Are you testing this with the engine running, or just the ignition turned on ? these old sequential systems draw quite some power, so they do not function very well unless the engine is running.
The old mechanical sequense system only flashes the centre bulb on each side on Hazard.
You may need to take out the sequense system and open it and clean it toroughly, you can still hear the clicking of the sequensing motors, but there may not be contact from the cams and out to the lights
I’m no expert on these systems, but there is a troubleshooting site, http://www.thuntek.net/cougars_unlimited/
And also, there is a sticky thread on top of this subforum forum here about sequential systems, https://cccforum.discoursehosting.net/t/everything-you-wanted-to-know-about-67-sequential-signals/2978/1 where you can ask questions, and get answers, or there may be an answer to your problem if someone else have asked about it earlier