"Roger Blake" wrote in message
...
I was mowing the lawn today with our MTD garden tractor when it suddenly
and without warning started sputtering and died. The engine is a 14.5 HP
Briggs & Stratton OHV job with electric start.

I checked for obvious stuff like clogged fuel and air filters, and cleaned
the spark plug (it had some carbon deposits). Still no good, the engine
barely catches even with the throttle wide open, backfires through the
carb, and dies. On a car I'd say it sounded like it was trying to run
with severely retarded ignition timing, or too lean a mixture, but I'm
not quite sure what to test on this thing. (This is a 1996-vintage mower,
so I'm pretty sure it has transistorized ignition, not points.) Maybe
some dirt got past the fuel filter into the carb? Any "gotchas" to
be aware of in taking the carb apart?

Any pointers on what to check, or to troubleshooting/tech info online
would be greatly appreciated!

Roger,
If by chance you hit something, the key could have sheared (completely or
partially) and then the timing will be off. You can pull the starter cover
and look at the flywheel to check.

jim.blakely wrote:
"Roger Blake" wrote in message
...
I was mowing the lawn today with our MTD garden tractor when it suddenly
and without warning started sputtering and died. The engine is a 14.5 HP
Briggs & Stratton OHV job with electric start.

I checked for obvious stuff like clogged fuel and air filters, and cleaned
the spark plug (it had some carbon deposits). Still no good, the engine
barely catches even with the throttle wide open, backfires through the
carb, and dies. On a car I'd say it sounded like it was trying to run
with severely retarded ignition timing, or too lean a mixture, but I'm
not quite sure what to test on this thing. (This is a 1996-vintage mower,
so I'm pretty sure it has transistorized ignition, not points.) Maybe
some dirt got past the fuel filter into the carb? Any "gotchas" to
be aware of in taking the carb apart?

Any pointers on what to check, or to troubleshooting/tech info online
would be greatly appreciated!

Roger,
If by chance you hit something, the key could have sheared (completely or
partially) and then the timing will be off. You can pull the starter cover
and look at the flywheel to check.


A compression test will tell if it is a burned valve.

Roger Blake wrote:
In article , Stubby wrote:
A compression test will tell if it is a burned valve.

Compression is 100 psi, which would be low for an automotive engine
but I'm going to guess is pretty much OK in this application.

I pulled the carb off, it is a side-draft Walbro that has a dome-shaped
sheet metal fuel bowl with what looks like a solenoid (fuel cutoff?) on
the bottom. How do I get the fuel bowl off to get inside? I don't see
anything obvious and don't want to force/break anything.

Unscrew the solenoid.

If the engine fires then stops or flutters it's not electrical, solenoid etc.
Although a spark plug can fail best to try a new one

If it was that or a flat battery it wouldn't turn over on the key start

If it was the coil you wouldn't get anything out of it at all they either work or they don't.
Unlikely to be the key because you have to give it a good wack and the only connection is through the belts?

Compression failure is not very common on something of that age. Unless you use it commercially.

Fuel is the most common problem. As long as the fuel is comming out of the inlet there's no need to worry about the float. Remove the main jet out of the centre if there is a slot in it & clean out with an airline. If not it's fixed so you just spray up the middle as best you can. (use a piece of wire to clean as last resort) Take out and spray any mixture jets if it has them. Hold float & needle secure in carb while spraying to avoid loosing any seat from the inlet.

Also check the springs & throttle linkage make sure of no damage.

If no luck it might be best to get a new carb, they can wear up especially on newer types or a carb kit if you have a mixture screw & replaceable jet(s)

Dealers need the nos stamped on the top or about the side of the engine cowling for spares. Nearest dealer can be found at
http://www.briggsandstratton.com/dis...sp?DocID=66467

e.g. 217900 0125 E1 96258674

Good to hear that you are making progress. Keep asking those forum
folks questions, and you'll keep getting answers. It makes for
interesting reading, even if you don't need help with a problem.Another
place I go to with lawnmower/snowblower info is www.opeonthenet.com


GrtArtiste