I bought a new SLX M675 caliper as the previous one started leaking. I swapped the hose straight over (with hose and lever still bolted to the bike) and began to go through Shimanos official bleed process using their official kit (with one syringe and one funnel). When I start to fill the system with oil using the syringe from the caliper end, oil immedietly starts filling the funnel but there’s little or no air in it, even after several syringes of oil pushed through (around 150ml in total). Then, when I replace the syringe for a tube and a plastic bag and open the bleed nipple to let the oil flow the other way, only a teeny bit of oil comes out, even after tapping the hose and waiting for quite a bit of time.
What’s up? I’ve swapped levers before and remember it as just requiring a little more oil than during a regular bleed to get it right, so this just seems very odd.