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On 24 May 2011, Spark plug was mentioned from xkcd, a high-traffic website. (Traffic) All prior and subsequent edits to the article are noted in its revision history.

It is missing some commons problems such as Spark plug well filled with oil Schengen2018 (talk) 14:54, 11 October 2019 (UTC) https://www.liveabout.com/spark-plug-wells-fill-with-oil-4083750[reply]

I've been trying to work out what a spark actually *is*, and how much current/voltage is necessary to produce one, and how long current must flow for to effectively ignite fuel+air mixtures... if there's an expert out there - could you perhaps add to this article?

What I *do* know is that different compressions and temperatures change the conditions. 203.206.137.129 20070510

A lot of that information was in the article "reading sparks plugs for racing" but that article was deleted for really lame reasons. You can still find it on wikibooks under the same title.--=Motorhead 22:14, 10 May 2007 (UTC)[reply]

See the bottom of this article (mainspace not talk) for a link to Wikibooks:Reading spark plugs for racing. Samw 03:15, 11 May 2007 (UTC)[reply]

The article could do with a mention of Paschen's Law and Secondary emission. Whilst I wouldn't want to make the article inaccessible, I came here to find out whether platinium, iridium, or ruthenium electrodes really make any difference to spark voltage, and whether alternative fuel mixtures require them because they are more difficult to spark; these are claims being made by spark plug manufacturers in their marketing material. My initial glance at these two WP articles suggested that the metal surface has no bearing on the breakdown voltage of the gas, but it does alter the number of electrons released when a +ve gas ion bangs into the cathode. Oh, where to find secondary references, though? JBel (talk) 08:45, 27 May 2019 (UTC)[reply]

Platinum-tipped plugs are as old as spark plugs. Certainly WWI aircraft were using them. It's not to do with the arcana of surface chemistry, it's just heat resistance. The hotter you allow a plug to run, the less trouble there is from oil (and other) deposits fouling it. Modern designs tend to have avoided this, by better control of insulator performance, by better cooling of cylinder heads (and so the spark plug body, as a heat sink for the insulator) and by better electrical design so that the spark is both more reliable (even if there's fouling) and yet less hot (no more of the old "blowtorch" plugs of the late '80s, trying to fire lean mixtures at high compressions by simply using ridiculous amounts of spark energy). Mostly though, modern oils, fuels and fuel injection management just don't foul plugs like they used to. Service intervals which were a 25k replacement a few decades ago are now 75k, with no cleaning and re-gapping needed inbetween. Andy Dingley (talk) 12:48, 27 May 2019 (UTC)[reply]

Would you consider a disc-type spark plug gapper to be simpler or more complicated than keys? (Well, it's clearly less accurate)

Both are about the same. The main thing would be to use the wrench to adjust the gap and not be tempted to pry it with the measuring tool.--=Motorhead 21:33, 1 Apr 2005 (UTC)

I've taken out the merge template with "spark gap" as these articles are distinct and do not significantly overlap, even if they use the same picture. --Wtshymanski 00:03, 10 Apr 2005 (UTC)

It is not true that the tapered seals of some Ford types without washers, need to be tightened to a much greater torque than the more common type (flat with washers). The required torque is generally less, and it is much more critical that they not be overtightened.

I have the Haynes service manuals for the Fiesta Mark 3 (1989 to 1995), which states the required torques for the HCS and Zetec (which had tapered seat plugs), and the CVH and PTE types of engine (which I gather did not). The recommended torque settings for the HCS and Zetec are less than for the other two.

In addition the recommended spark plug torque settings for the first type of Nissan Micra (1983 to Jan 1993), which has plugs with washers, is significantly higher than that for an HCS Fiesta (with tapered seat plugs).

I have had both sorts of vehicle. On my first Fiesta, (late 1989), I had to take three of the plugs out quite frequently and either clean or replace them, because they fouled up due to the engine burning oil. I always used a torque wrench to install them, and also used a smear of copper grease as an anti-seize compound (which the Haynes manual also suggests).

