Water Pump Suction Pipe connects to the front the engine block, and is the inlet for the the cooling system.
Overview
Part Numbers
21045-18000 PIPE-SUCTION WATER PUMP 21045-H2300 PIPE-suction, water pump GX
The GX water pump inlet pipe at front of block (PIPE-suction, water pump) has an additional hose fitting for the manifold coolant hose.
21045-H8400 PIPE-SUCTION WATER PUMP A14T
Removal
The suction pipe is a press fit into the block. Put vice-grips on it and tap the vice-grips until the pipe comes out.