valve guide stem seal insertion tool
2 tools for the different valve stem seals, old neoprene type and new rubber type.
The first tool on the left is used on the older neoprene type seals and is a wider landing. The tool fits onto the metal clip around the seal. I am told that these are now unavailable but they can still be found, with a search. The newer type seals are of 2 different colours, green and brown and are made of rubber with a metal casing. This casing is very thin, hence the tool shape, for it to sit on. They are identical on the insides but differ slightly on the outsides. The new type tool will fit over both seals. Have a careful look into where the new seals will sit. There is a step at the bottom of the landing and the seal only goes up to this point. If you press down on the tool too hard you can spread the seal over this step and render the seal useless, so be very careful and look for this area.
It is about 0.5 mm wider on each side and 1mm tall.