

[WFO Speedracer]

It will not fix your problem,order one if you like,I say you need a spark tester so you can run it and see what the spark is doing before assuming something is bad.

 

[chrisdoc0608]

It will not fix your problem,order one if you like,I say you need a spark tester so you can run it and see what the spark is doing before assuming something is bad.

i agree, dont go and throw parts at it until you know for sure what is wrong with it

 

[adam123]

In order for me to check the spark would be on the flat water, Lake Michigan doesn't get too flat. I am going to replace my fuel filters, and cdi I 'llkeep one the side.