How to Replace a 350 Water Pump | DIY Step-by-Step

Replacing a 350 water pump takes 2–3 hours and costs $100–$150 in parts, using basic socket tools with close attention to bolt torque and sealant.

The Chevy 350 small-block V8 powered millions of trucks, SUVs, and cars across four decades, and its water pump is a wear item every owner eventually faces. Learning how to replace a 350 water pump yourself saves roughly $150 in shop labor and lets you pick the part quality. The job is straightforward — drain, unbolt, clean, seal, torque — with a few make-or-break details that separate a ten-year fix from a six-month headache.

What Tools and Parts Do You Need?

Missing a specialty tool mid-job turns a 2-hour swap into an afternoon. Gather everything listed below before you drain the coolant.

Step-by-Step 350 Water Pump Replacement

This procedure fits 1968–2002 Chevy trucks (C/K 1500–3500, Silverado, Suburban) and cars (Corvette, Camaro) with the 350 small-block. 1999–2007 Vortec 5.3L/6.0L engines use similar bolt patterns but require removing the surge tank and specific outlet hoses.

1. Drain the system. Disconnect the negative battery cable. Open the radiator petcock or pull the lower radiator hose and drain coolant into the pan.

2. Remove the fan and belt. Loosen the fan pulley nuts, slip off the drive belt, then remove the fan assembly and water pump pulley.

3. Unbolt and pull the old pump. Disconnect the lower radiator hose and heater hose at the pump. Remove the four mounting bolts. Rock the pump gently side to side to break the gasket seal and lift it free.

4. Clean both mating surfaces. Scrape off every trace of old gasket material. Wipe the block face and pump surface with lacquer thinner or acetone until you see clean bare metal — leftover residue guarantees a leak.

5. Install the new pump. Apply a thin, even layer of RTV to both the block and pump mounting surfaces, then position the new gaskets. Set the pump in place finger-tight, making sure the gaskets don’t shift. Torque all bolts to 30 ft-lbs in a staggered pattern. Reinstall any brackets held by pump bolts.

Three errors cause the majority of premature failures. First, skipping sealant on bolt threads that enter water jacket passages — coolant seeps up through the threads and drips steadily. A dab of RTV on each of those bolts before installation prevents it. Second, installing a pump with the wrong hub height throws belt alignment off and wears the new bearings out fast; always compare the hub height of the new pump to the old one before assembly. Third, air pockets trapped in the block after refilling can cause overheating on the first drive — remove the coolant temperature sensor near the thermostat and let air bleed out before sealing the system.