Crawl Properties: Update / Set Crawl Properties

$ssaName="Search Service Application"

$context=[Microsoft.Office.Server.Search.Administration.SearchContext]::GetContext($ssaName)

$daily=New-Object Microsoft.Office.Server.Search.Administration.DailySchedule($context)

$daily.BeginDay="25"

$daily.BeginMonth = "1"

$daily.BeginYear = "2010"

$daily.StartHour = "2"

$daily.StartMinute = "30"

$daily.DaysInterval = "1"

$contentsource = Get-SPEnterpriseSearchCrawlContentSource -SearchApplication $ssaName -Identity "Local SharePoint Sites"

$contentsource.IncrementalCrawlSchedule=$daily

$contentsource.FullCrawlSchedule=$weekly

$contentsource.Update()