(I live in Britain, by the way.) Roo60 23:58, 29 October 2005 (UTC)[reply]

P.S. Please see http://www.honestjohn.co.uk and look under Car-by-Car Breakdown, for the Ford Fiesta (1989-1995) and the Ford Ka. Roo60 00:54, 30 October 2005 (UTC)[reply]

I have never heard this used in Britain; indeed, it simply sounds archaic. I am thus removing it. --^pirate 13:54, 25 March 2006 (UTC)[reply]

See The Bosch book of the Motor Car, Its evolution and engineering development, St. Martin's Press, copyright 1975, Library of Congress # 75-39516, pp 206-207.

Also see 24,400 Google hits. ;-)

Atlant 14:59, 25 March 2006 (UTC)[reply]

I recall seeing this term in older British publications, probably from the 1940s/1950s. Incidentally, I loved the old Brit term for cleaning two stroke heads and ports: decoking. LorenzoB 22:30, 12 November 2006 (UTC)[reply]

"Sparking plug" was the usual term in Britain in the 1950s. Biscuittin (talk) 11:01, 27 October 2011 (UTC)[reply]

Should definitely be removed then if the usage is as ancient as described above. — Preceding unsigned comment added by 77.97.62.13 (talk) 02:39, 6 January 2012 (UTC)[reply]

I found this like via Fark.com [1] The first line reads:

Scientists have devised a way to replace spark plugs with laser beams to reduce fuel consumption and emissions.

Also I have heard from a mechanic friend of mine that ford or someone has created an engine without spark plugs using insted a tessla coil like device. --Doom Child 04:13, 16 April 2006 (UTC)[reply]

The first spark plug is widely attributed to Edmond Berger who did not patent his invention. More specifically the invention is dated to February 2, 1839. --Nick 3216 13:31, 9 August 2006 (UTC)[reply]

Where is this “widely attributed”? The reference for Berger inventing the first spark plug only states he did so, but doesn’t provide any evidence to prove it.

Do you have anything that would show he did create the first spark plug? Can you even prove Edmond Berger existed, because I certainly can’t.—UselessPistol (talk) 23:30, 12 April 2023 (UTC)[reply]

This is incorrect - diesel engines inject diesel into heated compressed air - otherwise they would suffer detonation. This should be amended

You are correct. Feel free to amend articles as you see fit. If its not accepted it will be changed then you can argue it out with whoever.--=Motorhead 16:04, 30 September 2006 (UTC)[reply]

Misses due to excess plug gap will show up at idle, not at high speed. At high power output the temperatures, pressures and fuel/air densities are high enough to *almost* ignite on their own ( ie detonation ). The toughest situation for an ignition system is idle, in other words idle requires the highest voltage to ignite the mixture.
Back in the day there was such a thing as high speed misses( 30+ years ago ), but this was caused by the points in the distributor bouncing .
As for a wider gap producing a hotter spark... this is irrelevant as any spark is "hot" enough to ignite a proper mixture.
SatnSpwn (talk) 00:58, 18 November 2007 (UTC)[reply]

I didn't see this mentioned in the main article, so if it is than please just disregard.

An evolution of the "hotter = better combustion" philosophy, Honda has started equipping its new cars with dual probe spark plugs. The spark gap now separates an iridium probe and a platinum probe, supposedly producing a hotter spark. I believe the idea is to increase the intensity of the spark rather than the quantity of them. Generally, OEM means a legitimate technology so I figured this deserved a mention.

Links: [2], [3]

LostCause (talk) 20:43, 5 February 2008 (UTC)[reply]

When you try to click on the link to the Dutch version of the page the browser tries to download the page rather than surf to it. —Preceding unsigned comment added by 80.79.40.9 (talk) 19:34, 21 September 2008 (UTC)[reply]

Second line says a spark plug "ignites compressed aerosol gasoline". Is aerosol correct? I have always believed (as a petroleum refinery engineer) that the gasoline is vaporized (not aerosoled) in the carb and intake manifold. Thus the fuel air mixture in the cylinder is all in gas phase.

