Looks like you have a pretty standard sump pump pit installation. You are correct in your statement that both Zoeller and Liberty are good brands with good reputations. At
Service Experts Plumbing, we stock and prefer to install the Zoeller M53 this is the all metal construction model with a 3yr manufacturer's warranty. However Zoeller does make two lighter duty models that are considerably less expensive. The Zoeller M72 which is a mixture of metal and plastic construction, as well as the M73 which is all plastic construction. You will find that these two models will sell for about 20% less than the all metal M53 unit. When replacing your sump pump we always recommend the replacement of the check valve at the same time, as check valve failure will lead to premature sump pump failure due to excessive cycling . Also, remember to drill a small hole (about 1/4") in the discharge pipe close to the pump connection, this will help ensure that your pump will not airlock.
