The risk of using a hammer is it is easy to damage the bush and the tube because they are made of soft metal. When this happened, the workers had to be very careful, but even so, sometimes the bush and the tube were damaged and people can not see it from inside.
This situation had a negative influence to our bearing in the same application, we talked with our customer and decided to change some things together. We made the tolerance of outer diameter of our bush smaller, meanwhile, we decided the matched tolerances between the bush and the tube together to be more reasonable. The sample was very successful.