Perhaps it could say: "...a spark plug ignites fuel atomized by the injector or carburetor.". It might be a good time to mention that this is the beginning of the power stroke.1Engine (talk) 16:23, 11 May 2014 (UTC)[reply]

To vaporize, the gasoline must absorb heat from the engine. That is why a cold engine has trouble starting (without choke).

Am I wrong?---- —Preceding unsigned comment added by 66.27.79.138 (talk) 21:36, 3 January 2009 (UTC)[reply]

It's both - partially vapourized (gaseous), but also largely an aerosol (fine droplets of liquid). Obviously a cold inlet charge will tend to shift the equilibrium more towards aerosols, which are equally obviously more difficult to ignite.

As for which is delivered, then early cars (very low specific power outputs) began with "wick" and similar carbs, which work purely by vaporization (and not very well!). Modern cars use fuel injection which works solely by atomization as an aerosol, then by boil-off to vapour from the surface of these droplets. A carb of the '60s would use both, vaporizing efficiently over the efficient cruising range, then moving to a more atomized flow at their performance limits - one of the reasons why their efficiency dropped so badly when worked at full power, especially when under-carburated.

For vaporizing an aerosol, then the heat (in an efficient design) is mostly supplied by adiabatic compression during the compression stroke. Although "hot spot" manifolds and the like have been used ('40s tech) and they do indeed improve cold-starting of low compression engines, they're horribly inefficient in general service. A modern car (high compression, good piston ring sealing from cold, powerful electrics for rapid cranking when cold) will simply cold-start quickly and easily, compared to how things were 20 years ago. It also needs far less mixture enrichment to do so, although the provision of pre-heated inlet air is taken far more seriously nowadays. The warmth of "the engine" (meaning mostly block, coolant & lubricant) has relatively little to do with it. Andy Dingley (talk) 22:50, 3 January 2009 (UTC)[reply]

This diagram (310px-Plug_construction.jpg) is HORRIBLE. Unencyclopaedic!! Does not even show many of the details it should! http://upload.wikimedia.org/wikipedia/en/thumb/9/90/Plug_construction.jpg/310px-Plug_construction.jpg

There are better ones in the commons.

I'll put one in if no one else does first. NOTE the WikiCommons ones may need translation to English. (from French or German I think)

--220.101.28.25 (talk) 00:22, 29 October 2009 (UTC)[reply]

Hey Motorhead, if you see this I hope you weren't offended by my comments on your diagram. Would you like to improve it?

If possible, I would really like to use something like this one http://commons.wikimedia.org/wiki/File:Bougie_coupe.jpg

--220.101.28.25 (talk) 01:53, 29 October 2009 (UTC)[reply]

Actually that was a photocopy of a photocopy of a hand drawn sketch I did 30 years ago. I scanned the whole document with all its sketches and used it as a starting point for a "reading spark plugs" article that is no longer here, it was pushed into wikibooks. It was intended only to show the general internal structure in order to cut apart the spark plug for reading purposes. I intended to replace it but lost interest when it was moved to wikibooks. I dont recall how it got onto this page. Anyhow it can stand replacement if you have one. The one you suggest looks to me like a commercial one with french add on labels.--=Motorhead (talk) 01:58, 30 October 2009 (UTC)[reply]

Wanted to include this in the article BUT,

Can't find anything current for the use of lasers instead of spark plugs. Latest internet info seem to be mid 2006.

Sounds feasible though --220.101.28.25 (talk) 05:37, 29 October 2009 (UTC)[reply]

There was a Doowop band in the 50's called Spark Plugs, and all I know about them is they had an LP called "Crazy Beat with the Spark Plugs" recorded by a rare studio called Sutton. It is amazing, but there is nothing on the internet except a video on Youtube with a song and the original vinyl photos. I really thought there was some info in Wikipedia but there is not. —Preceding unsigned comment added by Miguelaccp (talk • contribs) 15:18, 31 December 2009 (UTC)[reply]

JosephJohnT (talk) 04:22, 25 April 2010 (UTC)==pop Culture==[reply]

Artist Joseph John Trukovich paid homage to the "Champion" Spark Plug with a Sculpture/Painting. http://www.flickr.com/photos/josephtrukovich/4030526599/in/set-72157600312719106/

It's looking a bit full in there. What's justified and what should go? Do they meet WP:EL, pass WP:ELNO or do they not? Andy Dingley (talk) 11:59, 8 October 2010 (UTC)[reply]

First up:

• Fault Diagnosis gsparkplug.com

Added twice this week, it's the classic "diagnosis by nose colour" photo gallery.

