Search yielded no results, sorry if this is a double post. Anyway, FYI I was recently helping someone troubleshoot some problems at SearchEngineWatch forums and it struck me that I should write an article about this and other issues. Because sometimes when you run into a brick wall and can not figure out why your site is not getting listed or even crawled in the search engines it is not always a site issue. http://www.textlinkbrokers.com/blogs/more/234_0_1_0_M/
yes Server Issues which can affect Search Engine Rankings, if your site down means it will affect your site's SERPS
yes, when your site down or overload, google can't crawl your site. This is mean a 'crawl error' then google will give you lower priority at SERP...