They kill mold with a bleach wash.  Bleach and water.  That may work.  Of course, try it on a small sample first.

My wife suggested bleach (also throwing it all out) but I was afraid the ties would get bleached and it wouldn't match up with the new stuff I just ordered. Will try a sample tonight. I suppose the ties could be stained again if they lighten. The layout this is going on will not be ballasted so I was a little concerned.

Bleach may ruin the wood ties, so be careful.  I would wash them with Palmolive soap, then dry them in the sun,  if the smell keeps up, wrap them in newspaper and put them in a brown bag for 3 days, works great for smoke and mildew smells.

Try contacting Gargraves and explain your problem, they may have a solution for you.

Hi Tim, I have never used it for track application but there is a product called "wet it and forget it" that might work for you. I think you can buy it in home centers. Advertised as 

I find that vinegar is more effective on mold/mildew odor than bleach. Never dealt with

it much (and ALL GG ties smell bad, a bit - even new - it goes away over time - assuming

normal usage), but vinegar is less corrosive, too.

But it is corrosive, so just be aware - and keep it away from the inside of the rails.

Give the sun some more time, too - maybe.

Also, just splashing mineral spirits liberally all over the track is a nice, petroleum-based, definitely NON-corrosive way to fight that odor; maybe the best way. (Just don't do it

near any flames, or inside!)

Also, smelling the vinegar always makes me want to hit the salad bar at Ruby Tuesday's.

This is just an off the wall idea, but if you have a can of WD-40 you could do a small test. It was designed to drive off water, and it has a smell all its own, so it might even work, and it certainly will not have the effects of either bleach or vinegar.

Denatured alcohol is another possibility.

Yep! WD-40  works well. It may even let you flex the track again.

Last night I treated a strip with a vinegar spray (we use vinegar for a lot of things so this sounded like a good idea) and then another with WD40. Love that stuff. Didn't get a chance to get out and purchase a mildew treatment.

Gargraves returned my email and suggested hitting it with alcohol and leaving it in the sun.

It's raining here for the next couple of days so I wont see any sun but I will post the results after it clears up and we get a few days to bake this stuff in the sun.

I had this experience with some track I purchased at a local show...   The only thing that worked for me was to use bleach.... It did draw the stain out of the ties...  I neutralized the bleach with water.   Ended up taking a shallow pan put a 1/4 inch of bleach in the pan and soaked the track rather than immerse it in a bucket.  I was surprised at how difficult it was to kill off that offensive odor. 

 As mentioned above, I left them out in direct sunlight for a full day to dry.  I ended up restaining the ties and treating the rails with WD-40 then I applied clear water base poly-urethane to re-seal the ties.  

It finally killed almost all the musty/moldy smell, but it took way too much time and effort.   I didn't try white vinegar...

Note:  The clorox bleach is "corrosive" and effects the plating,  so you have to bring the track indoors afterwards.   I found 2 operating tracks that I left in the garage after doing this, they rusted pretty badly, the other 6 operating tracks that I brought inside are just fine a year later.  I don't purchase wood tie track on line anymore, and if I look at it at a show, the first I do is check it for mold/mildew odors.  

Thanks for sharing your experience Chris.

It is amazing how bad this stuff smells. It fills the room wherever you set it. I'm tempted to just pitch the track and focus on the switches.

I will never buy used again.

Mold remediation calls for a 10% solution bleach to water; 10% bleach any more is over kill.

The "WD" in "WD 40" stands for "water displacement."

The "40" in WD40 stands for the 40th attempt in making the product