The cam belt and water pump change on the Renault Clio Mk3 1.2 16v is a thorough job that requires engine mount removal, timing mark alignment and — uniquely on this engine — alternator removal to access all of the water pump bolts. The water pump sits behind bracketry and a coolant pipe that simply can't be reached without moving the alternator out of the way.
The belt on this car was original with 78,000 miles — well overdue. Always change the water pump at the same time as the belt since the pump is driven by it and the labour overlap is significant.
Tools & Parts You'll Need
Step-by-Step Guide
Underside Access — Aux Belt, Under Tray & Arch Liner
Start by removing the engine undertray and the inner wheel arch liner on the cam belt side — the liner is held by a few push clips and two T20 Torx screws. This exposes the lower pulley and the auxiliary belt. Undo the T50 Torx bolt on the auxiliary belt tensioner to release the tension, then slip the auxiliary belt off. Set it aside.
Support the Engine & Remove the Engine Mount
Place a trolley jack with a piece of wood under the sump to support the engine. Remove the engine mount — four to five 16mm bolts. Lift it clear. This is necessary to access the cam belt covers behind the mount.
Remove the Support Bracket & Cam Belt Covers
Remove the support bracket behind the mount (four 10mm bolts) and slide it out — this covers both the mount and the upper cam belt area. With the bracket clear, undo all the 8mm bolts around the upper and lower cam belt covers and remove them to expose the full belt, tensioner and pulleys.
Time Up the Engine & Install Flywheel Locking Pin
Using an 18mm socket on an extension bar, rotate the engine clockwise to bring it to TDC. On the cam pulley there's a small arrow on one of the teeth — line it up with the corresponding arrow marked on the cover casing. Mark both clearly with white paint. Remove the lower pulley temporarily to check the crank mark — there's a dimple on the inner pulley teeth that must align with its reference mark. Mark both. Insert the flywheel locking pin to lock the engine in time.
Remove the Tensioner & Old Belt
Undo the 13mm nut on the tensioner and push it around to release the tension. Slip the belt off all the pulleys. Inspect it — this one was original at 78,000 miles with no visible damage, but age and mileage alone make replacement essential. Remove the tensioner completely.
Remove Alternator to Access Water Pump
This is the step that catches people out on the Clio 1.2 16v. The water pump has two bolts hidden behind a coolant pipe bracket that runs across the front of the engine — you cannot reach them without moving the alternator. Disconnect the battery first. Remove the intake air pipe in front of the alternator. Undo the alternator's electrical connections (13mm). Remove the two 10mm mounting bolts and the alternator bracket to give access to the two otherwise-hidden water pump bolts.
Replace the Water Pump
With the alternator out of the way all seven water pump bolts (8mm) are now accessible. Undo them all. Place a container under the engine to catch the coolant that will run out. Use a gentle tap with a hammer to break the seal, then slide the old pump out. Clean the mating face on the block thoroughly with a wire brush, razor blade and fine sandpaper until completely smooth. Fit the new metal gasket onto its locating lugs, then fit the new square O-ring into the coolant pipe port. Locate the new water pump onto the lugs and start all seven bolts by hand before tightening evenly.
Fit New Tensioner, Belt & Set Tension
Fit the new tensioner — the locating pins must face toward the front of the engine and locate into the matching holes in the block before you tighten the nut. Fit the new idler pulley. Feed the new belt (which has direction arrows moulded in — these are important) around the lower pulley first, then up around the water pump and onto the camshaft pulley. Pull the tensioner pin, then insert a 6mm Allen key and turn the tensioner anticlockwise — watch the pointer on the tensioner body move toward the centre reference mark. When centred, nip up the 13mm nut to lock it in position.
Verify Timing, Rebuild & First Start
Pull the flywheel locking pin and rotate the engine clockwise by hand twice using the 18mm socket. Reinsert the flywheel pin — it must locate cleanly. Check both painted timing marks have returned to their exact positions. Only then is the timing confirmed correct. Refit all components in reverse: covers, bracket, engine mount, alternator, auxiliary belt, arch liner and undertray. Top up the coolant, run to temperature and check for leaks.
Key Torque Specifications
🛒 Parts & Tools for This Job
ⓘ As an Amazon Associate, Mr Auto Fixer earns from qualifying purchases. Prices and availability may vary.
🛒 Parts & Tools for This Job
Links below go to Amazon UK. As an Amazon Associate Mr Auto Fixer earns a small commission at no extra cost to you.
Always check part fitment for your specific vehicle before ordering.