I recently came in the possession of a 1977 300D. The car seems to run great once I get it started. I took it to a local Benz mechanic who adjusted the valves and ran a compression check on it. He told me that three of the cylinders were running at about 340 to 350 while #3 and #5 were running at about 230 and 240 and recommended an engine rebuild at a cost of about $6300. Kind of pricey for a car that only cost me $300.00. My question is since the piston rods seem straight and everything else looks OK, could I pass on a rebuild at this time and just change the valve seals?
Thanks in advance.
P.S. If anybody knows where I can get a copy of the vacuum schematics for this car it will be an early Christmas present.