I ran her hard this morning with cardboard in front of the rad and the overheat light came on. Still kicking out sludge but not as much. I also notice that his engine does not seem to make the oil black right away like most diesels I've worked with.
I have been monitoring the engine oil and it looks fine. I have no temp guage but can use a hand held temp reader.
Also, I took the exhaust off and noticed the sludge coming out of the back cylinder.
I repainted the green Yanmar to an International paint code. Motor runs just fine but I am getting black sludge from the exhaust. New injectors and pump looks clean and fine.