Hi all have a question. I have a JD 216 lawn tractor have a engine problem. It will run good for about 15-20 minutes then start to load up like choke was puled out. Sputters a bit then runs ok then same thing all over. I thought carb at first float to hi. some one worked on this carb before I got it . Now I am thinking coil. All thoughts welcome. R Fink PA