Actually, paint is the best idea. Number 4 (5 with Olympic brand as I recall) deep base tint without adding any color dries clear.

Poly is a terrible idea.

Even expensive spar varnish needs periodic refinishing.

Thanks. Will paint protect against the sun? I live in SC and the bench and table stays out in the elements.

What do you mean paint #4?

Paint mixing is done on site now---using one of four base tints.

#4 deep tint base is paint that is clear until colorant is added.

The reason paint protects better than other finishes(like poly/spar/lacquer/shellac/etc.) is because of the ingredients in the paint. The base tints have all those ingredients, but no final color.

Thanks. Since the bench and coffee table is now old and gray looking, if I paint something transparent to it, will it still come out looking gray?

Or am I supposed to clean the furniture first with something that will take the gray away?

Is linseed oil not a good idea?

You could use a deck wash, but depending on what kind of wood the two pieces are made of and the time they have been weathered, the success of lightening them may not be good.

It sounds as if you need to use paint---pick the color and use a good exterior paint.

Linseed oil is not a viable finish for any wood, as it has just about zero moisture/water resistance. See the link.

Here is a link that might be useful: Linseed oil

For a detailed explanation, see the link below

Here is a link that might be useful: Paint base as a clear outdoor finish

Or you could stain it (to revive the colour) and apply 3 coats of tung oil....which will, when properly applied and buffed, give a waterproof finish with none of the inevitable flaking of surface finishes (such as paint or varnish). If you must insist on going down the sealant route, then a resin based finish, which has a good penetrative effect, will be a better bet.

Trying to stain over that greyness will do little.

Tung oil is a generic term, there are very few(if any) pure tung oil finishes on the market.

Most are a form of varnish and will craze/scale in outside environments.

See the link.

Here is a link that might be useful: Oil finishes

Thanks everyone!