heater matrix?

just swap the pipes over in the engine compartment where they attach at the bulkhead and go through to the cabin, water goes in through one, through the matrix then back out through the other one, so when you swap them over the water goes through the other way ect.
or you could disconnect the pipes and put a hose pipe on one of the matrix pipes then keep swapping the hose pipe over which will flush water through bothways

ste
February 2005