Primestart issue 9.9 FT4 1998 AXE

[99yam40]

Boscoe, does the primestart heater get tied into the unregulated AC output of the lighting coil before it hits the RR?
I am thinking it does, but just wanted a confirmation for the OP

[boscoe99]

Boscoe, does the primestart heater get tied into the unregulated AC output of the lighting coil before it hits the RR?
I am thinking it does, but just wanted a confirmation for the OP

Most Primestart devices that I have seen get their power from the lighting coil.

In this model it does not appear so. Actually, this is the first model that I have come across that uses what is called a valve heater coil.

From the illustration below it looks like a charge coil output, a lighting coil output and a valve heater coil output from the stator. Pulser coil also shown alongside.

[99yam40]

I was just wanting to be sure he understood where he should try hooking up to the lighting coil wiring.
I do not thing it will be 12VDC going to the heater,
not sure but think it will be higher AC voltage.

do you have any info on voltage readings on the Valve heater coil and lighting coil at different RPM?

[boscoe99]

No voltages given for the Primestart heater coil.

[99yam40]

Without specs on the heater valve coil it would be hard to say if 60-75volts from the lighting coil would be a problem for the heater unit itself

[boscoe99]

Yep. Quite right.

[boscoe99]

I will look and see where else the PS is used. Might be powered by a lighting cool on another model.

[99yam40]

His model does not show up here being not from USA, so hard to see what the part number is.
but seems the heater unit( Starter) shown here for USA models on carbs from 94 on up look to be the same.

maybe when they started producing more output from the lighting coils that had to create a different coil just to run the heater unit to limit what was fed into it

[Stevie774]

Good morning, I was wondering if you managed a fix for the primestart problem, I too also have a motor with the same problem
TIA

[cleddau1]

Sorry for (very) late reply. I removed the flywheel and checked all the circuits on the stator coils for continuity and all ok. Cleaned all connections especially the earths (ground). The Primestart device now works in that it gets warm when the engine is running. I tested the Primestart device with 12v and the needle moves about 5mm which is OK. However the motor is still running rich. It starts easily but plugs get sooty and lots of soot appears in the exhaust cooling water. Adjustment of the mixture screw makes little difference. Compression is 147-149 psi both cylinders.

[99yam40]

just for the heck of it check the prime start system by turning the red lever to off after the motor has warmed up to see if that stops the over rich problem

[cleddau1]

No red lever on this Primestart.
Wondering if the jet the Primestart needle fits into needs replacing.