This problem must be either a firewall (including port forwarding or blocking) or a problem with the configuration of the service listening on that port. As @JuergenAuer pointed out, the SSL_ERROR_RX_RECORD_TOO_LONG is basically always a case of trying to access an HTTP service via HTTPS (so the service has been misconfigured without TLS), while ERR_CONNECTION_TIMED_OUT is most often a firewall-related problem.
No, certificates are for DNS labels, not for URLs--the port is irrelevant, as is the protocol (the same cert can be used for HTTPS, LDAPS, IMAPS, etc.). As long as the name matches and the CA is trusted, the cert is fine.