I am rebuilding a 1700cc pancake engine.  I looked in the Haynes 
manual on how to put the valves back in and I noticed that it says to 
put on new oil sealing rings aroung the valves.  The picture shows 
something that lookes like a washer that fits onto the valve shaft on 
the rocker side after the valve has been put througn the cylinder 
head.  The problem is that when I took the engine apart there were 
not any of theses rings on my valves.  Did only certain engines have 
these?  Do I need to buy some? Is oil leaking down the valve guide a 
problem with horizontal valves?  Thanks for any help.