Wow! 14 years on a spark plug??? I've never had one last more than 3 years in OPE. Change the **** thing and move on.
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Anybody else experiencing sparkplugs won't stay clean in lawnmowers running E10 pump gas?
- Thread starter FordFETruck
- Start date
My grandparents lawn edger from 1967 still has the original, still working just fine....
I think the plugs today are not (in general) made as well as they use to be. I think the Champion ECO plugs run hotter but that is just a guess from my observations when inspecting them. They always seem cleaner. I think they use better materials and the gap is kept longer. You pay 7 to 10 bucks for one but you may want to cross ref to one and try it.
The plug in the pic looks like oil burning, to rich or misfires. Lots of good suggestions above. Over filling the oil is common. A hoter plug may be a good idea to see if it impacts the debris. If you can find one? I have no problem with someone using the same plug for 14 years but check the gap now and then.
I keep my plugs as long as can and do not worry about hours. Clean and regap as needed. As soon as I have a starting issue that is not obvious, they get changed. Still relatively cheap but not as cheap as they use to be. Heck, I see OEM branded spark plugs at the box stores for over $10. The Same plug in Champion or NGK at the parts stores are ~4 bucks. Maybe the plating is cheaper but they work the same. The surface rust on the metal part of the plug means nothing but esthetics. When dealing with someone else's machine I am more likely to change the plug based on age. For the same reasons said earlier by another member. Sometimes they do go bad or just get weak making starting a bit harder.
The plug in the pic looks like oil burning, to rich or misfires. Lots of good suggestions above. Over filling the oil is common. A hoter plug may be a good idea to see if it impacts the debris. If you can find one? I have no problem with someone using the same plug for 14 years but check the gap now and then.
I keep my plugs as long as can and do not worry about hours. Clean and regap as needed. As soon as I have a starting issue that is not obvious, they get changed. Still relatively cheap but not as cheap as they use to be. Heck, I see OEM branded spark plugs at the box stores for over $10. The Same plug in Champion or NGK at the parts stores are ~4 bucks. Maybe the plating is cheaper but they work the same. The surface rust on the metal part of the plug means nothing but esthetics. When dealing with someone else's machine I am more likely to change the plug based on age. For the same reasons said earlier by another member. Sometimes they do go bad or just get weak making starting a bit harder.
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I use E10 and E85 in small engines all the time, and the plugs don't look like that. I usually ditch the OEM plug from the get-go and put in an NGK plug.
If the OEM plug is running ok , I leave them alone. The Briggs and stratton and Kohler branded plugs in walk behind mowers are Champions and they are good quality. The Chinese engines (like the PowerMore from MTD and some Toro engines) use Brands like Torche which I do not have a lot of faith in. Although sometimes I have seen them do ok. I am much more quicker to replace them with a Champion or NGK. Be wary of online spark plugs that have a reputable brand name. There are a lot of counterfiets out there under the Bosch, Champion brands and others. I always buy my plugs from a local part store because of that and also wanting to support a local business.
Yeah I don't think they are made as well as they used to be either. I've bought a lot of NOS sparkplugs from the 70's and 80's of various brands for cars and mowers. The fit and finish on all of them was always spot on. I've bought a lot of new/newer plugs and noticed the center electrode/porcelain is crooked in the sparkplug body pretty common find across many brands, but I don't recall seeing any NGK's like that. Actually, the plug in the pic (first pic) was still running perfectly and starting first pull I just wanted a good used plug to try my sparkplug tester out with and was kind of surprised it looked like that. The engine never really smokes or uses any oil and it can't be overfilled since the fill port is down at the sump, fill it until its full. I may be guilty of slightly over oiling the air filter, but it never acts overly rich when running so I don't know. I'm seeing this across almost every 4 cycle lawnmower engine I own/come across pretty regularly. The only sparkplugs I've ever really encountered issues with them failing have been the resistor plugs besides this one I saw the spark jumping through the porcelain out by the terminal lol. The new Denso looks pretty good down there nice and shiny though and runs great.
Yeah I leave them alone unless its a Torch or some other off brand plug. I have had a lot of factory B&S resistor champion plugs behave poorly though, so I usually change those out. In 2007 we bought a weedeater mower with a 3.5HP briggs at the end of year for $50 on clearance and it came with the usual RJ19LM. That thing always started hard, never ran right, finally got to the point it quit on me and wouldn't restart. I put a new plug in it and the problems were gone. Another one, when my grandfather passed away in 2018 I tuned up his Husqvarna rider with a V twin Briggs before I sold it, it had 255 hours on it with the original plugs. It started OK and ran fine but the cranking duration cold or hot was always like 3-4 seconds no matter what which I thought was odd so I put a set of NGK BCPR6ES in if I remember right and it would fire off cold or hot just about as soon as the starter would engage. I've encountered this situation a lot of times. My grandfather gave me his 1989 Lawn Chief 500 rider when he bought the Husqvarna, it had what we figured around 1200 hours of use on the original champion CJ8, there was almost nothing left of the center electrode at all, drove it across town running perfectly with that in there lol.
