LT2000 won’t start

[TobyU]

I rebuilt an old cast iron single cylinder Briggs years ago and bought a brand new Champion Spark Plug to put in it. I tried to start the engine and it wouldn't fire, yet each time I tested the spark from the coil it was good and strong, jumping half an inch as I pulled it away from ground.
After taking the plug out 3 or 4 times, checking the gap and spark from the plug, I became quite befuddled. Finally the last time I was looking at the bottom of the plug, I discovered that the porcelain was loose in the steel head of the plug and was moving up and down. Each time I had spun the engine to start it, the contacts were separating so as to change the gap, (too far apart) under the compression stroke causing the plug not to fire. I have not trusted Champions for a long time now. I bought 8 new ones for my Old 89 Chevy Silverado years ago, and had a cylinder that wasn't firing as one of the 7 plugs was junk. I had put new wires, cap, rotor, and other hardware on the truck. Lots of stores sell a cheap sparkplug, that would be a cull to a regular auto parts store. Farm & Fleet is where I got the plugs for 99¢ a piece. Other cheap ignition parts I bought there failed early too !
"Wells Ignition Products" is what they sold, and I will never buy them again either. I don't try to save money by using cheap plugs or ignition parts anymore.
U get sometimes what U pay for, and the trouble out on the road or doing work with a machine, costs a person a lot of time, grief, and even money, to diagnose problums, caused by failure.

Wow I have never actually liked champion plugs for any automobiles other than possibly a Jeep or a Dodge because that's what came in them Factory and they seem to do okay but I would still rather see another brand in those also...they have proved to be simply the Best and the cheapest over the past couple of decades of doing lawn mowers professionally and commercially.
They were available under $2 up until a short time ago until prices started to go up.
I'm not against all the lights either if I get them for the same price but for lawn mowers you simply don't need anything any better than a champion even if something else might be better.
I will say I still prefer them to NGK even though an NGK may start a tad bit easier and maybe run a little bit better but I doubt the average human ear could actually tell these things...
what I will say about NGK is when one of them decides to go, and there's no warning or rhyme and reason, it just goes. I have had a handful of the ngks since doing thousands of mowers commercially that either wouldn't fire when they were fine just days before, or more commonly would start and run for just a few seconds typically about 15 to 45 seconds and then just die or often die with a loud pop.
I've even had two or three Hondas that would pop so hard where they would blow the air filter cover off when they would backfire and then would not start again and it was 100% the plug.
I've never seen a champion do this.
Now as far as your first situation with a damaged plug, more than likely that plug was dropped sometime in its life.
We must remember that once a plug is dropped it is no longer perfect even if it was at one time. Once they plug is dropped it's life can be shortened or it can instantly be no good anymore..
A plug can be dropped after it's already in its box or it can happen in the factory before it even goes into the box or at the parts store when someone is looking at it at the parts counter to determine if it matches the one they're looking for.
But overall, as I said, people are wasting a lot of time when the first thing they go to on a no start or running condition is the spark plug!
Spark plug quality control is actually one of the few things that's really up over the past two to three decades probably due to automation and there's not a whole lot of delicate parts or super high quality materials that are touchy or that can fail.
Then you had the fact that plugs simply don't get found out like they used to because everything just designed and forced by the EPA to use as little gas as possible so it's not like they're typically going to get too much fuel.
It's hard just to keep them getting enough.

 

[TobyU]

You been lucky. I replaced nearly a dozen plugs last year for not firing under compression load. One customer swore the plug was good just because it would spark out of the engine until I replaced it and the engine ran. Matter of fact I got a Chuck Wagon on the yard awaiting a plug this week. I just didn't have the correct plug in stock.

Different OEM plugs have different inherit problems. Then there are the ones that have been dropped a few times before you get them. NGK plugs are normal fairly reliable except for the little 10mm ones. Those CMR ones have numerous failures here. Here I never assume a new plug is good until it is known good.

The plugs I have the best luck with are the Bosch and NGK plugs. Then it goes downhill from there. Besides I get them for about the same as the Champion plugs so I only stock them.

