Valve spring compressor.

[big o]

Compressors used to remove valve retaining clips,releasing valve.

 

[Bi11Hudson]

Way back in the dark ages, BC(before computers), shade tree mechanics used a worn out socket and a 1 pound hammer. The hammer released the spring, the socket kept the lock ring pieces close in. There was a contraption that was sort of like broad reach Vise Grips to install the valves once they were ground.

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