I have run a snake through the floor drain, and the main line. Do I need to run a snake through the vent on the roof?

Most floor drains have a plug slightly on the side after you remove the drain cover. Remove the plug and rod down that opening. You can try rodding from the roof but it's a long shot, you need enough rod to reach roof top to basement floor plus 20' http://www.doityourself.com/stry/how-to-unclog-a-basement-floor-drain

Hi all...

If you don't find a cleanout plug at the floor drain as Ballengerb1 suggested above then you may want to consider snaking through the vent as you asked about... read on.

I always prefer a straight shot compared to snaking through a PTRAP...

If you can gain access to the washing machine vent and snake down that I think you will have a better chance at clearing the drain line well.

If the vent is not easily accessed then maybe you could cut a cleanout into the washer vent and then snake the drain line... maybe?

In my opinion, snaking through a PTRAP (floor drain in this case) is just asking for trouble as you can only fit a small snake around the U shaped bend and if you end up snagging anything you may not be able to remove it through the PTRAP (unless snaking through plug at floor drain), so snaking through the vent pipe is always preferred, if possible.

Are you using a hand-held/hand-powered snake or an electric snake? An electric with a 3/8" minimum cable is best for this job (down the vent... not through the trap).

If you want to discuss more, let me know, OK?

Mark