How to clean this old Brewery bottle?

I got this old neat flask along with a few others when I bought a bunch of Damejeannes from a neighbour today. Now, there's some sort of goo stuck to the flask, both on the outside, and most notably, the gasket was pretty much stuck to the flask itself.

I'm not sure how to clean it away. I've let it soak in a PBW solution ever since I got it, and tried to remove it with manual labour every now and then. The goo is almost a bit sticky, and sugar-y, so I suspect it's old liquid malt extract or something. It's apparently been stuck there since the eighties, and no one has tried removing it. There's also the stuck gasket.

Any ideas on how to get it clean? I'm not sure if I'm going to use this very flask, but it's very decorative and from an old brewery that used to be nearby (this is an off-location island).

Here's a picture of the neck: http://i115.photobucket.com/albums/n312/Hatma/DSCF0320.jpg

(Picture is huge but the detail is useful. This is after a good deal of scrubbing and soaking)

First a soak in hot water and oxyclean, just like we do with any bottles. Let the "scrubbing bubbles" try to loosen and lift all that crap. Then maybe a soak in CLR if it's mineral based. And also high pressure rinsing like with a jet bottle washer.

I don't think pbw has the oxygen bubble factor that oxyclean does, does it?

Hm... I think we've got one of those high-pressure water cleaner things in the garage. That should do the trick.

Revvy said:

First a soak in hot water and oxyclean, just like we do with any bottles. Let the "scrubbing bubbles" try to loosen and lift all that crap. Then maybe a soak in CLR if it's mineral based. And also high pressure rinsing like with a jet bottle washer.

I don't think pbw has the oxygen bubble factor that oxyclean does, does it?

Click to expand...

When speaking of Oxyclean, what formula? I've seen liquid chlorine/fragrance free, and powder, chlorine free.

Bah, now that I cleaned the outside properly, I notice that the incide is entirely covered with this burnt or dried crust. It took a lot of manual labour with a dough scraper to remove it on the outside, and I have no idea how I would remove it from the inside. Maybe with boiling sodium hydroxide or something, but I don't want to handle that. So unless anyone has an ingenious idea for how to clean it, I guess I'll just have to use it for decoration.

pbw does have those scrubbing bubbles.
hot water, pbw and a little bit of time should get it fixed up'

SALUTE!
~XM~