1998 Craftsman Riding lawn Mower?

Question

My lawn mower starts OK, runs about 20 minutes, and putters and stops. Aftert about 20 minutes to 1/2 hour, it will start OK, and then, about 20 minutes, it will repeat itself and stop. This pattern is consistent. There is gas in the carburator.

Answer 1

The first thing I would do is replace the fuel filter and go from there....It's inexpensive and easy to do .
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If I were you I would ask a question on this forum below.........
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***Questions Answered By Expert *******************Michael
In Category Small Engines (Lawn Mowers, etc.)
http://en.allexperts.com/q/Small-Engines-Lawn-1746/indexExp_107.htm
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Date: 9/19/2006
Subject: craftsman riding lawn mower b&s 19.5
Question
Hi, my lawn mower starts fine, but only with choke on, even if engine is warmed up. As you push the choke in it starts to die unless you push up the engine throttle carefully(eventually it dies after a while anyways). If you put the mower in gear and take off it dies after moving about 5 feet. If you just sat there on it with the choke still on it eventually dies. It basically just dies. Gas coil has been replaced air and gas filter cleaned.
A: The carb most likely has dirt, debris or gummed fuel inside. You will need to remove the carb, ...
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There is a multitude of Q & A's You might find one that fits your description.
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****SEARS Craftsman Bob Villa*****
Maintaining Small Engines
________________________________Try browsing thru this link below.
Good Luck !
Do You have your owners manual and parts list book with all of the trouble shooting information?
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http://www.bobvila.com/HowTo_Library/Maintaining_Small_Engines-Power_Tools-F2200.html

We depend on small engines to do a variety of jobs in the yard. The Fix-It Club knows how to keep them in top condition.
Components of a typical small four-stroke engine used to power lawn mowers, tillers, and other equipment. A two-stroke engine has most of the same components.(click to enlarge)
Small engines are all around us, powering lawn mowers, snow blowers, chain saws, generators, motorcycles, boats, snowmobiles, and many other handy tools and toys. So knowing how small engines work and what to do when they don't will put you in good standing in the Fix-It Club.
A small engine is an internal combustion gasoline engine that produces less than 40 horsepower. To produce power, the engine...
Mixes fuel and air.
Compresses the mixture.
Adds a spark to ignite it.
Exhausts the resulting fumes.
These four steps make up the power cycle. A two-stroke or two-cycle engine mixes and compresses in one rotation, then ignites and exhausts during the second rotation or stroke. A four-stroke or four-cycle engine requires a full rotation for each of the four steps. Most small engines are two-stroke and larger ones, like that in your automobile, are four-stroke. Two-stroke engines aren't as powerful, but they're much cheaper to build. Small engines have one or maybe two cylinders or areas where the explosions occur.
Another important fact is how the engine is cooled. Car and other larger engines are cooled by circulating liquid through channels within them. Because small engines don't develop as much heat, they typically are cooled by the surrounding air.
Maintain a small engine:

Before each use:

Remove debris from the air intake screen, muffler, oil filter, and governor linkage areas with a stiff plastic-bristle brush.
Remove the air intake screen to clean the flywheel fins.
If you are working on a four-stroke engine, check the oil level and add oil as needed.
Twice a year (depending on use and manufacturer's recommendations):

For a four-stroke engine, change the oil. Drain the old oil into a container through the drain plug or pour it out through the filler hole and refill with new oil. (Two-stroke engines don't need this step because the oil is in the fuel.)
Apply a small amount of lightweight oil, lithium grease, or silicone lubricant to all exposed control cable and pivot points (clutch and throttle controls).
Clean or replace any air filter as needed.
Replace a recoil starter rope:

Disconnect the spark plug cable for safety.
Disengage the throttle cable from the housing and remove the housing as needed to access the starter.
Remove the handle from the rope, which is often held in place by a knot or retainer pin.
Unfasten the other end of the rope from the starter using pliers or a cutter as needed.
Knot the end of the replacement rope.
Tighten the pulley counterclockwise all the way, then back it off two turns and hold it firmly.
Thread the unknotted rope end through the pulley hole.
Thread the rope through the housing hole and pull it taut.
Slowly release the pulley, allowing the rope to wind around the pulley.
Attach the handle and reassemble as needed.
Reconnect the spark plug cable.
Clean a foam air filter:

Remove the cover and lift out the foam filter.
Clean dirt and grease from the housing interior with a soft cloth.
Wash the filter with dish detergent and hot water and rinse with clear water.
Allow the filter to fully dry before reinstalling.

Answer 2

The air gap is not a critical measurement so long as there is a gap. With the magnets adjacent to the coil the gap should be set. I don't think that you can install the coil upside down or at least you can't on my Kohler engine. You did not mess up the timing. You would have to remove the flywheel to effect the timing. I would check the spark with the new coil. If you are not getting spark, disconnect the ground wire from the coil and try it again. Most often when a coil is bad they quit completly when they get hot not just make the engine run bad. You could be working on the wrong problem. The first thing to do is determine if you have spark with the new coil.

Answer 3

Gas cap sounds like its clogged.... take it off or leave it loose and try to run it, if it runs good replace it, they can clog and create a vacuume that will stop gas flow...
If this is not it.... replace the plug to be sure, then it sounds like a failing coil, but usually they let you start it back up after a very short cool down (like 5 mins)

Answer 4

there might be trash in the gas bowl of the carurator,or your float might be sticking,sometimes they get pin holes in them and then the float stays down therefor ending up flooding the carburator.also if you left the gas in it from last year it is probably gone bad and started to gel up!therefor making it die ever time part of that gelled gas gets to the carburator!

Answer 5

The coil is getting hot and is shutting down the mower..
replace the coil and it should be fine.