To the best of my knowledge they were not prone to head problems. 70&#039;s were probably as close to being bulletproof as any tractor Oliver built, I still see them in daily service today. Most head cracking problems are not a problem with the engine, but an operator malfunction, regardless of manufacture. Overheating is the main culprit. Watch your temperature and coolant level. When replacing a head or head gasket, at bare minimum have the head &#039;decked&#039;, take it to an automotive machine shop, they have gages to &#039;deck&#039; it, or check for warpage. If warpage is found it is a simple matter for them to put it on a broach and mill it straight. Make sure all surfaces are clean enough to eat off of. You will find that heat and dirt are the biggest enemies of any engine. They were made to work, but also they require periodic maintence. As to the part # maybe someone else can help out there. If you are looking for a head you might ask Paul W. Rode, Jr., he has several heads, engines, etc. maybe he can sell or trade something that will get you going. He also has several 70&#039;s in his &#039;boneyard&#039; that I think still have a head.