Petrol engine spark testing trick

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Petrol engine spark testing trick Nov 19, 2019 16:04:07 GMT via mobile phil70 and Jim like this

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Post by Deleted on Nov 19, 2019 16:04:07 GMT

I was given a nice Yamaha Malta outboard a while ago but it stopped working. Took the carb apart to find the float needle was sticking. Nothing too serious then. Now running fine. During my idle perusings of ybw forums someone suggested spraying fuel into the air intake as a simpler way to check the spark than taking the plug out.

So I put some 50:1 in a kitchen cleaner sprayer injected it into the air intake while pulling the starter. And it worked lovely !

Probably an old trick everyone knows about anyway but in future it's the first thing I will try with a petrol engine which doesn't want to start. Gets the ignition question answered in half a second.

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Petrol engine spark testing trick Nov 19, 2019 23:16:22 GMT

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Post by Deleted on Nov 19, 2019 23:16:22 GMT

I always thought of that as another test for fuel starvation. But if the motor keeps going then I suppose its fairly conclusive proof of a spark too. I'd still reach for the plug wrench first though. Incidentally, a shot of WD40 often has the same effect in a reluctant motor.

samsam Member Posts: 229	Petrol engine spark testing trick Nov 20, 2019 0:47:07 GMT Quote Select Post Deselect Post Link to Post Back to Top Post by samsam on Nov 20, 2019 0:47:07 GMT Acetone, brilliant.
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Jim Super Member I'm a handsome gutless invertebrate. Posts: 15,896	Petrol engine spark testing trick Nov 21, 2019 16:35:17 GMT via mobile naughtyfox likes this Quote Select Post Deselect Post Link to Post Back to Top Post by Jim on Nov 21, 2019 16:35:17 GMT I'd prefer to pop the plug out too, it can tell you a bit about the mixture setting, is it oiled up etc. Then test for spark, earthed against engine.
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naughtyfox
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Petrol engine spark testing trick Nov 21, 2019 16:39:50 GMT

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Post by naughtyfox on Nov 21, 2019 16:39:50 GMT

Nov 21, 2019 16:35:17 GMT Jim said:

I'd prefer to pop the plug out too, it can tell you a bit about the mixture setting, is it oiled up etc. Then test for spark, earthed against engine.

Yes. Why would one not take the spark plug out for a lookey-lookey?

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I hope that I never become famous and someone trawls my contributions on this site looking for the odd post which may be offensive.

Force them to pluralise words by putting apostrophes in, then everyone will mock them as imbeciles!

Deleted Deleted Member Posts: 0	Petrol engine spark testing trick Nov 21, 2019 16:40:51 GMT via mobile Quote Select Post Deselect Post Link to Post Back to Top Post by Deleted on Nov 21, 2019 16:40:51 GMT Idiot.

Deleted Deleted Member Posts: 0	Petrol engine spark testing trick Nov 21, 2019 16:49:53 GMT via mobile naughtyfox likes this Quote Select Post Deselect Post Link to Post Back to Top Post by Deleted on Nov 21, 2019 16:49:53 GMT Man who eats crackers in bed wakes up feeling crummy.

Deleted Deleted Member Posts: 0	Petrol engine spark testing trick Nov 21, 2019 16:52:35 GMT via mobile Quote Select Post Deselect Post Link to Post Back to Top Post by Deleted on Nov 21, 2019 16:52:35 GMT Man who argues with wife all day gets no piece at night.

Deleted Deleted Member Posts: 0	Petrol engine spark testing trick Nov 21, 2019 16:55:58 GMT via mobile Quote Select Post Deselect Post Link to Post Back to Top Post by Deleted on Nov 21, 2019 16:55:58 GMT Agreed

naughtyfox Super Member BUSY KILLING CHICKENS! Posts: 36,429	Petrol engine spark testing trick Nov 21, 2019 16:59:34 GMT Quote Select Post Deselect Post Link to Post Back to Top Post by naughtyfox on Nov 21, 2019 16:59:34 GMT Nov 21, 2019 16:40:51 GMT @someboater said: Idiot. Greta.
	Quiet minds cannot be perplexed or frightened but go on in fortune or misfortune at their own private pace, like a clock during a thunderstorm. I hope that I never become famous and someone trawls my contributions on this site looking for the odd post which may be offensive. Force them to pluralise words by putting apostrophes in, then everyone will mock them as imbeciles!

naughtyfox Super Member BUSY KILLING CHICKENS! Posts: 36,429	Petrol engine spark testing trick Nov 21, 2019 17:01:24 GMT Jim likes this Quote Select Post Deselect Post Link to Post Back to Top Post by naughtyfox on Nov 21, 2019 17:01:24 GMT Nov 21, 2019 16:44:48 GMT @bellenda said: Proverbs 15:14 The heart of him that hath understanding gets added to lambs lungs and liver to make haggis: but the mouth of fools feedeth on McDonald's Fillet O'Fish.
	Quiet minds cannot be perplexed or frightened but go on in fortune or misfortune at their own private pace, like a clock during a thunderstorm. I hope that I never become famous and someone trawls my contributions on this site looking for the odd post which may be offensive. Force them to pluralise words by putting apostrophes in, then everyone will mock them as imbeciles!