My car has almost the exact engine that a W113 has so I thought the following might be of interest as warm weather driving season is upon us.
My W108 has had to have a new head put on it and because of neglect and bad care I ended up replacing camshaft, rockers and valves. I am not doing the work but a trusted long time MB tech is putting it all together.
After the first road test that got the engine up to full operating temperature the car was parked for 10 or so minutes and it was very difficult to start with lean running backfires. The tech then cracked open the injection lines at the injector there was nothing but vapor in the lines. The tech then took the fuel return check valve from another recently rebuilt IP and replaced the one on the engine and repeated the road test - rest cycle and the engine started right away with no lean running issues.
Looking back, I wished I had thought to check the IP check valve. So I wanted to share this for future reference.
Question: Does the check valve have a role to play in holding back enough fuel so that the full amount called for by the pump is supplied? Or is it just to maintain enough pressure to prevent vaporizing the fuel in the system when the car is parked after running?
Brad
