90HP 2 stroke won't switch off

[CharlieH]

I have a 90HP 2 stroke (2005 model) that when you turn the key off still continues to run. The only way to stop it is to disconnect the fuel. As I have two engines I swapped over the cables and ignition switches and have the same problem with the same engine. The kill switch tests fine. The other engine runs fine with both ignition switches so it has to be a problem with the engine any suggestions please?

[rodbolt17]

dissconect the white wire at the CDI.start the engine.
ground the white wire from the cdi to a good block ground.
engine should quit.

[CharlieH]

tried this and the engine keeps on running. If you activate the kill switch same thing, the engine keeps on running. The kill switch doesn't stop the other engine either. If you disconnect the main wiring loom on the 'faulty engine' then the kill switch works fine with the other engine (1 kill switch does both). So it must be at the engine end do you know where the ground wire connects at the engine end?

[CharlieH]

Found the problem - it was a brake in the white wire in the wiring loom itself. No chaffing or outer cable damage so must have been a manufacturing defect.

[99yam40]

If that broken white wire was the problem then what Rodbolt17 posted to try should have turned the motor off, or did you not try it the way he said?

maybe grounding the terminal where the white wire was attached to CDI would have been the ticket

[CharlieH]

what I did was to disconnect the white wire at the switchand connect it to a cable and ran that to the chassis of the engine? Oops just realised what I did wrong thanks

[99yam40]

Was your ground jumper hooked to the CDI side?
If not it could not ground the CDI spark voltage to stop the motor

[CharlieH]

now realise what I did wrong - thanks guys

[Drewgars]

Yamaha 130 2 stroke won't turn off

Hi.

I have a Yamaha 130 2 stroke That also won't turn off . Reading the below I was wondering how you disconnect the white wire from the cdi? Do you have to cut the wire before the harness that connects to the cdi?. I have tested the kill circuit between control box and main wire harness on engine and all ok so I think problem is somewhere on engine .

[boscoe99]

Hi.

I have a Yamaha 130 2 stroke That also won't turn off . Reading the below I was wondering how you disconnect the white wire from the cdi? Do you have to cut the wire before the harness that connects to the cdi?. I have tested the kill circuit between control box and main wire harness on engine and all ok so I think problem is somewhere on engine .

You have a different model Yamaha than the OP does. Or did. This is a four year old post.

Anyhow, what you can first do is to uncouple the connector close to the CDI box and then do a continuity check to see if the white wire to the connector, on the harness side, is grounded when the kill switch is activated or the key switch is turned off. It should be. If so, then disconnect the white wire from the connector on the CDI side. With the motor running ground the white wire and see if the motor stops.