Civ. Code, § 8460

(a) The claimant shall commence an action to enforce a lien within 90 days after recordation of the claim of lien. If the claimant does not commence an action to enforce the lien within that time, the claim of lien expires and is unenforceable.

(b) Subdivision (a) does not apply if the claimant and owner agree to extend credit, and notice of the fact and terms of the extension of credit is recorded (1) within 90 days after recordation of the claim of lien or (2) more than 90 days after recordation of the claim of lien but before a purchaser or encumbrancer for value and in good faith acquires rights in the property. In that event the claimant shall commence an action to enforce the lien within 90 days after the expiration of the credit, but in no case later than one year after completion of the work of improvement. If the claimant does not commence an action to enforce the lien within that time, the claim of lien expires and is unenforceable.