FM server comes with its own instance of apache. The terminal-sequence should work (there is another posting here around). But in general, FMS and its components shouldn't go 'disabeled'
What OS version? RAM?
In the past, re-defining the server did also work, no install
We had the same issue with FMS13 as you Hal, It ran OK for a while and then WPE started playing up. At first we could just restart web publishing using the on/off button on the status page, but then that stopped working and not even a full restart would fix. So I did a complete re-install and a day later it happened again so we downgraded to FMS12.0v6 on 10.9.1 Mavericks. That caused problems too with a really unstable WPE so last night I downgraded further to FMS 12.0v5 on 10.8 and have finally found some stability (Fingers crossed)
I would agree with Markus that FMS13 is best left unmodified. We used to run a custom PHP site on the same server but FMS13 forced us to split the Filemaker Server out from the Web server. In hindsight this was a good move as during the 'troubles' I did not have to touch the web server.
Hope this helps