Wow! 12 plugs in a season. That's almost unbelievable to me.
I agree that you never trust a plug 100% until you see it fire and even then you don't trust it 100%, so you don't trust it 100% until you see it run and if you have a concern about spark you always try another known good or one you're almost 100% certain is good.
My point is always that 99% of the time when an engine that won't start a run properly and people go for the plug, they are simply wasting their time because it's highly more likely to be fuel than spark.
I do thousands of these things and as far as no start skill I've done the math on it and it pans out to be about one bad plug in every 450 no starts.
That's an awfully low number.
I also think that NGK are some of the higher quality plugs and not that the average human ear can tell but I think if you were to scientifically test and engine with an NGK versus a champion you would see it start a little bit easier and run just a little bit better than a champion but as I said I don't think the average person can tell a difference.
What I have seen a small number of times but enough to see the pattern is an NGK plug that was just fine yesterday or last week that either no longer starts and runs or the most common thing I've seen will run for just a few seconds and then die or pop as it dies.
Same two or three Hondas blow the air filter cover off when it does this and it was repeatable!
I've never seen this occur with a champion..
I have also never had any problems with Auto lights. I used to use a lot of Auto lights in the 80s and early 90s but not necessarily for lawn mowers and never had a problem. That whole conglomeration company fram, autolite, bendix, signal etc was a lot better in the day and recently I've heard a lot of people who either don't like autolite or simply love to hate them.
I have had no personal problems with anything autolite and from working on cars which you know have at least four spark plugs at a time and often 8 I have only had two bad spark plugs or two spark plugs that went bad after thousands of miles of being good in the past 18 years.
I don't recall ever having a plug go bad prior to 18 years ago as they were simply being changed because it was time and the vehicle was getting a tune-up with plugs and wires etc.

 

[StarTech]

Yes a lot plugs get changed that are not bad. That why diagnostics were important to done. It saves a lot time and money when done. Guessing at a problem can be very costly in the long run.

This is why I recommend doing the non invasive tests first. Yes the upfront of test equipment can be a problem for the DIYer where a shop can quickly recover it in time saved. One of the best diagnostic tools people have is between their ears if they just use it instead letting it collect dust bunnies.

 

[TobyU]

Yes a lot plugs get changed that are not bad. That why diagnostics were important to done. It saves a lot time and money when done. Guessing at a problem can be very costly in the long run.

This is why I recommend doing the non invasive tests first. Yes the upfront of test equipment can be a problem for the DIYer where a shop can quickly recover it in time saved. One of the best diagnostic tools people have is between their ears if they just use it instead letting it collect dust bunnies.

