Triband antenna ordered

I'd noticed in the past few weeks that reception on FM 2m (and 70cm for that matter) had got worse. I have a dual band collinear, of unknown manufacturer, mounted atop a 8 foot aluminium mast on the chimney. This has been up for the best part of 15 years and is now showing it's age. I think something is corroded or the cable has been damaged in some way.

The existing dual band antenna
Yes I know it could be any old antenna
but it's the one I currently have in operation on 2m/70cm

So I have just ordered a brand new Diamond V2000 tribander, good for FM on 6m, 2m and 70cm to suit the Wouxun quadband FM tranceiver I have. As I can't hear anything on 10m with the Wouxun I'm not too bothered that the aerial is just a tribander.

I ordered a fresh 5 foot 1.5" aluminium pole, 25 metres of Messi & Paoloni Ultraflex 7 and some matching M&P PL259 plugs. Hopefully this will cure my deaf rigs - I know the problem is the existing antenna as every VHF/UHF rig I own is equally deaf.