k341 broken camshaft

[DavidBarkey]

Has anyone seen a broken camshaft in a K series engine ? I have JD 316 with a K341 (16hp) that was brought in not running . I got it to run but would not rev out and jumped and banged so bad I thought it was going to jump right out of the tractor . After pulling the engine , removing the pan and pocking a round a bit I noticed the cam was broken off at the back of the gear . The only thing holding it in place was the rod it rotates on and the ends are held tight in the block . Bob @myerslawnandgarden , have you ever seen that before ? If so what would cause that failure ?
I will up load pictures when I get it all apart . I have Mike at Engine Bore sending me a rebuild gasket and seal kit . The cylinder bore has minimum ware. So used cam , valve job and reseal is all I am doing to keep it budget freindly .

[myerslawnandgarden]

The only time I've seen camshafts break, there has been a prior engine failure where a broken con rod gave it a good smack which created a fracture that showed up later. Do you have any history on the engine?

Bob

[DavidBarkey]

The only time I've seen camshafts break, there has been a prior engine failure where a broken con rod gave it a good smack which created a fracture that showed up later. Do you have any history on the engine?

Bob

The owners have had it for years and use it all the time . Never done anything more than general fixes and maintenance s . I have seen this in auto motive along with castistrafic failure .But not signs of that here .

[myerslawnandgarden]

Dave,

I don't have a good explanation for that failure then, other than to offer that it has been running for quite awhile that way. As you note, the camshaft is centered by the pin and sandwiched by the block on both ends, so likely finally wore enough extra clearance at the break to get the valvetrain badly out of time.

Bob