Hey everyone, first post. I have a JD 300D backhoe I bought used from a guy who had his own business, little over 4000 hours. I had a leak coming from the injection pump gear cover so I figured easy enough, ordered new gasket and replaced it. Well when I took the cover off I noticed the nut for the pump gear inside had contacted the cover and rubbed into it but I had not heard any noise and didn’t think too much of it. then I happened to notice a nut was missing off of the 3 bolts that hold injection pump to the engine. So I found a nut that would fit and tightened them all down until snug and crunk up engine and now it makes a metal screeching sound where I think the nut inside was contacting gear cover before. Any help to fix this would be appreciated it.