Plugs stop sparking at the tip?

[Farmingstock]

Got an old atv, when I put a new plug in it it started and ran well, however after 5 minutes it stopped running and wouldn’t start again!

I checked to see if it had spark by putting the plug next to the head and it sparked but only in the centre of the plug not at the tip, tried to clean it but it wouldn’t change!

I found an old plug cleaned that up and it sparked at the tip as it should, put tgat in the bike and it fired up straight away, however 5 minutes later the same thing happened again?

I haven’t got another plug as yet as need to order one but is there anything that could be causing this to happen?

The plug isn’t wet when it comes out!

[Nobby the Bastard]

Coil is breaking down and fails when it gets hot. Once it cools it starts working again.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Farmingstock]

It’s still the same when it’s cooled, I wouldn’t say it’s bearly warm, I can touch the exhaust without burning hand!

[Nobby the Bastard]

You said changing the plug (which takes time so the coil will cool a bit) fixed the problem temporarily.

Therefore it's not the plug. The coil may have now gone terminal.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Farmingstock]

I tried another brand new plug I had, wouldn’t fit as it was too thick but sparked perfectly when trying that, even checking now completely cold the plugs that were in both have bad spark but the new one is perfectly fine with no arcing!

[Nobby the Bastard]

It's the coil.

Either believe me or don't believe me. A new spark plug of the right size will cost about £3.

If it still has the same symptom with a new plug you will realise that I'm right.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[blurredman]

If the coil is hotter than simply warm, then that is a big identier to the coil breaking down... How warm is it?
____________________
CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S.
Current: 1973 MZ ES250/2 - 17k. , 1979 Suzuki TS185ER - 9k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 38k, 1989 MZ ETZ251 - 49k

[Farmingstock]

Not sure you understand what I wrote, so I’ll try and explain again and dumb it down as best I can!

1, I have ordered a new plug but have to wait as not in stock!

2, both plugs I used don’t spark properly when held next to the cylinder head (using the traditional plug test method)

3, when trying a brand new plug within seconds of trying the other 2, it sparks fine! This BRAND NEW plug, THAT SPARKS FINE, has threads to big to fit in the barrel, hence can’t use it!!!

4, again I have ordered a new plug that will fit!

5, again when using the new plug it sparks fine, UNLIKE the other two that don’t spark fine!

6, new plug spark fine, old plugs not spark fine!

7, if your telling me that the coil is faulty even though the new plug sparks fine but the old plugs don’t then it doesn’t make any sense at all!

[Farmingstock]

Ha ha ha who said the coil is warm??

[Nobby the Bastard]

It doesn't get away from your symptoms of it stopping after 5 minutes but once it's given 5 minutes it starts again with the same plug and you have tried 2 plugs which both showed the same symptoms.

How about I suggest that it's fucking aliens causing it rather than the obvious solution that the coil is getting hot and failing which is a known thing?
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Pete.]

Could be a very rich mixture especially if it's coupled with low compression where oil is getting past the rings and washed up into the plug. The engine will start when it's cold because it needs the extra fuel but after that it's just flooding the engine. Lawn mowers are prone for it.

Try a hotter grade of plug.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Farmingstock]

Nobby

Don’t know if your just being awkward or daft!

I’ve obviously explained, the coil isn’t getting hot? I don’t know where you got that from?

I obviously explained I’ve tried different plugs instantly, the new one works old one doesn’t?

Are you only reading things you want to read or just a keyboard warrior??? Can you read what I am posting??


Pete.

It does start fine from cold with a decent plug in it but I will order a hotter plug like you suggest, it’s a 200cc Honda ATV 4 stroke, I’ve checked valve lash etc has a DR8ES-L in It, they don’t do a DR9ES-L any suggestions?

[Pete.]

[Nobby the Bastard]

Not sure how fitting a hotter plug would fix rich mixture, low compression and oil getting into the cylinder but if you must...


It wouldn't fix a.knackered.coil either.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Pete.]

[Nobby the Bastard]

Good point. No mention on the colour of the plug though.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Farmingstock]

Brand new plug that had been in 2 minutes!

[P.]

[Nobby the Bastard]

Why not mention that the plugs were getting completely fouled up in the first place?
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Farmingstock]

[Nobby the Bastard]

Don't give allnthe symptoms, get a wrong diagnosis.
Its not like it's a minor symptom either. That that is so far beyond the normal definition of fouled up its scarcely believable that an engine even did this.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Farmingstock]

[Pete.]

Massive over-fuelling. Either the choke is stuck on or a jet has fallen out in the carb or the needle is not being held in place by the clip.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Farmingstock]

[Pete.]

That's the emulsion tube, it should have the main jet scewed in the hex end and the needle pokes into the other.

Never seen one bent but if you say so...
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good