[Lured Away]

Easy, finally found the best way after trying all kinds of chemicals. Use a Magic Eraser, wet, and mild soap if want. Cleaned mine to like new white, no sticky residue, no harsh chemicals. Also works great on vinyl. Hell they work great to clean everything and after a couple years I’ve seen no ill effects.

They are just microabrasives.

[trit21]

The problems with magic erasers is they are basically fine fine sandpaper so you are ruining your vinyl seat by causing micro scratches will degrade your vinyl and within those fine scratches mold / mild will be worse. Magic erasers are not allowed on my boat EVER.

[mobil1]

I ruined two vinyl settees using the magic eraser.  Even though the vinyl looks great after the 1st application, the fabric will show wear soon after and eventually degrade as stated in an earlier post.  However, I might try it on an old power cable to test.

[Lured Away]

Simple green and magic eraser did the trick. Still clean a year later.

[sluggo]

I don't know about the cable but I know what works on fenders, and I think they are made with similar materials. Anyway my buddy showed me his fenders and says he has been cleaning them the same way for 10 years, so I would guess it does not break them down. He uses the Works toilet bowl cleaner!! You can get it at the Dollar store. I tried it on my fenders and they came out great!! Squirt some on, brush it around, wipe off, repeat maybe 1 time, and things look shinny new!! Good luck!!

[cernst]

3M General Purpose Adhesive Cleaner #8984 works great. Doesn't damage the cord like acetone does. Works fast. About $20-$30 a quart. Worth every penny. [Only registered and activated users can see links Click here to register] 

[cernst]

Don't use Acetone, it damages the PVC cable and its not good to breath. 3M General Purpose Adhesive Cleaner (08984) is the absolute best! Works fast and doesn't damage the cable...or you. Not cheap but well worth it. Some online aoutstores have it for about $20 qt.

[clcapob]

I always use acetone that clean perfectly, BUT it degrades the cable rubber and after the treatment it attracts dirt more.

[CaptRCA]

Marine Strip is the best cleaner on power cord that I've used and it works great.
Other products may be OK but beware of :
anything too harsh that could damage the cable's outer material, 
Sunlight reaction as it ages,
Attract and collect dirt sticking onto cable,
Becoming slippy so cable will slip on Glendinning.