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KKassel, Marine Mechanic
Category: Marine Electronics
Satisfied Customers: 1736
Experience:  Worked on marine electronics for over 8+ years and counting
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no output voltage from cdi unit

Customer Question

no output voltage from cdi unit
Submitted: 4 years ago.
Category: Marine Electronics
Expert:  KKassel replied 4 years ago.
-Could you explain your situation a little more?

What motor
Customer: replied 4 years ago.

1989 yamaha excel 225 hp no spark to plugs

when checked with spark tester


so i started from the coils with another expert and


we got stuck when there was no output after replacing the first cdi with


a spare and removing the kill wire from the cdi box


all input voltages seem ok going into the cdi


before doing the voltage test i also performed the resistance test from


the manual all was good.


luckly i have spare parts from my old motor to learn with.








Expert:  KKassel replied 4 years ago.
And you swapped the coils to Make sure

Did you clean the coils grounds also
Customer: replied 4 years ago.

i cleand the coils brass ground surface that the screw mount threw to the bracket with a brush before i installed it for good contact .


Expert:  KKassel replied 4 years ago.
Ok and what where the trigger readings?
Customer: replied 4 years ago.

trigger wht/red to wht/grn=2.9v

wht/blk to wht/blu=3.8v

wht/yel to wht/brn=3.0v

stator low=85v








Expert:  KKassel replied 4 years ago.
That high speed seems low but that kicks in at 2000 rpm

Have you swapped the cdi yet?

If so its the stator
Customer: replied 4 years ago.

yes i swapped the cdi two days ago

how does the stator keep the cdi from changeing ac input


wave from being recterfied to 58v and discharge to the primary coils


it dont make sence.



Expert:  KKassel replied 4 years ago.
its a/c volts

there is a capacitor in the cdi box that stores up volts
Customer: replied 4 years ago.

but you said change the stator assy. and its doing what its suppose

to do why do you want to replace it


i dont have a bearing puller to remove


the fly wheel

Expert:  KKassel replied 4 years ago.
Ok because the high speed stator should have more than 14 vols

If you swapped coils, and cdi box, then it's either trigger or stator

Triggers need only .7 volts to work

Stator should be at least 50v
Customer: replied 4 years ago.

yes and i am getting 85v @ low spd and 14.4 @hi spd maybe even more if the fly wheel spins faster but 50 v no way i look @ the cdi electronic spec and they say 16v

where did you gett 50v from the last expert said
14v was min. from oem spec. tech has more than 5 years experience

do you have a copy of the spec or web site so i can see what you are talking about.


Expert:  KKassel replied 4 years ago.
Cdi could be wrong, some times they post wrong info

Try it with the all plugs out so it spins faster and see if it increases

What's the ohms
Customer: replied 4 years ago.

what do you mean voltages or ohms

i have to remove the wires to measure the ohms

Expert:  KKassel replied 4 years ago.
You unplug them from the Cdi box and test them
Customer: replied 4 years ago.

you didn,t answer my question what spec are you using that tell you

50v for hi sped coil i all ready checked my coil .25pri 2500sec. 5k cap

Expert:  Walt-mod replied 4 years ago.

I’m a moderator for this topic. It seems the professional has left this conversation. This happens occasionally, and it's usually because the professional thinks that someone else might be a better match for your question. I've been working hard to find a new professional to assist you right away, but sometimes finding the right professional can take a little longer than expected.

I wonder whether you're OK with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you.

Thank you!

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