Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Sorry if this is a trivial question, but I have an Ariens 824 and I learned on this site how important it is to keep it greased. So I bought a Briggs and Stratton grease gun and the grease canister it came with lasted me for 3 winters. Now it is time to put a new canister in and I can't figure out how to get the old one out.  I have the spring loaded arm in the opened locked position on the tube that holds the grease cartridge, but the old cartridge doesn't want to come out. I assume this is easy to do, but I just can't figure it out. Any help is appreciated. Thanks in advance.