1984 yamaha 150 2stroke

[jerry12@3]

I have seen a previous post where someone had a 24 ohm reading on their stator.I have the same issue and manuel says for a 84 it should be 127.it also says a 86 should be 24 ohms.I am having intermitted no spark to spark on the tree cyl on the left .Not sure whats going on.Any ideas would be helpful.thank youI have changed the cdi and stator.

 

[jerry12@3]

Just wanted to add more info.after changing the cdi i went from no spark to spark on five cyl .nothing on bottom right .the next morning after a cold night i had no spark on right side.????I have swapped coils trouble did not move.clean grds by cdi.still no fire on right side.

 

[99yam40]

I know nothing about a motor that old, but the service manual for the motor should give testing procedures.
Peak voltage readings into and out of the CDI should give you some direction to be looking.
how many pulser coils does this old motor have telling the CDI when to fire the plugs?
my 1999 C40 has 3, one for each cylinder

 

[jerry12@3]

Not sure if it has one for each set of 2 coils or 6 .The motor had been worked on before i bought it.The wiring had been repaired below the oil tank.

 

[QBhoy]

Not sure if it has one for each set of 2 coils or 6 .The motor had been worked on before i bought it.The wiring had been repaired below the oil tank.

See above post from 99yam. Asking about the often forgotten pulsar coils. Have a look at them, if applicable.

 

[jerry12@3]

I know nothing about a motor that old, but the service manual for the motor should give testing procedures.
Peak voltage readings into and out of the CDI should give you some direction to be looking.
how many pulser coils does this old motor have telling the CDI when to fire the plugs?
my 1999 C40 has 3, one for each cylinder

 

[jerry12@3]

It does have 6 trigger wires .not sure if thats the same.

 

[99yam40]

mercury calls them triggers,
Yamaha calls them pulsers.
if the CDI does not get the signals to fire each plugs, they will not fire.
so maybe you should test to see if the CDI is getting the signals

 

[jerry12@3]

mercury calls them triggers,
Yamaha calls them pulsers.
if the CDI does not get the signals to fire each plugs, they will not fire.
so maybe you should test to see if the CDI is getting the signals

Thank you i will start there.I have also ordered a cdi.

 

[QBhoy]

mercury calls them triggers,
Yamaha calls them pulsers.
if the CDI does not get the signals to fire each plugs, they will not fire.
so maybe you should test to see if the CDI is getting the signals

99yam. Am I right in thinking that these things I’ve mentioned, are under the flywheel and not apparently obvious to some ? Maybe I’m thinking of smaller Yamaha motors

 

[99yam40]

yes the pulser coils are under the flywheel along with the charge coils ( that charge the capacitors in the CDI)
and lighting coils (that power lighting/and battery charging and other 12 volts needed on the motor)

 

[airshot]

Double check all connections for rust or corrosion. On older motors this is common, all connections should be nice and shinney clean. Can't say that is your issue, but intermitant problems are often caused by poor connections. Good luck!!

 

[jerry12@3]

Thank you for all the info