Hi all,
Craftsman lawn mower with Briggs Stratton Engine model 110P 02 0003 F4, 175cc OHV, 7.25lbs-ft torque, 3 years old. Engine will not start at all or starts but stalls in a second or two. And can't restart it after that. I removed the spark plug and it was wet with fuel. I cleaned it and dried it. I reinstalled the spark plug but I didn't connect the ignition wire to the spark plug. Instead I had my friend holding the ignition end approx 1/2 inch away from the spark plug itself. Pulled the cord and the engine started fine and kept running as long as the ignition wire was maintained at approx 1/2 inch from the spark plug. So I then connected the wire to the spark plug as it should be. Pulled the cord a few times but wouldn't start (or barely putters and dies in 2 seconds). I'm confused....:frown:... Can anyone help?
Thanks.
Mike
This is the "old school" fouled plug test.
Voltage accumulates at the end of the spark plug till there is enough potential to jump the 1/2" gap
Because the 1/2 " gap is a very high resistance when the voltage gets to the spark plug gap it will jump it regardless of weather there is a lower resistance path to ground ( fouled plug, cracked insulator etc, etc, etc)
IT has been around from the beginning of time and all of those magic mileage boosters, fuel economizers , spark intensifiers all worked on this system, which by the way overheats the coil and causes it to fail prematurely but long enough in the future for the idiot who installed them , not to blame the miracle box they paid a fortune for.
So yes your plug is dead, gone to the big engine in the sky, no longer of this earth , deceased , kaput , faulty.
Modern standard spark plugs are a loss making item, the plug companies break even at best making them so they don't give a wrinkled rats rectum about them.
They want you to have problems with them so you will be encouraged to fit one of their you beaut platimum plugs which they make a healthy profit on.
Mower engine makers will of course not fit a $ 10.00 plug when they can get away with a 50¢ spark plug because that $ 9.50 can be the difference between a 200,000 engine order and laying 50 people off an assembly line.
Even worse, exhaust gas analysers have gotten a lot better and lead is the DEVILS own metal so any lead in the exhaust will cause life on the planet to expire.
The porelean insulator has a lead glaze on it to prevent build up so a lot of makers no longer glaze the insulators hence they will hold contamination a lot better than the old plugs.
Then you have the fact that modern "FUEL" is not petrol it is a mix of refinery waste fluids & by products. Into this they toss some aromatics ( stuff that evaporates to a gas at room temperature or lower ) so the engine can start when cold .
So if a brand new plug fails to fire in the first few revolutions this "fuel" coats the unglazed insulators and provided a conducting route to ground so the plug will then not fire unless burned off.
This is the "bad in the box" syndrome you will see all over the web uploaded by idiots with 1% higher IQ than a monkey who want to believe that the entire planet is against them rather than admit they are fools.
And because it is always easier to believe in a conspiracy rather than do the hard thinking and find out the truth, the "bad in the box" conspiracy stories abound.
Every single spark plug is tested several times before it gets the name printed on it then packed into boxes or bubble packs.
