2. Check the fit of the valve stem oil seal (205). If the seal does not fit tightly against the valve stem, replace the valve guide (204) (work for a repair shop). 70 – cylinder head, 206 – valve seat.
3. Clean the valve guide (204) with a brush (diameter about 20 mm).
4. Insert the valve into the guide from the combustion chamber side and check the valve movement back and forth. There should be no noticeable gap in the valve guide.
5. Otherwise, the valve guide should be replaced (work for a repair shop).
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