1. Since valve maintenance is a complex job and requires special tools and equipment, this job, commonly referred to as "valve bulkhead", must be carried out by a specialist.
2. You can independently remove and disassemble the head, perform a preliminary cleaning and check, then reassemble it and send it to an auto repair shop, where the valves will be lapped. Performing an inspection will assess the condition of the head and parts of the valves and therefore determine how much work and what new parts will be required when servicing the valves in an auto repair shop.
3. The auto repair shop will remove valves and springs, restore or replace valve seats, restore valve guides, check and replace valve springs, turning mechanisms, spring plates and crackers (if necessary), replace the valve cups, reassemble the valve parts and check the height of the installed spring. In case of deformation of the mating surface of the cylinder head with the gasket, it will also be processed.
4. After high-quality regrinding of the valves, the characteristics of the head should be like a new one. After returning the cylinder head from the workshop, be sure to clean it before installing it on the engine, removing metal particles and abrasive dust that may have remained after servicing the valves or resurfacing the head. If possible, blow out all oil holes and passages with compressed air.