2002 Yamaha 60TRLA CDI problem?

[99yam40]

Have you made sure all cylinders are sealing properly yet?
Hard to make a motor run well if compression is not there.

As I said before spark tester and timing light are simple to find at any auto part store to make sure about those. voltage measurement is the best way to see what is going on but is not necessary unless you see a problem with spark tester or you are not sure of what you see with it

[pookiegus]

I checked The compression first and each cylinder measured 120psi

What do I do next if one cylinder is lower voltage? Start testing inputs and outputs to the CDI?

If all the cylinders get the same reading - couldn't one cylinder still fire at the wrong time because a sensor is bad or the CDI is bad? Or is that pretty rare?

[99yam40]

never seen it happen before, but can test it with the timing light.
Just find and mark TDC on all cylinders and then check with timing light.

Weak spark should be investigated by testing as you said

[rodbolt17]

the CDI box does NOT amplify anything.
it simply rectifies an AC voltage,stores it in a CAPACITOR and discharges said capacitor when the SCR is triggered.

in this case two pulser coils trigger cyl 1&3, cyl 2 is trigged by internal CDI circuitry and the crank position sensor.

remember the CDI unit DOES NOT make voltage.

you have TWO seperate ign parts.

you have ign PRODUCING.

you have ignition CONTROLING.

which failed?

thats where my Kv tester is so so so so so,did I mention, so handy.

so, hypotheticaly, I walk up to you rig.
start it,let it warm up.
I test secondary Kv, takes 30 seconds tops.
all are at say 8 Kv.
thats what I expect.

now I dissconnect the timing link and move it manually while watching ign timing with my timing light.

it moves from about 7*ATDC to about 21* BTDC, thats what I expect.
I have spent 5 min looking and I just eliminated both sides of the ign system.

this aint rocket science.

[bajakeith]

Waekon 76760

I have ALL kinds of CDI stuff,, but I ordered this 76760 Monday and waiting for it to show up...YEE HA !! new toys !!!

[pookiegus]

What kind of meter can handle the coil voltages?

Most of the ones I've found are only rated up to 1000 Volts. . .

This is what's hanging me up right now. I have a meter that can handle up to 1000Volts - am I going to fry it connecting it to the coil?


Thanks for all the help. . .

[rodbolt17]

Ill say it again.
Google "Kv tester".
the K in Kv indicates Kilo(1000) and the v indicates voltage.

you can find them for 30 dollars to 200+ dollars.

[pookiegus]

Problem Resolved - Finally

After several hours of running the boat at about half power with the CDI disabled we brought it to a Yamaha tech. He listened to all that I had done but was convinced it was the fuel system specifically the carbs after testing all the components in the ignition system. He took the carbs apart and the fuel enrichment system on the second and found the gaskets were falling apart and one of the jets in the third carb was a little clogged. He also installed a water fuel separator and large fuel filter on the built in gas tank.

While he was working on all of this I decided to order a new ignition switch to replace the one that had been giving me problems. The key was hard to get out and the start position didn't work at all. I had temporarily wired a push button switch to use as the starter. None of the gauges worked which I felt could be caused by a bad ignition switch as well.

When I went to pick up the boat I had him start it before I paid. The motor fired right up but still exhibited the same bogging at anything above idle. I showed him how if I disconnected the CDI (Yellow Wire Circuit) the Motor would rev up to higher RPMS. He was stumped and so was I. We were in almost exactly the same place with the motor as when I dropped the boat off but now I owed him $900 for parts and labor. The other thing I should mention is it took him exactly 6 weeks to get to this point and I just wanted the boat. The motor did start quicker and run smoother but still sounded like it was misfiring and bogging out at anything over idle. If I disconnected the CDI yellow wires the motor reved fine but only to about 3000 RPM.

I paid reluctantly and took it home. Then I installed the new ignition switch and lo and behold the problem was solved! I didn't think the ignition switch had anything to do with CDI or the ignition timing! The new switch also brought all the gauges back to life.

Could the switch have been the problem all-along?

[99yam40]

if it(switch) was trying to ground the system then yes it could be a problem.
If you find a problem. fix it, there is no reason to just try and bypass it

[pookiegus]

If you find a problem Fix it

Good advice - and my new mantra. . .