During the past year, since taking possession of the AMG DOHC 4V heads and engine, I have spent a considerable amount of time on research.
This particular example was pulled and disassembled over a decade ago. At the time, the heads were sent out for machining but were never completed and many of the valve train bits went missing.
Assuming that the DOHC 4V heads would check out to be sound, I continued to search far and wide for the missing bits and additional reference materials. One gentleman in Germany reached out and provided me with samples and reference materials for each of the missing bits, which could be used to reproduce the bits if needed. I chose to hold out, as I was still confident that the originals could be located that of which included intake and exhaust valves, valve springs, cups and retainers.
There was one potential resource that I had overlooked here, stateside, Mr. Hartmut Feyhl at Renntech. For those not familiar, he was the lead tech/engineer at AMG North America prior to AMG merging with Mercedes Benz and was responsible for all of the authorized DOHC 4V installations in the U.S. during that time. He later formed Renntech and completed a number of AMG DOHC installation there and continues to produce and engineer products for contemporary Mercedes Benz models today.
As a pleasant surprise, not only did he provide the missing pieces, but Mr. Fehyl also took the time to share his invaluable experience with the DOHC engines. The bits arrived last month and work could begin on the heads and block.
The AMG 4V was now back on track…
Everything was sent off to Motor Works near San Diego, CA, where Sergio Bartolino, who had work with these back in the day, began taking inventory, disassembling, cleaning and inspecting. The short block was stripped and proved to be reflective of the low mileage claimed by the previous owner. There was some scoring in one of the cylinders, but everything else in/on the short block passed inspection.
One of the valve seats was suspect and was replaced. Also, the valve guides installed previously were not only incorrect but not properly installed, thus they were removed and replaced.
More progress to follow...