sure grip questions, pics inside

I have the twin to that unit under my work bench. More than likely. The two small spiders seized to the croos shaft. The shaft then spins inthe case sheering off the small keeper pin that is .250 in diameter and 1 inch long. Since now the shaft is turning in the case, it eats the case up. At which time the rear makes a bunch of grinding and popping noise. So some one took it apart and figured they would weld it up to fix it. It is junk.