I've reverted it once this week, but would have to admit that it's better than a "revert on sight" link, so I'm raising it here.

• Spark Plug Colors, and What They Mean 4x4review.com

Very similar to gsparkplug.com. We only need one, so which one (or another) stays?

• Common spark plug conditions opc.mr2oc.com

Another plug colour gallery

• Ford To Replace Spark Plugs With Freakin' Lasers by 2011

Might have once been acceptable as a supporting ref to article body content re laser ignition, except that: It's stale. Especially when claiming 2011, we'd want to see newer and more detailed news by now. Secondly it's not credible, by 2011 at least. Thirdly Ford are fond of publicity, but they're not an innovative company in combustion technology. Anyone remember their lean burn debacle? (I could say more, but then they'd probably have to kill me).

• Elements used in spark plug construction

Nice site, and again it might make a supporting ref for radioactive sparkplugs, but it doesn't really add stand-alone content the way WP:EL needs to.

• Common Spark Plug Sizes

If there's any useful WP:EL content here, it's hidden behind an advert for wrenches.

• Video: How to change plugs

WP:NOTHOWTO would seem to apply.

IMHO none of them belong here - and I've removed the gsparkplug.com link several times from this and other articles. --Biker Biker (talk) 17:22, 8 October 2010 (UTC)[reply]

I can just about justify one, and only one, colour chart. Can't justify any of the others. Two days for discussion and then wipe as needed on Sunday evening? Of the colour charts, I'd favour gsparkplug.com as the best of the three. One is scanned bitmap text, not real text (possible Haynes copyvio too?) Andy Dingley (talk) 18:00, 8 October 2010 (UTC)[reply]

Does the comic strip reference really warrant an "In Popular Culture" section in the encyclopedia article on spark plugs? (My vote is "no.") Jtropp1 (talk) 19:28, 25 May 2011 (UTC)[reply]

No, per WP:XKCD. That's why the page is protected. OhNoitsJamie ^Talk 19:59, 25 May 2011 (UTC)[reply]

And that's exactly why I deleted it. No real discussion needed as it sounds like the three of us are in agreement. --Biker Biker (talk) 20:53, 25 May 2011 (UTC)[reply]

I find it interesting that Biker Biker removed the "In Popular Culture" section and citation and reference to xkcd when this Spark Plug article has already been flagged for not having a single citation or reference. Perhaps his time would be better spent adding citations and references to the existing artile than removing a harmless reference. — Preceding unsigned comment added by Bboorman (talk • contribs) 12:48, 26 May 2011 (UTC)[reply]

You are entitled to your opinion. Perhaps your time, after three years away from Wikipedia, would be better spent improving articles than adding trivia to them. --Biker Biker (talk) 13:06, 26 May 2011 (UTC)[reply]

How much electricity do spark plugs use? I really want to know and cant find any info on this! Tri400 (talk) 18:02, 7 August 2011 (UTC)[reply]

There are two ways to interpret this question. One is "How much energy is delivered into each spark?" and the other is "How much power is used in running the ignition system?"

