Forum

[Nettshubby]

he does say it has fresh fuel.

[jefrs]

Bantams have to be well shaken before use! - because the oil sinks to the bottom of the tank, clogs the filter in the tank (I removed it) , goes down the pipe and then clogs the filter in the banjo bolt before filling the float bowl and won't go through the jet. This became the "Bantam dance" every morning nevermind six months.

[jefrs]

Sparks are 10,000 volts per centimetre in dry air. We don't have 'dry air' in the engine and the compression 6.5: or 8.5:1 whatever, reduces the distance it will jump. Spark colour is ionisation, a rough indicator of current discharged. You might get sodium from road salt but I hope we're talking with clean plugs here. It's just an indicator that you do have a spark and you do get used to judging whether it's a good spark or not. A poor spark could also be condenser but you have a Boyer. Don't hold the spark plug in your hand when you try it, it's not something you forget

I'm scratching my head here trying to think why it won't go if you have spark and petrol. Have you just fitted the Boyer? - check the wiring etc etc. It "broke down some time ago", what was the problem and does it have some bearing on why it won't go like an old Ford ("won't go, won't go, won't go") now. You have new petrol but how long was the carb sitting in old stuff; maybe time to strip the carb out.

[Bullet Whisperer]

Unlikely, but here goes - I once had my 350 Bullet splutter to a halt. It would fire occasionally when I tried to start it and even try to idle now and then, but would not run. It turned out the needle clip in the carb had failed and the needle had dropped down through the slide - worth a look, maybe? Regards, Paul.

[PeteF]

Jefrs, there is often enough sodium in the atmosphere to cause the orange ionisation. Don't take my word for it, I refer you to Briggs and Stratton (who possibly know a thing or two about engines)

[jefrs]

I've had several lawnmowers and I've come to the conclusion Briggs & Stratton don't make spark plugs. It there was a lot of sodium in the air everything would burn with a Na-yellow flame. Characteristic D-line of sodium is yellow, which is why sodium street lamps are yellow, throw some NaCl salt into the fire etc. Ionisation colour is like heating metal, goes up from dull-red to blue-white, same reason - excited electrons emitting photons with more energy (colour) as they fall back to base state, increase the energy beyond visible and we get x-rays (we're photons too).

The electrode may colour the spark, they use various alloys, copper, yttrium, platinum, itrrridium, phos-bronze and steel &c.. Iron gives us red, copper green. Also crap on the plug. I'm not saying you can't have sodium present but it's not what to look for and if you don't live at the seaside it shouldn't produce a false test reading.



It's just an visual indicator - if you have a big fat spark you have more whumph than a thin weedy one. It really doesn't need the HT probe on the oscilloscope

[Beezabryan]

He knows your know

[Dennis C]

That sounds just like Hilda Baker talking about Ely.

[Beezabryan]

peed ant mode on - it's Eli innit - peed ant mode off

[PeteF]

I, however, did live very close to the sea for many years and always puzzled over the fact that I could never get the blue spark that everyone said I should get. When there's a nor-easter blowing there is so much salt in the air you can taste it. Certainly enough in the air to ionize in a spark.
So I repeat, don't ditch a plug just 'cos you can't get a blue spark.
No, B&S don't make plugs but they did do a lot of development in solid state flywheel ignition modules so I'm assuming they know a bit about HT systems.