Sounds to me like 2 possibilities. THe pushrods weren;t hard enough on the ends. Possibly not hardened properly. Thats why the ends were wearing to a point, which, as they wore, your lash would loosen up. Then, run it for a while, and they would wear some more, loosening the lash, so on and so forth. Then, as the lash loosened up, it would allow the lifter, to bounce on the cam, and that pounds the wheel flat, which, then, it doesn't roll, and or, the pounding, takes the axle/bearings out, and there is a point it says, no more, and you had the problem you had. The second reason could have been a spring issue, causing a fuss point in the valve train, which caused excessive valve bounce, or float, which is hard on stuff as well, causing wear, and the same end result as above
Frank
Advanced Performance
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