Neither of these are dependent particularly on the spark plug. The plug delivers as much energy as is supplied to it. This depends on the energy stored, in either the magnetic flux through the coil or else a charged capacitor, which is then released through the plug. The overall consumption is usually dependent on the efficiency of the inverter driving the capacitor discharge unit - more energy is wasted (heat through the inverter transistors) than is delivered to the plug gap. As a rough figure (for this varies hugely) a 1980s transistorised capacitor discharge unit (with no computer ECU) would use between 50-100W. As to the energy delivered, then try estimating the charge available in a capacitor discharge unit from Q (in Joules) = CV and assuming that most (with some coil losses) is discharged to the plug gap when fired. Andy Dingley (talk) 10:25, 8 August 2011 (UTC)[reply]

3.1.4. and 3.1.7 are largely redundant, though one is a much longer cotton-mouthed version of the other. Industry shill (talk) 00:33, 9 September 2011 (UTC)[reply]

No, they're not redundant. I note that once again you've re-added the claim that spark plugs are sintered alumina throughout, a bad case of WP:RECENTISM at best and highly misleading in general. The insulator is in two parts, and has two functions@ the upper part is mostly an electrical insulator, the lower part is mostly a thermal insulator. There are probably modern plugs that manage to achieve both through one material, but for the vast history of the spark plug and its varied development, two different materials had to be used here, to achieve the performance needed. The upper insulator has almost universally been of glazed porcelain. The lower one is of sintered alumina, but stacked or rolled mica have an important history too. Andy Dingley (talk) 08:26, 9 September 2011 (UTC)[reply]

Sorry Andy, no offense intended. The insulator is one piece, not two. http://en.wikipedia.org/wiki/File:Spark_plug_insulator.jpeg Apart from the practical difficulty of spark leakage at junctions, two parts cost more than one. You can dissect a spark plug thus and check for yourself easily enough. Just grind off the sealing ring at the top of the hex head and it'll come apart, especially if the metal is warm.

There is also this diagram: http://bp2.blogger.com/_U8_oRrfOswQ/RvGXg-TMyQI/AAAAAAAAAAU/Vr_aww3TBes/s320/PlugDiagram.gif from http://dirtbikeblogger.blogspot.com/2007/09/what-spark-plug-does-spark-plug-has-one.html. I believe there's also an illustration and description in the Bosch Automotive Handbook, if you you're interested in dead tree format.

Industry shill (talk) 21:24, 9 September 2011 (UTC)[reply]

Congratulations. As noted, you've found a modern plug with a one piece insulator. Now take a look at Commons:Category:Spark plugs Andy Dingley (talk) 11:18, 12 September 2011 (UTC)[reply]

With respect, what you think you're seeing and what you're actually seeing are not the same. The only plugs in that ref that are not single pice sintered alumina are vintage - circa 1930 or older. Please read the Bosch Automotive Handbook reference or disassemble some plugs for yourself - as suggested earlier.

Industry shill (talk) 18:22, 17 September 2011 (UTC)[reply]

Two piece insulators are still commonplace. Andy Dingley (talk) 19:09, 17 September 2011 (UTC)[reply]

So you keep saying. Yet you're not reading the literature or bothering to actually dissect any plugs. Either are easy to do. Go ahead and do so and post your results. Industry shill (talk) 15:51, 18 September 2011 (UTC)[reply]

I agree with Andy. Just look at US patent 5204579, which features a spark plug that has to separate insulator pieces each made from a different material. --Biker Biker (talk) 19:40, 17 September 2011 (UTC)[reply]

Two things. 1. Companies file defensive patents. You can waste a lot of the competition's money hocussing them into researching methods that you will never actually employ yourself. 2. The patent refers to the use of aluminum nitride and silicon nitride. The cost associated with both those meterials, and their synthesis, is many orders of magnitude greater than the cheap and abundant material that is aluminum oxide. And neither are "porcelain".

