I have a 1974 240D with a factory rebuilt engine. The rebuilt engine has a lot of miles on it and recently it blew the head gasket. When I went to take the head off, I found that the camshaft and rockers were warn. I found that it was less costly to buy a rebuilt head on the Internet than to buy all the parts I needed to repair my old head. I discovered that my rebuilt head came with a camshaft with the number 10 stamped on the back. My old warn out head has a tempered type camshaft with the old style rocker arms. I found Mercedes service note 05.4-220/3 which talks about two types of camshafts for use with new rocker arms that have hardened backing. Camshaft code 06 and 08 are for normal power engines and Camshafts with code 10 are for uprated engines. Is it OK to replace my old head with a head that has larger strengthened camshaft bearings and a code 10 camshaft, or should I use my old cam bearings with a code 08 camshaft? What is an uprated engine? Is the block different or is an uprated engine simply an engine fitted with the new style valve caps, strengthened camshaft bearings and a code 10 camshaft to produce more valve lift? If I use an uprated head with a code 10 camshaft do I need new uprated pistons?

Thank you for your help.

Brian D. Wall
brianwall@aol.com