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DLBrooks
DLBrooks
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Rockauto has no listing. A plug from a 49 216 is way to large a thread. It is about a 3/8" fine thread hole --- bolt is a loose fit . Dunno help

Last edited by 42465967; 01/04/2019 8:19 PM. Reason: words
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Bubba - Curmudgeon
Bubba - Curmudgeon
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The diameter of the spark plug changed between 1948 and 1949:

1941 - 10 mm
1948 - 10 mm
1949 - 14 mm

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DLBrooks
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thanks tc, just want to plug the holes --- Did they actually use metric sizes in 41? It is about .394 in inches. I have a locked 48 216-- will see if it still has plugs.


Maybe a champion 842?

Last edited by 42465967; 01/04/2019 9:05 PM. Reason: words
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Bubba - Curmudgeon
Bubba - Curmudgeon
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Yes - supposedly metric sizes were used because the "modern" spark plug was a European/French/Belgium/German/etc invention.


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Kettle Custodian (pot stirrer)
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Check Ebay- - - -just to plug up the holes, there are a bunch of 10MM plugs at very low prices. It's a pretty popular thread size for some single cylinder engines, mopeds, etc. Try an NGK #7023- - - -$2.99 each.
Jerry



"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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Bubba - Curmudgeon
Bubba - Curmudgeon
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14 mm is approx: 0.55 in
10 mm is approx: 0.39 in.

Champion 842 has a 10 mm thread diameter.
NGK 7023 also has a 10 mm thread diameter.

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DLBrooks
DLBrooks
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TC/HL, thanks for the info. Since this is a freebie giveaway - trying to stay low budget. After ----sacrificing--- some pb blaster in the cylinders, 3/8' soft pine wood dowels filled the holes. 8-)



Attachments
plugs.JPG (229.41 KB, 77 downloads)

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Bubba - Curmudgeon
Bubba - Curmudgeon
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thumbs_up

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Kettle Custodian (pot stirrer)
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Works for me- - - -I was about to suggest corks! That keeps moisture and creepy-crawler bugs out! I had a friend who ran a salvage yard who stored engines upside down after draining most of the oil out of the crankcase. He claimed the residual oil ran up around the pistons and rings and kept the rings from rusting to the cylinder walls. Those engines smoked for a while once they were restarted- - - -real mosquito foggers!
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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'Bolter
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My memory may not be right, but seems M8 was A C Delco number for the ten mm spark plugs for the 216. Should still be available easy enough.

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C
'Bolter
'Bolter
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Straying from the subject a bit but the United States was one of the first country's to use the metric system thanks to Hamilton designing our monetary system based on 10's. Why someone didn't get rid of the crappy English system for the rest of our weight/measure/distance is a mystery to me.


Evan
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Bubba - Curmudgeon
Bubba - Curmudgeon
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Hamilton supported Jefferson's proposal for a "decimal" system for currency.

Jefferson proposed a decimal system for weights and measures that was not based the odd English systems, or on French metric system "standards" (which had not yet been established). Jefferson's proposal was dropped due to other "national" distractions. Jefferson probably based his ideas on previous ideas/proposals made by the genius/patriot, Benjamin Franklin (and others).

There was a "Metric Act of 1866", but, by then, industry ruled - it did not want to change "standards" that would be expensive to conform-with/change-to.

Nonetheless - I join coilover in calling the English systems "crappy".

Jefferson and a metric system.
One depiction of Hamilton's involvement in establishing a metric system.

Please excuse my pedantry on this sunny and almost warm Sunday morning.

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When the rest of the world had to rebuild its industrial system after WW II the USA was the only major player left with manufacturing plants that used inch-standard equipment and tooling. Once again, we chose not to follow the rest of the world in switching to metric measurements. Now we're slowly switching over as all that 75 year old equipment wears out and can't be replaced.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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'Bolter
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I seem to remember a nationwide metric initiative back in the 70s or 80s. Supposed to be a 10 year plan to switch everything over. I saw the gas pumps calibrated in liters in some places...


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'Bolter
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Yeah, I was teaching high school back then. Told the kids to get use to it, they wouldn't have a choice. Told 'em they needed algebra too. So much for credibility.
Lots of drugs going around at the time so the "gram" scale got their attention !

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DLBrooks
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I graduated in 71 and I did not have a prob going to metrics but thot it was pushed by tool suppliers to make me buy additional wrenches/sockets. I always thot that they could have just made metic bolt heads etc to fit my existing sae tools -- like 14.xmm. Guess rest of world would hve to change 8-) On the algebra --- glad I had it. Derivatives/Calculus are based on it and Cost Accounting was one of the toughest courses I have ever taken in college. My prob in school was for asking why we factored polynomials. Probabilities/bell curves answers that. Thank a teacher --- 68.

Last edited by 42465967; 01/07/2019 8:38 PM. Reason: words
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Kettle Custodian (pot stirrer)
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The first Datsun cars and trucks that were imported back in the late 1960's had metric thread bolts and nuts- - - -with fractional wrench sizes! The 67 Datsun 4 door sedan I drove for quite a few years was set up that way.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!

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