Again, what you could do in manufacture and what you actually do are not the same. Patent filings are predominantly defensive and only a very small proportion actually protect active technologies. Industry shill (talk) 16:29, 18 September 2011 (UTC)[reply]

And who deleted the spark plug section diagram??? Deletionists suppressing unpalatable reality that conflicts with their lack of relevant technical knowledge?? Industry shill (talk) 16:37, 18 September 2011 (UTC)[reply]

I have no idea who deleted the first version, but I am nominating your new version for deletion. This isn't because of something that you have done, but because the original Polish language image has questionable credentials. I suspect that is exactly why the first version was deleted. Does that make me a deletionist suppressing unpalatable reality? --Biker Biker (talk) 08:31, 21 September 2011 (UTC)[reply]

What exactly are "questionable credentials"? Are they related to sour grapes?Industry shill (talk) 16:41, 21 September 2011 (UTC)[reply]

Biker Biker, I have changed the section diagram and given it English Labels. Hopefully this will now be agreeable. I have checked back with the Bosch Automotive Handbook, 8th edition. The description of the insulator construction on page 581 should answer any confusion between the shiny and non shiny appearances of different portions of the insulator which I think are causing this confusion. Industry shill (talk) 21:51, 20 September 2011 (UTC)[reply]

An image used in this article, File:Spark plug sd.jpg, has been nominated for deletion at Wikimedia Commons in the following category: Deletion requests September 2011 What should I do? Don't panic; a discussion will now take place over on Commons about whether to remove the file. This gives you an opportunity to contest the deletion, although please review Commons guidelines before doing so. If the image is non-free then you may need to upload it to Wikipedia (Commons does not allow fair use) If the image isn't freely licensed and there is no fair use rationale then it cannot be uploaded or used. This notification is provided by a Bot --CommonsNotificationBot (talk) 12:04, 28 September 2011 (UTC)[reply]

the Tesla patent quoted is not for a spark plug. This is obvious to anyone who reads it, but most Tesla fanboys just repeat the lies found on Tesla sites. Ion G Nemes (talk) 14:59, 30 September 2011 (UTC)[reply]

You are trolling right? Well, OK, I have bitten. Part of the Tesla patent, which a complete ignition system, very clearly shows a spark being discharged within the cylinder. So if it isn't a spark plug, what is it? --Biker Biker (talk) 15:51, 30 September 2011 (UTC)[reply]

Why do you keep deleting relevant information? You've deleted thread sizes - relevant. You've deleted a section diagram showing spark plug construction multiple times, and are attempting to do so yet again - relevant. Now you're trying to delete a very pertinent diagram showing the construction differences that determine a plug's heat range - relevant. I see your talk page littered with deletionist fragmenta, so this is clearly a vandalistic tendency you have. I'm not a Wikipedia expert, but I intend to look into whether your account can be nominated for freeze or even termination. You're a very destructive individual. Industry shill24.5.243.100 (talk) 19:46, 8 October 2011 (UTC)[reply]

You really don't get Wikipedia do you? You don't understand copyright. You don't understand consensus. You don't get on well with others. Yet, I'm the one in the wrong. How bizarre. --Biker Biker (talk) 21:47, 8 October 2011 (UTC)[reply]

Hmm, let's examine:

1. This page is woefully short on factual detail.

2. People attempting to introduce factual detail have their contributions deleted.

3. Multiple people all have their factual contributions deleted by one person - you.

As for "consensus", you are not the sole arbiter of that. As for "copyright", that is a red herring - all images are common media per Wikipedia guidelines. You need to get over yourself and stop this "censorship by technical allegation" crusade of yours.24.5.243.100 (talk) 22:51, 8 October 2011 (UTC)[reply]

A basic sizing chart so thread sizes could be viewed. Metric and SAE both need to be covered.

Example- I have an AC Delco plug in my hands- what is the thread size? SAE or Metric.

Not a comprehensive spark plug list- but a listing by company and what size is standard or main stream. thanks

Any discussion here would be so general as to be useless in identifying any particular spark plug; that's not the type of information to be collected here. Your best bet is a thread gauge or your vehicle manual. --Wtshymanski (talk) 14:42, 13 August 2012 (UTC)[reply]

No, this would be useful. Spark plugs only use a handful of standard threads, across brands. Also the relationship between thread size and spanner size isn't the standard one for bolts, it's specific to spark plugs. These threads have also changed over time, as engine developments required different sizes of plug. Andy Dingley (talk) 15:18, 13 August 2012 (UTC)[reply]

