to30 weak spark

[barry318]

I have just installed a petronis electronic ignition, mainly because I was tired of messing with points & a weak spark condition which I"m assuming is causing my no start condition. Still have weak spark & still not starting. It"s 6 volt positive ground has new copper core wires, new plugs, new ignition switch. Pull coil wire out of cap & get a very weak white spark. Any suggestions before I through more parts at it? Would anything other than coil cause this? Coil was replaced a couple of years ago and has 3 ohms across neg & pos terminals, but I"m wondering if this is problem.

 

[Anonymous-0]

Barry
Are all of your electrical connections clean and tight ?
Did this just start giving you a problem lately ?
Did you replace the coil wire when you replaced the other wires ?
Are wires at the ignition switch clean and tight ?
Are any of the wires in the ignition circuit bare and going to ground ?
Good luck

 

[Jerry/MT]

You have a 12v coil on a six volt system. A six volt coil will have about 1.6 ohms resistance.

 

[barry318]

coil has printed on it 6 volt no resistor required

 

[barry318]

I've been fighting this for quite a while. Usually starts ( unless its very cold out ) but have to keep choke partially out. all wires except one from v-reg new & tight. coil wire was replaced & even tried another one. will check that & all other wires. doesn't even try to start even with a shot of ether

 

[barry318]

I've been fighting this for quite a while. Usually starts ( unless its very cold out ) but have to keep choke partially out. all wires except one from v-reg new & tight. coil wire was replaced & even tried another one. will check that & all other wires. doesn't even try to start even with a shot of ether

 

[Jerry/MT]

If it has 3 ohms of resistance as you say it"s not a 6V coil. 6V coils run at 1.6 ohms and true 12V coils(i.e. coils for use with 12V systems without the requirement for an external resisitor) run at 3.25 ohms. With 3 ohms resistance, your primary current is around 2 amps and it should be closer to 4 amp max.

 

[gshadel]

I agree with Jerry, you coil should be drawing 1.5 ohms, not 3 ohms. You need a new coil. Your coil is either faulty or mislabeled. Also, polarity on the coil matters, the terminal with the small (+) sign on it should feed your distributor on a 6V pos. ground system. As the other guys pointed out also, make sure your wiring from your battery to the coil and distributor is clean and shiny. 6V systems are intolerant of corrosion. With just the ignition ON, check the voltage to the coil, should be 6V. New ignition switches are known to sometimes be bad, so are V. Regulators. All made in Asia.

George

 

[barry318]

Coil was hooked up that way when points were in it, but with the Petronis igniter instructions say + terminal on coil goes to + battery or ground & - terminal goes to igniter. I replaced ALL wiring & cleaned all terminals yesterday. I bypassed ign. switch as recomended by Petronis - still no start but sounded like it was trying to fire. Any recomendations on what coil to use? Petronis says I need a minumum 1.5 ohms resistance or greater. Battery shows 6.6 volts but I have to recharge it after trying to start as it starts to run down. I'm out of work but need to cut fields so I'm tight on funds. Would you recomend coil or battery replacement first? Many thanks to all respondees.

 

[barry318]

Any recomendation on what coil to use? NAPA # IC7 ? I'd like to purchase a coil locally so I can check resistance before buying it. Many thanks for all help!

 

[Bob (Aust)]

It"s 6 volt positive ground

...but with the Petronix igniter instructions say + terminal on coil goes to + battery or ground & - terminal goes to igniter.

Re read the Petronas instructions carefully as that configuration - or what you appear to be suggesting - will not work. What you've written would result in both sides of the coil at positive or ground potential and you'd have no spark.

Are you sure the Petronix unit is for 6 volt, positive (+) ground ignition system?

If it is a 6 volt, positive ground Petronix unit:
[list:729aa39870]* The battery positive (+) is connected to ground via the tractor frame;
* The battery negative (-) is connected to the ignition switch;
* The positive (+) side of the coil will go to the distributor and Igniter unit; and
* The negative (-) side of the coil will go to the ignition switch.[/list:u:729aa39870]
The distributor points (or Igniter unit) always switches on the ground or earth side of the coil. Go to the FENA site and study [b:729aa39870]THIS[/b:729aa39870] wiring diagram.

And take great care - if you reverse polarity on a Petronix Igniter you are likely to fry the unit.

I have two Petronix Igniter units, in my 1953 TEA20 Ferguson tractor and my 1966 XKE Jaguar. I am very happy with both units.

Bob in Oz
'53 TEA20

 

[Jerry/MT]

I don"t know the part number for the NAPA 6V coil but they can find one for you.

 

[Anonymous-0]

You have to be sure of what you have . Is your tractor pos. or neg gnd . ? The petronix units are good units , but , they can be had either pos. gnd. , or neg . grnd. . They are not protected if hooked up backwards .
You have to be sure that you and the petronix rep are on the same page .