I have an 83 300SD with 210k miles . I bought the car about 8 monthes ago from a friend . When he purchased the car , it had a burnt exhuast valve. He had a rebuilt head installed . Since I've owned the car , it seems to be losing coolant . I had my mechanic check the coolant tank today, and it seems that I have a combustion leak into the coolant . That sounds like a cracked head , but when I looked at the compression readings that were taken a couple of monthes ago , the data reads : 1-200 , 2-300 , 3-360 ,4-300,5-200 . Does this sound like a cracked head , a warped head , or should I be pricing a motor . I don't want to invest a ton of money in the car , I just want some feedback from some other experts .