Old Yamaha 3.5hp advice required

[TomKat]

got my ebay special last week and have been stumped by not being able to get a spark.

Points are clean and gap looks OK.

There are two wires coming out one black and one white, I assume the black is a kill switch. any ideas on what the white one is? should it be earthed.

Continuity test of the coil looks OK in that its not a dead short or open circuit.

Any pointers? Loosing interest rapidly!

[9D280]

Absolutely no spark might hint it is earthed where it shouldnlt be? Or if it's points type ignition is the condenser gubbed?

How old is it? I have a 1970s (designed in the 60s) Johnson that rather than shorting the ignition to stop just retards the spark so far that it fires during the exhaust stroke! Might it be something like that?

[m chappelow]

Originally Posted by TomKat

got my ebay special last week and have been stumped by not being able to get a spark.

Points are clean and gap looks OK.

There are two wires coming out one black and one white, I assume the black is a kill switch. any ideas on what the white one is? should it be earthed.

Continuity test of the coil looks OK in that its not a dead short or open circuit.

Any pointers? Loosing interest rapidly!

Recon it's condenser too ,there either working or not,though have had some intermittent working ones
Not often it shows with flywheel mags but sometimes the points go black that's a good indication the condensers not happy.

Could even be the plug cap or lead sometimes the spike that makes contact with the lead can get corrosion at the end

[TomKat]

thnaks chaps, will get a night this week and see what I can figure out, most likely the condensor as you say, points look a bit black.

[TomKat]

Would quite like to try a new condensor, any idea on where to get one in the UK? all I can find is this one from the Netherlands (with a .co.uk web address rather bizarely!)

Yamaha outboardmotor Condenser 3.5A, P95, 5A, 5B [654-81325-20] - €23.25 : Yamaha Outboard Parts, Boats Parts Yamaha Outboard Klijzing

[m chappelow]

Originally Posted by TomKat

Would quite like to try a new condensor, any idea on where to get one in the UK? all I can find is this one from the Netherlands (with a .co.uk web address rather bizarely!)

Yamaha outboardmotor Condenser 3.5A, P95, 5A, 5B [654-81325-20] - €23.25 : Yamaha Outboard Parts, Boats Parts Yamaha Outboard Klijzing

Most condensers are the same inside just the size
Try a motorcycle or car accessory shop first
I have some in a box somewhere if I can find them you can have one .

[TomKat]

on further investigation today (wet day!!) I have pulled the coil out and it appears to be gone, it is a coil directly connected to the pug via HT lead. Sticking the meter between the coil feed with and plug end of the HT lead is open circuit. Condensor may have gone as well.

Anybody got a spare coil, not sure its worth spending any money on but it would be nice to bring it back from the dead!