Assuming it's the same as on my 216 it's hollow. The oil exits the shaft through holes in the bottom to oil the rocker arms. Some of those are probably plugged. All you need to do is remove the hold down bolts and remove the assembly. Keep track of what goes where so you can put it back correctly when you're done. Just disassemble & clean it good. Put some assembly lube on the wear surfaces when re-assembling it.
Save a life, adopt a senior shelter pet.
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Name your dog Naked so you can walk Naked in the park.
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