F115 2001 Cold start problems

[cjanderfors]

I have a F115 4 stroke from 2001, that starts as expected when I turn the key to start.

After ca 10-30 seconds the engine starts to bog and then it dies after several attempts when the engine in warmed up I have no issues it runs and starts as it should both at idle, slow speed and cruising speed.
When the engine starts to bog i can push the powertrim up or down and then the bogging disappears by doing this I can keep the engine running until it warms up.

Fuel lines are new, the engine charges as expected 14V

any ideas what to look for?


Thanks

[99yam40]

maybe hitting the PT&T pull more current and fixes a bad connection from the batty.
clean all battery connection + and Neg

[cjanderfors]

maybe hitting the PT&T pull more current and fixes a bad connection from the batty.
clean all battery connection + and Neg

Thanks for the reply and suggestion yes I had the same thoughts I went over the battery connections, and cleaned them and also took out the battery separator/disengage switch. But unfortunately no difference.

[TownsendsFJR1300]

Someone recently had a similar issue as I re-call.

Turned out to be some failed wire(s) in the area where the lines bend/move with the T&T. Not visible as it was inside the insulation..

You may try manipulating that harness while it's acting up (with another driver operating the boat) and see if that makes a difference...


.

[cjanderfors]

Someone recently had a similar issue as I re-call.

Turned out to be some failed wire(s) in the area where the lines bend/move with the T&T. Not visible as it was inside the insulation..

You may try manipulating that harness while it's acting up (with another driver operating the boat) and see if that makes a difference...


.

Thanks Good tip i will look at that,
Also worth to mention i replaced the voltageregulator as i had a charge problem before the winter, this is now the first times i use the boat after that.

[cjanderfors]

One theory is that when I press th PT buttons the ECU is compensating for the high current needed by the PT motor.
And this is why the engine runs better when cold by pressing the PT.

If so it's the cold start/choke function that doesn't work, does anyone know how to troubleshoot it? I assume its con*****ed by the ECU?

[99yam40]

maybe hitting the PT&T lower voltage causing something strange to happen in some reading from sensors

[cjanderfors]

Problem solved,

What caused this was the 3rd party voltageregulator I installed this winter, i didn't se the connection as it charged ok, with an original Yamaha VR it all works fine.