RE: Head Bolts on 75 ax
When they are properly-tightened, you do not need threak locking compound. When the cylinder head bolts are properly-installed, they will not come out on their own unless the engine experiences an overheat. Then, the aluminum head will expand more than the bolts, and when it cools down, it will shrink to slightly smaller than it was originally. This will then result in head bolts that will work loose. Thread lock compound is usually not a good idea because it will be very difficult to remove the bolts in the future. You may well wind up making your engine into scrap if you need to do future service.