Just looked at a 82 SD for my daughter. 280K, ugly as sin since it has the top half sprayed with black primer that is peeling off. Everything works, including AC. Engine has what I would characterize in a gasoline engine as a loud knock. Oil pressure is perfect. Has good power and runs smooth at speed. Owner says that he drives it to work every other day. Is the knocking likely to be the nailing problem I have heard about on this forum? He wants $1000, but I will probably offer $800 instead. Any ideas on the knocking? Any help would be appreciated.

Thanks

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Dave

1982 300D
352,000 miles