Can I insurance claim for accident that occurred months ago due to new damage found?

The insurance company request from insured an immediate notification for each and every claim may arises during the course of the insurance policy and write this condition very clear in the insurance policy , Hence in your case the insurance company underwiter or claim inspector should firstly ask you about reason for late notification of the first claim , if late notification from your side is for a suitable reasons , in my opinion the insurance company will pay you for the old and new claim . if not will payonly for the new claim which you have been notified in the required time.

Bestwishes

if you had an insurance policy during the time of the accident, you can claim on it usually in 3 months or 6 months as a maximum term.