Briggs Stratton Model Number 21R707 Carburetor Free Shipping! 3 Year Manufacture Warranty! Replaces Most Briggs Stratton Engines With Model Number 21R707 Carburetor. Replace your carburetor if your machine starts up on choke then dies, if it starts with starting fluid then dies or if it needs choke on to run. It's also a good idea to replace your fuel and clean out fuel lines. Most Problems With Equipment Not Running Or Having a Hard Time Running Is Due To Carburetor Problems. NOTE: Check the appearance, size, shape of this item in our picture and compare with your original one before buying. Generally, we will send the same item as our picture shows. Includes: 1 New Briggs Stratton Model 21R707 Carburetor