Rootbeer flavor is not good in beer

[clowder]

Can anyone give me some advice on how to get rootbeer flavor/smell out of my keg? Much to my dismay, a friend asked me to keg him a batch of rootbeer. The last two batches of beer that I've put in that keg, still has a strong rootbeer flavor and aroma. I've cleaned/sanitized/soaked the keg several times. I changed all the o-rings, keg lines(gas also), and took apart and cleaned the tap.
Any help would be awesome. I really don't want to have to buy a new keg, unless I absolutely have to.

P.S.
The rootbeer was good, but not worth ruining the beer.

[spiderwrangler]

Yes, this is a known issue. Most folks that make root beer dedicate a keg/line to the stuff as it tends to linger...

[brewinhard]

Try brewing up a dark rich roasty style beer that will hopefully absorb/mask some of that root beer nuisance. RIS, robust porter, American Stout, etc). Otherwise try a different cleaner. Have you tried PBW followed by a star san or iodophor rinse?

[The Beast]

I agree with Brewinhard. One of the beers that I get the nmost requests for is a Root beer stout that I make towards the beginning of the summer. Typically I just add some root beer extract at bottling time. I have made a few batches and it always gets good reviews by friends/ family. Ive never kegged it, but now that I think about it, I do have a Keg I use for pop that I let the kids make for parties and such, I dont know why, but I never thought of putting it in there........

[jwatkins56550]

The poppets could be harvesting some flavor, take them out and smell them.

[Bugeater]

If you use a keg for root beer and want to use it for regular beer, you need to replace ALL rubber/plastic parts including the poppets. It is almost impossible to get the taste out of them. I learned the hard way. Now I just have a dedicated keg for root beer.

On the other hand, I did find that the flavor is not bad at all in a nice dark robust porter.

Wayne