Exactly! Too many people just throw Parts at them hoping to get it right. They've been doing this with cars for decades too.
The sad part is usually by the second or third part they throw at it they luck out and get the car running properly and they still save more money than going to the garage so it reinforces they're terrible behavior and they do it again in the future.
Never replace anything unless you are almost absolutely certain that it is bad. If you're a train tech or even better, have lots and lots of experience, then it's almost never a place anything unless you are 100% certain it's bad.
It's just with the small engine troubleshooting people drive me nuts with not taking the time to actually understand how they work and what they need to work. Of course a lot of this is because they've never had anybody actually explain it to them simply. They end up online or some stupid YouTube video and it's just more overwhelming and too complicated for them so they really don't grasp it
I simply tell people that in today's age of mowers and those for the past 20 years, the most likely problem like 85 plus percent of the time is that it's not getting fuel or not getting enough fuel
So the easiest way to speed up your diagnostic procedure anytime you have a mower in front of you where you don't know the history is after you pull the rope a couple of times and see that everything feels and sounds okay there it simply just won't start....
Pop off the air filter and give it an external fuel source like a 1 second squirt of carb spray cleaner into the carburetor intake hole.
I guess I should note that it's best if you make sure you put your little plastic straw tube in there far enough to go past the choke plate or even open the choke plate with your finger or a tiny screwdriver so you're really getting your external fuel source carb spray in past the carburetor so it can easily get sucked into the engine.
Then, leave the air filter and it's cover off and pull the rope for a five more times to see if it starts and runs for a few seconds.
If it does great! You now know the engine is mechanically sound and all you need to do is get it to flow fuel.
Wait! I did this intentionally but we forgot to do one thing.
When America comes into you and you've pulled the rope a few times and it does not start actually the first thing you should do is check the gas tank!!
If you do this long enough you will have mowers come in where the customer says they can't get them to start and in my creature of habit method I just spray some carb spray in there and then they run for 2 seconds and die but if you look into the gas tank they're dry as a bone.
Sometimes people will actually run a lawn mower out of fuel but forget they did it and when they get it back out to try it they will forget to check and add fresh gas.
Have had a number of them come in that had absolutely nothing wrong with them they just needed some gas put into the tank
To those people's benefit though, most of the time they have been sent in for an annual service or what people sadly often referred to as a tune-up. I refuse to use that word even though many / most lawn mower shops and techs will use it.
I call tune up an evil word that cost people lots of money. Lol
So I will back up and give the best overall troubleshooting procedure.
Better not familiar more comes your Way step one and always the most important
MAKE SURE IT HAS OIL IN THE CRANKCASE!
People will bring you mowers that have absolutely no oil in them or are too dangerous to start because of their low levels or those that have been moved and had the oil poured out of them and never refilled.
So I never pull the rope on any lawn mower or crank a rider without checking the oil first.
Then you check the gas tank to see if there's fuel in it.
This also gives you the chance to look around for any moisture or floaty things in there.
Now you pull it a few times and see that it doesn't start and then you pop off the air filter and give it a squirt in the throat with the carb cleaner.
85% of the time maybe closer to 90% this tells you all you need to know.
Occasionally you will find one that has an air filter so clogged that's the only reason it won't run but luckily as you pull the air filter off to give it external fuel source test you will spot this.
Two birds with one stone kind of thing.
So then, if the mower is simply there for a no start, you clean out the carb by whichever means your accustomed to or you do it the way I feel should not be done and put a new carburetor on there and it's ready to go.
Note that you should also flush some fresh gas through the gas tank and fuel lines and I feel every lawn mower up with fresh stabilized fuel before it leaves.
I don't believe in replacing carburetors when it's possible to clean out the old one or replace needle and seats or floats etc and I don't believe in removing carburetors when you can do everything that needs to be done on the machine.
You can't always do this but 90% of the time you can.
You have to work a little harder as in sneaking your fingers underneath the bottom of the bowl and stuff like that but the amount of time is much shorter.
So in my situation it's better to work harder for a shorter period of time which makes me far more efficient and gets me on to the next more because I have never ending supply of them that I'm behind in doing.

 

[bertsmobile1]

There are 2 big problems with modern plugs.
The big one is that at compression pressures modern fuel ( which is not petrol ) becomes conductive.
So the spark will either fire early or just run down the sides of the electrode insulator.
The other problem is emissions have a maximum permissible lead content of 0.0001 % in most juristrictions .
At that level, lead from the glaze becomes a problem so the nose insulator is no longer glazed.
Thus once a spark tracks down the side it makes a permenant conductive path so the plug is dead .

As for bad out the box , very rarely happens .
Back in the 70's when the machines were less automated, each & every plug got 12 tests automatically as they came out of the machine and were graded according to the test results .
The one machine in the Champion factory in Sydney made every brand of spark plug with the exception of denso & bosch .
The NGK factory in Melbourne did the same thing .
I used to wet my pants with laughter when one "brand bigoted idiot " started sprouting about how much better the brand he used was compared to always bad plugs with other brands .
Now the USA might be different , but I doubt it as the profit on a standard plug is so low trucking them 1/2 across the country costs more than the total profit and his is before the distribution cost to retailers & retail profit.
If you work backwards from what you pay you will see the plug factory gets about the same price as a bolt maker would for a 14 mm zinc plated bolt .

 

[TobyU]

There are 2 big problems with modern plugs.
The big one is that at compression pressures modern fuel ( which is not petrol ) becomes conductive.
So the spark will either fire early or just run down the sides of the electrode insulator.
The other problem is emissions have a maximum permissible lead content of 0.0001 % in most juristrictions .
At that level, lead from the glaze becomes a problem so the nose insulator is no longer glazed.
Thus once a spark tracks down the side it makes a permenant conductive path so the plug is dead .

