Craftsman Lawn Tractor shuts off.

I have a Craftsman Lawn tractor that needs to be jump started to get going but used to run fine once it started. It will restart on its own once it runs continuously for 10-15 minutes.
As of today, it shuts off if the jumper cable is removed. Could it be alternator? the battery (possible shorted cells)? os something else?
Thanks a lot for your help.
Unni
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Unni wrote:

How old is the battery? Batteries in mowers have hard lives and are only good for a couple of years.
Take it to a mechanic who does mowers and small engines.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The choke is probably not functioning.
All cold engines need a super rich mixture to start. Cheap engines use prime bulbs that you push in a half dozen times, this pumps raw gas up and squirts it into the fuel intake tube from the carburetor. Better engines use an automatic choke flap that engages when the engine is cold then a bimetallic strip opens it when the engine is warm. When you start these the priming is done automatically by the choke.
Something is messing up this system. If the engine isn't run regularly the carburetor passages are probably clogged up with varnish from old gas. If it is a carb system (which I'm sure it probably is) then sometimes pouring out half of the fuel then replacing it with Berrymans' B12 Chemtool and running the engine a bit then letting it sit for a while will melt away the varnish in these passages. Otherwise the carb needs to be disassembled and cleaned.
Ted
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.