Great, so where can I find out more about the handful of standard sizes? Surely every company makes all the popular sizes, metric or inch? My Bosch handbook doesn't list them, but it's a pretty small book. --Wtshymanski (talk) 15:48, 13 August 2012 (UTC)[reply]

What colour is your Bosch handbook? I bet the maroon one does it, even if the blue one doesn't. Also it's axiomatic that everything is _in_ the Bosch handbook, but nothing can be _found_ in the Bosch handbook. Besides which, Bosch aren't the only game in town. NGK always used to have a really good technical catalogue on spark plugs etc. Andy Dingley (talk) 16:12, 13 August 2012 (UTC)[reply]

The little blue one - (Horst Bauer Bosch Automotive Handbook 4th Edition Robert Bosch GmbH, Stuttgart 1996 ISBN 0-8376-0333-1). A model of compact technical reference. I'll have to page through it when I get home. Do we have WP:RS issues with maker's catalogs? --Wtshymanski (talk) 16:25, 13 August 2012 (UTC)[reply]

This sounds like the perfect topic for a new Wikia spark plug spotters site, rather than an encyclopaedia. Sorry, but I just don't get why it would be of use here. --Biker Biker (talk) 16:29, 13 August 2012 (UTC)[reply]

I am trying to remove the spark plug from a generator, I wanted to quickly understand the likely sizes of tools, threads, etc. knowing nothing about the topic. Unusually I found Wikipedia was no help, and I soon became totally confused around metric vs. imperial, thread vs. hex. A simple note along the lines of 'spark plugs are typically either 18mm hex or 21mm hex (which may also be known as 10mm vs. 14mm thread, or 5/8 inches and 13/16 inches)' would have helped greatly. Manabroad (talk) 12:53, 27 December 2013 (UTC)[reply]

I believe that at one point, I tried putting into the article that a majority of plugs are either 5/8 or 13/16. What are the two most common nut sizes? Seems like a reasonable question that should be answered in the article. It was deleted. I think the editor said there was no reference to support the statement. Maybe submit the question to an auto mechanic columnist. When they answer the question, use that as the source. Or how about <ref>https://thehandynest.com/what-size-socket-for-spark-plugs/<ref>. "A spark plug commonly comes in 5/8 inches and 13/16 inches."

This is an encyclopaedia not an information bureaux. 86.130.28.61 (talk) 12:53, 9 October 2019 (UTC)[reply]

Spark plugs für motorcars were invented by German company Bosch. Inventor by Bosch was German engineer Gottlob Honold 188.96.181.140 (talk) 22:02, 7 May 2013 (UTC)[reply]

• "Spark plugs for motorcars" isn't a notable invention. "Spark plug" is, but they (and their use in stationary engines) pre-dates cars. These were invented and well-known before Bosch was involved.

Bosch made numerous inventions and developments to spark-ignition systems. However these were related to ignition magnetos, particularly the high-tension magneto (the type with a built-in transformer as well as being a generator). I am unaware of any inventions by Bosch (or Honold) that are specific enough to spark plugs to qualify as "the invention of the spark plug". There were many improvements to spark plugs, to make them more reliable and long-lasting, but even with these I don't know any by Bosch that would count to this extent.

I'd also note that Gottlob Honold is completely unreferenced, both here and at de:Gottlob Honold, although de: does have one deadlink published by Bosch themselves. Andy Dingley (talk) 22:37, 7 May 2013 (UTC)[reply]

This article does not even mention the process of INDUCTION that causes the emf of tens of thousands of volts.1Engine (talk) 16:31, 11 May 2014 (UTC)[reply]

No spark plug that I am aware contains anything remotely connected with induction. 86.130.28.61 (talk) 12:52, 9 October 2019 (UTC)[reply]

It took me one minute to find the answer to this Wikipedia tag "(questionable{{by who|date=December 2016}})" which had been inserted three years ago without action. I replaced the entire sentence with a new paragraph I found on the Polonuim page, that answered the tag, and showed that the claim in the removed section was not "questoinable" and thus the "by who" tag was indeed a correct tag. I wish the original editor, the one who inserted the "(questionable)" had done their research and either refrained from inserting it, or provided a reference.Nick Beeson (talk) 10:41, 4 October 2019 (UTC)[reply]

Drive-by IP from Optus in Oz. I've never seen a useful edit from that ISP.

