by bgsengine » Mon Nov 11, 2013 12:11 pm
Valve stem seal is only used on the intake valve.
I would first check if the valve stem itself is worn before attempting to replace the guide - Usually special tools and experience are needed for guide replacement.
Not sure about in the U.K. But stateside, a new head would be a better option if the valve guide is worn - they are surprisingly cheap.
If the engine smokes heavily, I would tend to suspect a head gasket or breather problem before valve guides - while they can lose some oil that way, if they are worn so badly as to make the engine smoke "like a chimney" it won't be the guides.
check your head gasket for any signs that it has burned through between the cylinder and the valve pushrod galley - if it has, then all you may need is a head gasket.
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)