Old tents. Tape on seams disintegrating. Are they for the bin?

I dug out our old back-packing tents to do a bit of cycle touring with the wife, kids & dogs last night and re-proofed them.
However, I noticed that the tape on the seams has become brittle and is flaking off almost all of the seams.

Is it repairable or are they for the bin?
I don’t mind a bit of fiddling to save stuff, especially when they used to be so good.
Phoenix Phreeranger & Phreedome.

you can buy seam sealant and tapes for refurbing them. Easy to apply, works well.

http://www.gooutdoors.co.uk/seam-sealant-p152274

http://www.gooutdoors.co.uk/mcnett-seam-grip-camping-repair-kit-p107601

You could try a DIY retaping with narrow duck tape or rub a wax candle along the seams to waterproof them.

I have some of that seam grip stuff and will take it with me.
Re taping would be better I suspect.

I think the Duck tape would not flex very well – but granted, a lot better than the brittle old shite that is on there at the mo.

Did seam grip with a brush worked fine