Good morning all. I've got a question about a diesel M670 that I hope someone can shed some light on. We have one on the farm here that my stepdad and I restored about 3 years ago. I completely rebuilt the engine. Honed the cylinders, installed new rings, had the injectors and pump rebuilt, and had a valve job done. The energy cells were replaced in one head with new, machine shop made, ones. This engine has been bored to 4.750". I used a diesel injection timing light to set the timing to 9 degrees btdc, as the service manual states. I aligned the timing marks up inside the pump when installed. Static timing mark, on the mounting flange, is on 0. When I removed the pump for restoration, static timing was set to 6. All of the Roosa Master pumps that I've removed have been set to 0. There is a small amount of gray smoke at all engine rpm whether loaded or unloaded. Tractor has good power and starts and runs well. There are no problems with performance. I may be too picky, but the smoke annoys me. I would like for the engine to run clean with no smoke. Is this normal for these engines? Am I expecting too much?