valve seals oil usage 94 Corolla

[94pheps]

Hi,
First, my apologies for not being too up on engines.

My 94 Corolla has been using oil at a rate of about a litre to 800 kms or an american quart to 500 miles. The mechanic changed the PCV valve, did not work, did a compression test which indicated good compression. Feels that the oil is blowing past the valves.

Says that the valve seals should be replaced but says that sometimes this repair does not work.

My question is, is the mechanic just being cautious in this warning or what? I read that my car with 150,000kms (90,000 miles) on it could last for at least another 70,000kms. So just wondering on the chances of throwing money away versus enjoying many more miles... It's been a great vehicle to now.