The lady on the chicanic channel swears by this stuff. She says shes had mowers and trimmers sit for a year and fire right up.
Always skeptical of products that YTers swear by until I can try and see results (or not), for myself. I've been watching her channel for years and she is probably one of the most knowledgable and honest folks I've seen. She really knows her stuff and is not afraid to get her hands dirty. When she recommended Ethanol Shield, I did my own little water experiment like she did. It works. This is mainly why I will now pretty much exclusively use ES as my stabilizer and fuel treat for all of my OPE, 4 or 2 stroke.
I use PRI-G in all my stuff. 5+ years stabilized fuel right on bottle. I've had my big saw sit for 3 yrs. unused as the small saw gets the most use and it fires right up.
For what it is worth I have found replacing the CJ8 with a J19LM has worked better. Especially in Tecumseh snow king engines. In the 80's the CJ8 was spec'ed for a lot of flat head engines. The CJ8 is a colder plug than the J19LM and I often I have had easier starting with it as well.
When you sharpen the blade, are you turning the mower on its side, with the carb on the high side? That helps keep oil out of the carb ,combustion chamber.
Exactly! The air filter is likely causing a rich condition.
I deal with this regularly with all of my lawn equipment. The dust clogs the filter, the plug then carbons up and misfires, and sometimes causes random stalling. Cleaning the filter and plug fixes the problem.
Yep for that reason alone I don't really use any CJ8 or equivalents.
These engines you're supposed to tip them with the exhaust side facing up. If you do it the other way its fine but if you turn the blade/engine at all it pumps oil right into the carb via the PCV. I've done it various ways. Anymore I usually just tip the mower back and reach under there with my little impact and have the blade off in a few seconds seems to be the best way to do it. That's usually at the end of the year though when the oil is drained during service anyway.
Yes, that is a Clasic/Sprint/Quartro engine. Always best to tip it when the gas is very low. You can always tip it towards the front to get the blade off. In most mowers the plug is oriented toward the front and you can tip it back. Sometimes I have put heavy weights on the handle bars to hold it down. The general rule of thumb is Carb up for gravity fed carbs. Turn the valve off if you have one. These have the pulse jet carb with the bowl made into the gas tank. They are just a different animal. Very reliable engine for a push mower. Easy to work on. I am sorry they stopped making them. They had a very long run.
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All my lawn mowers ( all over 20 years old ) old Snapper rider and no name push have never had a drop of ethanol. I live on the Carolina coast and have boat gas ethanol free Stations all around me at $1 more a gallon than ethanol.
I buy (5) gallons of pure gas in my gas can, dump Marvel Mystery Oil AND Sta-bil mix in the 5 gallons and use this until I need more...
At the start of the season I pull the plug and hit it quick with a wire brush and a shot of parts cleaner or whatever I have, screw it in and use the lawn mower for the season . I can't remember if I have ever purchased a new plug or not as the wire brush cleaning does the trick.
I would find and use ethanol free with MMO and sta-bil mix and or wire brush the plugs once a year...
Dad taught me to clean plugs as a kid in the 70's, I have recenty stopped replacing plugs in my Harley as cleaning does the trick but I always inspect and IF and the plug needs to be replaced I will.
I would be more worried about the carb than the plugs, I HATE Ethanol!
I buy (5) gallons of pure gas in my gas can, dump Marvel Mystery Oil AND Sta-bil mix in the 5 gallons and use this until I need more...
At the start of the season I pull the plug and hit it quick with a wire brush and a shot of parts cleaner or whatever I have, screw it in and use the lawn mower for the season . I can't remember if I have ever purchased a new plug or not as the wire brush cleaning does the trick.
I would find and use ethanol free with MMO and sta-bil mix and or wire brush the plugs once a year...
Dad taught me to clean plugs as a kid in the 70's, I have recenty stopped replacing plugs in my Harley as cleaning does the trick but I always inspect and IF and the plug needs to be replaced I will.
I would be more worried about the carb than the plugs, I HATE Ethanol!
The mower I posted the pic of has been running ethanol gas since it first came out. The carburetor has been apart and rebuilt 1 time in 48 years of continuous use, I don't think I need to worry much lol. It's on year 16 since the rebuild problem free. Can't say the same for the float bowl carbs though. I recently got one of those sparkplug blasters with silica free abrasive and I gotta say it works very well, gets them clean like new all the way down pretty quick. I always look into them with a flashlight and give them a spray with carb cleaner and air though just to be sure there's no abrasive jammed in there, so far so good with that one. One thing I noticed, the larger the sparkplug (14mm vs 18mm thread) the better it works.
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