These rubber o-rings were in my master rebuild kit for a SBC 350. I really have no idea what they are for. I don not recall seeing anything like this when disassembling the engine. Please help. I have attached a picture..
Thank you.
Scott

 

They are the ineffective O-ring type of valve guide seals.

 

wait so thats an actual valve seal?? You are sopposed to put just them on with out any umbrella seal or anyting? i don't even see how they coudl work alone. I thought your put them on with normal umbrella style seals. I have teflon crane seals that push over the guides and stayput and i also have the o-ring seals. Is this bad?? I started burning alot of oil recently and I think its the valve guides due to massive amount sof carbon on the valves?

 

Yes, those are valve guide seals, loosely speaking. That's all that these motors came with. "Umbrella" type seals are stock on some other motors but not these.

They go inside the retainers, after you put the retainers on the valves, but before you put the keepers in. Some valves have a groove below the keepers for them but not all. ALl they do is keep oil from collecting in the center of the retainer, around the keepers, and running down the valve stems onto the top of the guides.

Using 2 kinds of seals is not "bad"; but IMHO the O-rings are useless if something else is used, just a small amount of dead weight and a little extra work, for nothing.