How to force a page to be removed from the search engine index?

Question

Situation: Google has indexed a page in a forum. The thread is now deleted. How/whether can I make Google and other search engines to delete the cached copy? I doubt they would have anything against that since the linked page does not exist anymore and keeping the index updated and valid should be in their best interests.

Is this possible or do I have to wait months for an index update? Or will the page now stay there forever?

I am not the owner of the respective site so I can't change robots.txt for example. I would like to force the update as the "third party".

I also noticed that a new page on that resource I created two days ago is already in the cache. Given that can I make an estimate how long will it take for a non valid page on this domain to be dropped?

EDIT: So I did the test. It took google shortly under 2 months to drop the page. Quite a long time...

Answer 1

You can't really make Google delete anything, except perhaps in extreme circumstances. You can adjust your robots.txt file to promote a revisit interval that might update things sooner, but if it is a low traffic site, you might not get a revisit very soon.

EDIT: Since you are not the site-owner, you can modify the meta tags on the page with "revisit-after" tags as discussed here.

Answer 2

It's damn near impossible to get it removed - however replacing the page with entirely blank content will ensure that you nuke the ranking of the page when it is respidered.

Answer 3

You cant make search engines to remove the link but don't worry soon the link will be removed as the link will not longer be active. You need not wait for months for this to happen.

Answer 4

If your site is registered with Google Webmaster, you can request to remove pages from the index. It works, I tried and used it in the past.

EDIT: Since you are not the owner, I am afraid that this solution would not work.