Briggs and Stratton engine runs rough sputters after it gets warm

[bertsmobile1]

Any way to tell if coil is bad?

ILENGINE told you how to do it way back in post no 5.
For novices I recommend you go one better & buy a COLOR TUNE from a company called GUNSONS.
They are in the UK and do web sales to the USA.
Look at the video on their site to see how it works.
Then at least you will definitely know if you have an electrical problem or a fuel problem and weather a fuel problem is rich or lean.

 

[reynoldston]

ILENGINE told you how to do it way back in post no 5.
For novices I recommend you go one better & buy a COLOR TUNE from a company called GUNSONS.
They are in the UK and do web sales to the USA.
Look at the video on their site to see how it works.
Then at least you will definitely know if you have an electrical problem or a fuel problem and weather a fuel problem is rich or lean.

Yes very good idea. But you are looking at a tool with shipping 30 to 40 dollars which will only be needed one time for a home owner. You can buy a spark tester in this country from most any auto parts store for less then 5 dollars. For this 40 dollars will be able to tell how rich his engine is running which can be done by just looking at the spark plug for free. I would say just remove the coil and take it to a dealer, have it tested, and most dealer will test it for free if you need a coil you buy it from them. If he doesn't want to spend the 5 dollars for the plug tester just take one of his many used plugs and open the gap to 1/4 inch and test it like I told him, another free test. My guess here is this is just a home owner with very limited resources.

 

[ILENGINE]

Be aware also that the certain briggs engines built after 2012 use a plug with a gap of .020 as opposed to the older engines that used .030, the wrong gap on the newer engines has been linked to a misfire.

 

[bertsmobile1]

Yes very good idea. But you are looking at a tool with shipping 30 to 40 dollars which will only be needed one time for a home owner. You can buy a spark tester in this country from most any auto parts store for less then 5 dollars. For this 40 dollars will be able to tell how rich his engine is running which can be done by just looking at the spark plug for free. I would say just remove the coil and take it to a dealer, have it tested, and most dealer will test it for free if you need a coil you buy it from them. If he doesn't want to spend the 5 dollars for the plug tester just take one of his many used plugs and open the gap to 1/4 inch and test it like I told him, another free test. My guess here is this is just a home owner with very limited resources.

No you are looking at a tool that will ship in a Royal Mail fixed rate small package for ｣ 6,00 worldwide just tha same as a USPS flat rate worldwide small packet.
I still use mine at least once a week and I have acquired the skill set / experience to read plugs that the OP has yet to master.

 

[reynoldston]

a Royal Mail fixed rate small package for ｣ 6,00 worldwide .
.

Sorry I have no idea what you saying here. I got the price with shipping from E-Bay which is in dollars. Yes it looks like a nice idea and I see nothing wrong with it and the more ideas the better for the OP. If the OP wants to invest into such a tool it would be a good investment for him or a shop. I am just making a guess he is just a home owner and trying to fix this problem as cheap, fast, and easy as possible for a one time fix. Also it could be something different other then ignition like a tight valve. or other heat related things like too heat next to a fuel line.

 

[bertsmobile1]

Sorry I have no idea what you saying here. I got the price with shipping from E-Bay which is in dollars. Yes it looks like a nice idea and I see nothing wrong with it and the more ideas the better for the OP. If the OP wants to invest into such a tool it would be a good investment for him or a shop. I am just making a guess he is just a home owner and trying to fix this problem as cheap, fast, and easy as possible for a one time fix. Also it could be something different other then ignition like a tight valve. or other heat related things like too heat next to a fuel line.

Well actually the EVILBAY vendors want $ 47 + $ 22.95 P & P flat rate to anywhere in the USA ( world actually ) , a tad under $ 30 - $ 40.
Off Amazon they are $ 67.+ $ 11 P & P anywhere in the USA
And if you go to the Gunsons web site they will either post direct or send you to a local vendor which is generally cheaper.

Value for money depends upon how much the OP thinks their time is worth and how much he is willing to invest in parts that did not need to be replaced.

 

[jgaspelin]

The mower has spark as I can mow my entire yard. Takes about 45 minutes. The engine runs smooth 10 seconds or so then sputters just a little. If cutting through thick grass the sputtering seems to stop. I took off the Kill wire and let the engine brake slow the engine down. No sputtering when the break was on a little.

Could coil still be going bad. I may just wait till it doesn't rune then take to a small engine repair place. Can't post video of it running or I would.

 

[jgaspelin]

I may just wait till it gets worse to take to a mechanic

 

[bertsmobile1]

follow the kill wire back to the coil.
If the roughness goes away when it is disconnected chances are there is a patch where the insulation is not good and the kill wire is making occasional shorts .

 

[ThaxtexGM]

I have cleaned carburetor, changed spark plug, got new gas, and changed flywheel key and adjusted magneto spacing. The engine runs cuts entire lawn but sputters instead of running smoothly. I also put stabil in gas.

hi jgaspelin make sure you put a copper core spark plug in it, all new NGK are, see how that goes.