You should be bleeding the fronts from the top bleed nipple (as air will rise to them).
Make sure you're actually backing the nipples out enough to let fluid through. Sometimes it takes more than you might think....
As for the master cylinder. It isn't unknown for an old M/C to pack up upon bleeding, due to the fact it's getting used to the full extent, and any signs of wear or debris soon make themselves known...it's usually the last straw for a half worn M/C.
I'd try bleeding the fronts again and see how it goes. You shouldn't need to do all four wheels as you'll have a dual circuit M/C, so just do the fronts (starting from the one furthest from the M/C and see what happens
As always, this is just my thoughts, and I'm quite often wrong
Make sure you're actually backing the nipples out enough to let fluid through. Sometimes it takes more than you might think....
As for the master cylinder. It isn't unknown for an old M/C to pack up upon bleeding, due to the fact it's getting used to the full extent, and any signs of wear or debris soon make themselves known...it's usually the last straw for a half worn M/C.
I'd try bleeding the fronts again and see how it goes. You shouldn't need to do all four wheels as you'll have a dual circuit M/C, so just do the fronts (starting from the one furthest from the M/C and see what happens
As always, this is just my thoughts, and I'm quite often wrong