I'm trying to get grandpas 1440 in better shape than it is. He's had it for 8 years now and not hardly put a dime in it, although he only has 200 acres of corn beans and wheat, but the corns harvested with dads 760 massey... I work at a JD dealer as a tech, so I have mechanical knowlege but these IH combines are a little greek to me. The feeder conveyor chain and sprockets, clean grain and tailings elevator chains and sprockets need replaced. I can get A&I parts through work at a little bit of discount so I was wondering what the quality of these parts were? I was thinking for the acres its hard to justify putting too many dollars in parts from case in it. The other question about the parts is the elephant ears on the front of the rotor are gettin pretty rounded and looks like it might have seen a rock or two(although the cone and rest of the rotor look alright), How are the marlin impellers through a&i?? Ive heard talk of them but havnt really heard if they are any better than factory. The combine does not have a rock trap in it if that makes a difference. Thanks for any help, Its just i'm new to working on axial combines and tryin to get things in better shape because grandpa bein 87 years old he's not doin the best this year and workin full time job cant afford any downtime.