M103 valve stem seal installation
 

A quick question on installing the valve stem seals. Mercedes provide 6 (I think) protective sleeves with the seals. Are these meant to be installed and left on the valves, between them and the seals, presumably on the inlet side? Or are they just present to aid installation, and so should be removed once the seal has been snapped into place? Thanks

The plastic sleeves are used to protect the seals when you slide them over the valve end. Remove them once the seal is installed.