Briggs and Stratton Spark plug question ??
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Why does it gave multiple stickers giving different part numbers? 5062 is a RJ19HX
I would personally use the Champion RJ19HX since that is what it calls for. Or a NGK cross. The RC12 would be a much hotter plug.
I tried a B&S plug from walmart in my mower and it ran like crap. Not sure if I got a dud, but I won't use them again.
I tried a B&S plug from walmart in my mower and it ran like crap. Not sure if I got a dud, but I won't use them again.
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The correct spark plug for that specific B&S engine is the Champion RC12YC which cross-references to a B&S 491055 plug which is what is in there now.
Maybe the riding mower has a replacement engine than what originally came with it; hence the disconnect with the sticker. FYI, the B&S 491055 plug is made by Champion and is just a relabeled RC12YC.
Maybe the riding mower has a replacement engine than what originally came with it; hence the disconnect with the sticker. FYI, the B&S 491055 plug is made by Champion and is just a relabeled RC12YC.
If RC12YC is the correct plug, use NGK BKR5E. If you want iridium, the Denso IK16 will fit, and possibly even the IK16TT 
There's also the Autolite XS3924
There's also the Autolite XS3924
This makes no sense as the 5062 and RJ19HX are short threads style plugs, typically used in flathead engines. The other plugs discussed are long threads. Most OHV engines use a long plug. You'd know right away trying to put one in an engine built for a short plug.
Seems like the case. Ignore the sticker on the mower, it is for a different engine.
Seems like the case. Ignore the sticker on the mower, it is for a different engine.
This was my initial thought as well when I read the OP.
There are two different style plugs listed. If it takes an RJ19LM short plug, definitely don't stick an RC12YC long plug in there. Given that the OP stated it is a 14.5 OHV engine my experience would tell me it needs the RC12YC plug and that is likely the factory spec. Throw one of those in it and motor on.
A bit confusing. I looked at NGK (which I HIGHLY recommend, but also saw some conflicting numbers)
I would contact NGK and ask.
https://ngksparkplugs.com/en/about-us/contact
I love NGK plugs and use them exclusively in the Japanese engines and Predators, but it can be a bit confusing to cross over which ones are actually recommended for Briggs, Kohler, and Tecumseh engines. I find Briggs/Tecumseh/Kohler are not as picky, and will run on a 40 year old plug just fine, so I usually just throw in a new Champion and never have an issue.
It takes a little effort for sure, but seems worth it for me.
I swore in 1975 I would never ever use another Champion plug. I'm sticking with that because whenever someone is over or I'm at their place or at a race, or dock, or garage and there is a no spark situation, taking Champion plug out = 100% has solved the problem.
I've personally never had a bad one, but I know people who have so I get it. My latest struggle seems to be buying actual genuine NGK plugs.
I found that Advance Auto price for NGK plugs is close to others, after the 15% online order bonus, and i am confident it is legit NGK. Of course, I only replace the lawn mower plug every two years, so an extra dollar for peace of mind is money well spent.I've personally never had a bad one, but I know people who have so I get it. My latest struggle seems to be buying actual genuine NGK plugs.
You can use the "reverse engineer a part" tool on sparkplugs.com to find the best alternative to an rc12yc. I entered all the size specs in this link: https://www.sparkplugs.com/search/r...true&specs=165272,165275,165281,165308,165318
Make sure the new spark plug heat range matches the stock (rc12yc) plug. Champion 12 = Bosch 8, NGK 5 and Denso 16. Also make sure the gap sizs is correct for your mower's engine. I think yours is .030". You can confirm that by entering the full model number on the Briggs and Stratton site to get your owner's manual.
If you have to adjust the gap use a wire style gap tool and open or close the plug no more than .008" or you risk putting the precious metal pads on both ground and center electrodes for double platinum, iridium or ruthenium plugs out of alignment. Also, make sure the projection type is the same as the stock (rc12yc) plug or it may hit the piston.
Yes, I realize what I said was probably a mouthful. But I wanted to give anyone else viewing this thread the option of doing it themselves for their specific situation. If you don't want to go that route, post the full engine model number e.g. 287707-1224-E1 and I'll find the best alternative you can go with. I'm assuming you want a long lasting plug?
Make sure the new spark plug heat range matches the stock (rc12yc) plug. Champion 12 = Bosch 8, NGK 5 and Denso 16. Also make sure the gap sizs is correct for your mower's engine. I think yours is .030". You can confirm that by entering the full model number on the Briggs and Stratton site to get your owner's manual.
If you have to adjust the gap use a wire style gap tool and open or close the plug no more than .008" or you risk putting the precious metal pads on both ground and center electrodes for double platinum, iridium or ruthenium plugs out of alignment. Also, make sure the projection type is the same as the stock (rc12yc) plug or it may hit the piston.
Yes, I realize what I said was probably a mouthful. But I wanted to give anyone else viewing this thread the option of doing it themselves for their specific situation. If you don't want to go that route, post the full engine model number e.g. 287707-1224-E1 and I'll find the best alternative you can go with. I'm assuming you want a long lasting plug?
Champion RJ19HX is hotter than RC12. With Champion, higher the number, hotter the heat range.
I tried an experiment with an E3 spark plug and a champion spark plug. I ran the mower empty then put in 20oz of gas if I remember correctly. The E3 seems to get about 30ish minutes or so longer on the same tank.
I've been cross referencing and changing to NGK Iridium plugs in all OPE for at least eight years now. The plugs in my John Deere D140 lawn tractor are eight years old with 250 hour on them. My oldest piece of OPE has an Autolite Iridium replacement for the ubiquitous RJ19LM; everything else in the 4-cycle fleet has NGK Iridiums.
Skip Briggs and Champion (cheap / offset electrodes) and go with NGK platinum. I replace every one (Briggs/Champ) with NGK BKR5EGP or BKR6EGP. Set the gap for 030" for gasoline or 015" for NG or LPG.
If you want to see examples of crooked Champion plugs I have a bunch of them but most go in the trash. Briggs seem far too cheap to be reliable but they do seem to work OK on gasoline. If you're actually putting thought into a sparkplug it should start and end with NGK.
The platinum plugs (single electrode) buy you an ignition performance and reliability boost for not much $$$. Well worth it.
If you want to see examples of crooked Champion plugs I have a bunch of them but most go in the trash. Briggs seem far too cheap to be reliable but they do seem to work OK on gasoline. If you're actually putting thought into a sparkplug it should start and end with NGK.
The platinum plugs (single electrode) buy you an ignition performance and reliability boost for not much $$$. Well worth it.
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Champ Easy start fine wire plugs in my Tecumseh flat head powered snowblowers for at least 7 years, if not more, zero issues.
