spark plug equivalency question

[RB]

I'm told that it is probably due to lower octane and energy fuel we get now that is behind the plug fouling in my small engines around the house, after sever start/run cycles. And, that I should go to an LM type plug to counter this trend.

What LM type plugs can I get that correspond to these:

Champion RN-11YC

Prestolite 14-L7B

AC 45-L

Champion H-10

Champion RJ-19-LM (this one may already be one of the LM types...)

I've searched Google and Vivisimo for equivalency charts, and couldn't find one that has matches for the above:

[TURTLE]

This is Turtle.

Go to Auto Zone or Napa Auto Parts, or Pep Boy auto parts places and they have a book to look them up for you and get any plug known to man for you to look up. The Book or guide will cover any brand of plug that you can spec out. Now if you really wanted to get wild here. You could just ask them to look up the $1.50 plug for you want and size the correct plug that goes in it in 2 to 6 brands. They look up the model number of the mower and tell what the manufactor recommends to put in it.

TURTLE

[RB]

Auto Zone it is. The mowers are so old that the Auto Zone books probably don't even list 'em. But, the ones I listed are right out of my manuals for the machines. So, I'll just toodle over to Auto Zone and hand 'em the list.

[Randd01]

They don't go by application they will cross over your existing plug numbers

[m Ransley]

First ck your spark color, blue is what you need, second go to a hotter plug . Did you ck compression, what you describe is not the gas but just an older motor , rich running, weak internals burning oil, or weak spark. Keeping the same heat range will do nothing even with a different type plug. Also a plug should fire through mild carbon , a dark color plug is normal in small motor design . raise plug temperature and ck everything else, but not firing may be just weak spark. You dont want a yellow spark, thats a weak spark.

[m Ransley]

First ck your spark color, blue is what you need, second go to a hotter plug . Did you ck compression, what you describe is not the gas but just an older motor , rich running, weak internals burning oil, or weak spark. Keeping the same heat range will do nothing even with a different type plug. Also a plug should fire through mild carbon , a dark color plug is normal in small motor design . raise plug temperature and ck everything else, but not firing may be just weak spark. You dont want a yellow spark, thats a weak spark.

[TURTLE]

This is Turtle.

The Auto Zone here has a book for Snapper lawn mowers and Eviruide / Johnson out board motor. Now they do have the cross over books to to see what plug you have and what it matches. Different stores have different books due to what the get a lot of business from.

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[Chip Stein]

snowthrower or OHV plug, maybe honda? don't go hotter leave it as is

not familiar

go to a j19lm that's a techumseh plug and they said in a bulletin years ago to go to a j19lm

LM means lawn mower the r is for resistor, doesn't really matter unless you like am radio while you mow.

spark color only represents what ions are in the air, just like neon lights, same energy different gas.

what equipment do you have?? Chip