hello, I just overtook the engine general at my piaggio quartz lc 50 (bj.92) and now I want to renew the coolant among other things. at the bottom of the cylinder I pulled off a hose and thus drained the coolant (not the hose directly on the cylinder). at the water pump wheel directly under the crankshaft you can see, however, some blue liquid, which has no longer drained off. my distributor has now red coolant mi tgeben. do I first have to flush the system so that no rest of the old blue liquid remains or can I fill up directly with this new liquid, which has a different color ? many thanks in advance