2007 Yamaha 70TLR PrimeStart Issue

[99yam40]

the lighting coil provides AC voltage to both the primestart heater unit and the RR,
the RR does not send voltage to the heater unit
the RR takes the ac voltage ,rectifies it to DC and regulates it to 13-14 volts to charge the battery

Boscoe, I was just refering to your comment about it still running rough with the valve manually closed, he said that was not what was happening.

He has yet to prove the heater unit is getting Voltage while motor is running.
the lack of voltage getting there is the most likely problem as far as I can tell if the needle moves when tested off of the motor

[Whaler94]

I just did. Which leads me to believe that maybe, just maybe, too much fuel is getting through the system when the valve is in the automatic position. Maybe there is debris on the needle seat that is preventing the needle from fully seating and closing off the flow of fuel when the motor is warm. Allowing too much fuel and resulting in an excessively rich mixture.

OP says the Primestart heater and needle valve are working. For some reason it seems to not be getting the job done. If indeed too much fuel is flowing and causing the ruff running issue.

OP might want to go and review the dangar prime start video.

Heck I don't know. Just guessing. Hard to trouble shoot in person. Harder still to do it from a distance.

I watched the Dangar PrimeStart video over the weekend, which is excellent. I followed his procedure for disassembling and testing the unit and everything checked out perfectly. the mechanism was very clean. Seeing it work on the 12V battery tells me that the unit itself is functioning properly. It just doesn't seem to be getting power in the engine, which is where I get totally lost.

[Whaler94]

the lighting coil provides AC voltage to both the primestart heater unit and the RR,
the RR does not send voltage to the heater unit
the RR takes the ac voltage ,rectifies it to DC and regulates it to 13-14 volts to charge the battery

Ok I'm starting to get a better understanding now. So withstanding all of that. Would a not functioning lighting coil have any other ill effects on the engines performance other than the PrimeStart not working?

[99yam40]

I will repeat the RR charges the battery

[boscoe99]

Ok I'm starting to get a better understanding now. So withstanding all of that. Would a not functioning lighting coil have any other ill effects on the engines performance other than the PrimeStart not working?

None whatsoever. The lighting coil in your model does three things and three things only. Provides AC power to the Rectifier/Regulator and to the Primestart thermovalve component while also providing the tachometer reference signal.

Other coils within the stator assembly provide electrical power to operate the motor.

[pstephens46]

the power comes from the lighting coil and is AC not DC
It is tapped in before the Rectifier/regulator.
so voltage will not be 12 , it should be higher depending on how fast the motor is turning

I learned something today. I never realized the Primestart heating element was powered by AC. Danger was able to bench test with DC? I thought I had watched that video. I don't recall him mentioning AC versus DC.

[boscoe99]

I learned something today. I never realized the Primestart heating element was powered by AC. Danger was able to bench test with DC? I thought I had watched that video. I don't recall him mentioning AC versus DC.

Keep on learning. It is a never ending process. Or should be IMO.

You forgot the first rule of Yamaha's. They are all created equally but some are more equal than others.

OP's model uses AC power to heat the PS thermovalve directly via the lighting coil. Other Yams use a dedicated AC coil. Other Yams might use AC/DC power from the R/R.

In the case of the Primestart thermovalve it uses a simple resistive circuit to heat it up. Does not matter if AC power or DC power is used. On some stuff it does matter.

[Whaler94]

Thanks very much for all of the replies everyone. My friend and I are hoping to test everything tomorrow or sometime in the next few days. I'll report back once we get some results.

[Whaler94]

So my friend and I tested the resistance of the lighting coil according to the manual. Our results showed a dead short where resistance should be 0.57-0.85ohms. However, the lighting coil on this engine has a green plug with two wires (one solid green and one green/white). The shop manual shows bullet connectors and not a plug. I tried to attach photos, but didn't have any luck, so I attached a link to the same part that shows the green connector. We haven't tested running voltage yet because of the cold weather. The questions is; is the pigtail connection further up the wiring of the lighting coil giving us an issue with testing? We tested using the female portion of the green plug, but that only goes to the two green - green/white wires and not the red one up further. Is this dead short an indication we have a bad lighting coil? We used an analog meter per the manuals instructions.

http://www.boats.net/parts/detail/ya...533-01-00.html