As for bad out the box , very rarely happens .
Back in the 70's when the machines were less automated, each & every plug got 12 tests automatically as they came out of the machine and were graded according to the test results .
The one machine in the Champion factory in Sydney made every brand of spark plug with the exception of denso & bosch .
The NGK factory in Melbourne did the same thing .
I used to wet my pants with laughter when one "brand bigoted idiot " started sprouting about how much better the brand he used was compared to always bad plugs with other brands .
Now the USA might be different , but I doubt it as the profit on a standard plug is so low trucking them 1/2 across the country costs more than the total profit and his is before the distribution cost to retailers & retail profit.
If you work backwards from what you pay you will see the plug factory gets about the same price as a bolt maker would for a 14 mm zinc plated bolt .

As far as plugs for lawn mowers, I don't see there being any problem.
I've seen in service thousands of them and just the past three or four years and like I stated before the failure rate or problem rate with a plug is extremely low. It's about 1 in 500 and the big deal about this is we don't actually know the history of that plug. Maybe somebody had it out and dropped it on the asphalt and put it back in.
Plugs give so little problems in push mowers and riders and that's why I tell people to stop going to that first because it's just wasting your time.
The only reason people still have this mindset is because of the old days and I'm talking even prior to the push button primer bulbs.
Back before the EPA went nuts and leaned everything out to less than ideal mixture ratios and mowers had chokes, it was very common to flood one out.
There wasn't anything wrong with the plug, it was just wet and fouled or wet temporarily.
People found that if they put a new plug in it would start and run, not because the other plug was bad because they could have simply dried that plug off or burn off the gas with a cigarette lighter for 3 seconds and could have achieved the same results by putting that one back in.
So anyways, old habits die hard as do bad habits and those based on false logic but people still think if your lawn mower doesn't start you should try a new spark plug or another spark plug.
95% of the time maybe 99.5% of the time it's not going to do the tricks so I call it a waste of time.

 

[charleneje]

I haven't read all the replies you got on here but if it is really cold where you are and the mower is not kept in a shed or garage you might want to pull the fuel line and drain the tank then check to see if there is ice in the bottom of the tank or lines, it sounds like the mower started on what was already in the carb from the last time you started it and it didn't get anymore gas due to blockage I had that problem a couple years ago when we had a bad ice storm and I wanted to move my mower under cover.

 

[jerrycmorrow]

Haven’t adjusted valves yet but did replace plug, fuel filter, fuel shut off valve,
oil filter and oil.
the replaced oil smelled of gasoline so replaced oil and filter. The mower was on a slight cross slope with the drain plug on downhill side. Let oil drain for good five minutes.
The other plug was drenched so replaced it
Got it to run but ran poorly so shut it off. Checked oil level and while doing so noticed “creamy” colored streaks in the new oil.
gonna readjust valves and possibly replace oil after I determine what the discoloration is from. If this were water cooled engine I’d call a bad head gasket.
any comments appreciated

 

[S.A.P.]

Haven’t adjusted valves yet but did replace plug, fuel filter, fuel shut off valve,
oil filter and oil.
the replaced oil smelled of gasoline so replaced oil and filter. The mower was on a slight cross slope with the drain plug on downhill side. Let oil drain for good five minutes.
The other plug was drenched so replaced it
Got it to run but ran poorly so shut it off. Checked oil level and while doing so noticed “creamy” colored streaks in the new oil.
gonna readjust valves and possibly replace oil after I determine what the discoloration is from. If this were water cooled engine I’d call a bad head gasket.
any comments appreciated

U need spark, compression, and fuel. I told U that before. I see U have gotten tons of spark plug replies, that U can file in the garbage can. Test the compression and if U have above 60 lbs. it certainly should at least fire. Keep us posted, and I will help U along.

 

[Compact7]

...possibly replace oil after I determine what the discoloration is from. If this were water cooled engine I’d call a bad head gasket.
any comments appreciated

I'd bet a mass of frozen water in the bottom. Enough of it melted during the brief test run to show up in the oil.

I changed the hydraulic fluid in my woodsplitter. Still suffered from slow ram action. After removing the engine to expose the tank's interior, I discovered a slab of ice over a quarter-inch thick and 6- to 8-inches around. The pump would suck the slab tight against the fluid uptake pipe, lol.

Just guessing you may have a mini-iceberg too!