Dual extruder oozing issues

I am trying to set up a dual bowden extruder using Slic3r as the slicing software, but I am having some issues with ooze on the non-active extruder. Over time, the inactive extruder begins to ooze and when it finally travels over the part, it will wipe itself on the part, leaving messy trails.

Slic3r has a setting for retraction when the extruder is disabled, and I have been playing with this and it doesnt seem to have much effect. I have tried 5mm, 10mm, and now 13mm and I dont see any meaningful difference in the results. extruder alignment looks good, but I cant seem to get rid of the ooze.

I am using 2 E3D metal hot ends, which seem to ooze a lot less than many of the hot ends I have used before. I am currently extruding ABS at 240C in both extruders, but the problem persists even when I try dropping the temp all teh way down to 225.

Anyone have any ideas what to try next? I see lots of pictures of nice looking dual color prints and I cant believe that they are all cleanup up as much as mine requires.

Have a look at KISSlicer. It has a prime pillar feature, which is a pillar that is built along with the print so the inactive extruder has something else to wipe the ooze on before it gets to the print. I'm not sure how much it would help from the second extruder oozing on the print while the first is going though. You can also have the inactive extruder drop to a cooler temperature while not in use, so it is too cool to ooze.

Set Slic3r to print a skirt the same height at the object with loops = extruders + 1. E.g. if you have three extruders use four loops on the skirt. The nozzles will be wiped when they pass over the skirt.

Andy