The radium plug is the more notable here, as part of the whole "radium in everything" craze. Also polonium (even by radium standards) was always expensive and in short supply. It would be interesting to know the activity of these plugs, and how the polonium was sourced. Andy Dingley (talk) 11:00, 4 October 2019 (UTC)[reply]

BTW - [4] too. Andy Dingley (talk) 11:05, 4 October 2019 (UTC)[reply]

Intersting that your linked source states that the radioactive material was polonium-210 and then goes on to state that a Geiger counter failed to detect any residual radiation today. In fact a Geiger counter would not have detected any radiation when the plug was new, because polonium-210 is solely an alpha particle emitter which a Geiger counter cannot detect.

Polonium cannot have been in that short supply as it was supplied in large numbers of a child's toy that sparkled in the dark. The toy used a polonium-210 inside a ball made of zinc sulphide which emits a flash when struck by an alpha particle. It was also supplied in the 'Uranium-235 nuclear physicist' chemistry set along with radium, caesium and god knows what else (aimed at children).

It is sobering to recall that if you wanted to acquire an X-ray tube in the 1920's or 30's, the best place to buy it was a toy shop (along with the high voltage generator to run it!). 86.130.28.61 (talk) 12:41, 9 October 2019 (UTC)[reply]

The following Wikimedia Commons files used on this page or its Wikidata item have been nominated for deletion:

• Spark plug 3D.stl
• Spark plug render.jpg

Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 08:40, 22 July 2020 (UTC)[reply]

The lead claims the engine block is grounded. I'm no expert, but since most vehicles are electrically insulated from the ground by their tires, I question this. It may be common automotive terminology to claim that connecting to one pole or the other of the battery is "grounding" but commonly being grounded (earthed) requires connection to ...drum beat.... the ground. Simply being at the same voltage as a car's engine block and frame doesn't necessarily mean that voltage is 0V (ground), does it?2604:CB00:1D1C:7A00:889E:5E83:809C:1402 (talk) 01:43, 9 June 2022 (UTC)[reply]

And yet this is the way it's spoken of. We at Wikipedia are powerless to correct this. --Wtshymanski (talk) 22:39, 9 June 2022 (UTC)[reply]

I have looked through the reference, and other unreferenced sources, that suggest that a man named Edmund Berger was the first to create a spark plug:

https://www.gasenginemagazine.com/gas-engines/humble-spark-plug-zmtz20amzhur/

https://www.thoughtco.com/inventors-of-the-spark-plug-4074529

And I have been left with the same statements of “Some historians suggest” or “According to several sources”, where the “historians” and “sources” are neither given or named.

I’m at a point where I question whether this guy even exists. I’m new to Wikipedia so I’m asking if it would be best to remove all mention of him from the article till proper proof can be given for a) his existence b) his invention of what is said to be a “proto-spark plug”.—-UselessPistol (talk) 22:48, 12 April 2023 (UTC)[reply]

Hello UselessPistol, yes it is all quite vague unfortunately. Personally I would like to give Mr Berger the benefit of the doubt, but I would not object if it was removed. Regards, MrsSnoozyTurtle 11:47, 13 April 2023 (UTC)[reply]

I have emailed both websites to see if they may provide the proof for Berger’s invention. I’ll amend the page if they give anything suitable.—UselessPistol (talk) 12:02, 13 April 2023 (UTC)[reply]

That's a good idea! Thank you for taking the extra initiative to do this. Regards, MrsSnoozyTurtle 12:33, 13 April 2023 (UTC)[reply]

Further, others claim that Edmund Berger invented a sparking device for use in remote-detonation of explosives, not a "spark plug" as is used in an engine, and considering the claimed date this would make a lot more sense. https://www.motorbiscuit.com/history-spark-plug/ 98.246.153.16 (talk) 03:45, 14 February 2024 (UTC)[reply]