How to Flush a Car Engine Block

An engine block flush is a relatively simple thing to achieve without having to visit a garage. Flushing out accumulated dirt and other forms of build-up from the cooling system will help your engine to run more smoothly for longer. For many cars, it may never be necessary to flush the engine block – it’s only vehicles that aren’t driven for an extended period or go a long time without oil changes that might need a full flush out.

The procedure can be quite complex, and for that reason it’s best done by a professional.

Step-by-Step Guide

The basic steps to flush a car engine block are:

  1. Remove the lower radiator hose and catch the draining coolant in a bucket.
  2. Remove the top radiator hose and flush the system out with a normal hose.
  3. Continue until the water runs clear out of the bottom of the engine.
  4. Refill with coolant and reattach the radiator hoses.

The exact process will differ from vehicle to vehicle, so consultation of your vehicle manual will be essential when it comes to performing a flush of the cooling system. A mechanic will be able to recommend if it’s actually necessary, so make sure you check with them before taking any action.

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