Bicycle Mechanics - stuck internally routed brake cable

i have a nice frame with the rear brake cable routed through the top tube
but there is an old piece of housing stuck in there and i'm not sure how to go about removing it...

can anyone offer any ideas ?

the plastic coating seems to have broken down and formed some crusty bond
pulling on the housing from either end only serves to unravel it
i might be able to pull it out once completely unwound but i'm afraid of the wire braking off inside the top tube..
also, i would still have to scrape? out the old and decayed plastic housing cover somehow

so far i have tried tugging and mild solvents in an attempt to preserve the paint

what the hell should i do ?

i have a nice frame with the rear brake cable routed through the top tube
but there is an old piece of housing stuck in there and i'm not sure how to go about removing it...

can anyone offer any ideas ?

the plastic coating seems to have broken down and formed some crusty bond
pulling on the housing from either end only serves to unravel it
i might be able to pull it out once completely unwound but i'm afraid of the wire braking off inside the top tube..
also, i would still have to scrape? out the old and decayed plastic housing cover somehow

so far i have tried tugging and mild solvents in an attempt to preserve the paint

what the hell should i do ?
Pop both ends back into the top tube. Remove the seat post and work the housing to the rear of the top tube where there is a hole in the seat tube. Remove it. Same with any bits left inside -- tip the bike up on the rear wheel, wobble the frame about a bit and the bits will come to the hole. Use your fingers or whatever to remove. If you don't want stuff going down the seat tube to the BB, stuff a small rag down it to below the level of the hole, and pull it out with crud at the end.

hi rowan,
not sure what you mean about 'popping' but here is some more info for anyone else with ideas:

i can't budge the housing at all
there are vent holes in the seat and head tubes.. they're only about 8mm
it's a steel bike.. i'm assuming there is a small diameter metal tube brazed inside the top tube to carry the housing... the rear derailleur cable is also internally routed this way (and unstuck)

i'm assuming there is a small diameter metal tube brazed inside the top tube to carry the housing... the rear derailleur cable is also internally routed this way (and unstuck)
Maybe try using an old shifter wire. Cut off the old housing near the frame. Feed the wire through and let the barrel end pull the whole mess out. Does that make any sense?

well it was damn near impossible but i got it out..
pulling for about 30 minutes on the housing wire stretched it out enough such that i could wrap it around my hand and yank it out of the top tube

my guess was wrong, there was no inner metal tube, so the only thing left behind was shredded chunks of decayed housing... they were pretty much glued to the inside of the top tube so i used an old spoke to fish them out, not unlike rowan's suggestion... one bit was so stubborn it required a hammer and drift to knock out.. couldn't use a shifter cable because if it had gotten stuck while pulling it would've left no way to push it back out in the other direction

the openings were so swollen i had to work a round file in them for a bit until the new housing would pass through smoothly

thanks