Renault 5 Alpine head gasket problems

The 1397 cm³ Cléon engine of the Renault 5 Alpine and R5 Alpine Turbo can develop faults. As an R5 Alpine / R5 Alpine Turbo specialist, Mespiecesauto answers here one of the most frequent failures: head gasket leakage.

The head gasket separates three environments: the hot, compressed combustion gases, the coolant and the oil. A failure can be interne ou externe.

1) Fuite interne

a) Coolant leaking into a cylinder

Symptoms : white smoke from the exhaust, risk of hydraulic lock (conrod buckling), no cabin heating (air pocket in the heater radiator).
Causes possibles :
- Burnt gasket or delaminated cylinder fire ring.
- Fissuration d’une chemise (frequent on tuned R5 Alpine Turbos with lamellar cast iron liners).
- Incorrect head gasket fitting (liner protrusion not respected: 0.02 to 0.09 mm, montage en escalier obligatoire).

b) Fuite de compression inter-cylindres

Symptoms : loss of power, one or more cylinders "not firing", incomplete combustion.
Causes possibles : burst fire ring, poor flatness, incorrect liner protrusion.
Diagnostic : compressed-air injection through the spark plug well at PMH to locate the leak.

c) Compression passing into the coolant

Symptoms : cooling impossible, very hard hoses, expansion tank pressurising and overflowing.
Causes possibles : warped cylinder head, engine overheating.
Diagnostic : a revealing test for CO₂ in the coolant, checking that the fan cuts in.

Stop the engine immediately : if in doubt, switch off the engine to avoid liner cracking, conrod failure and destruction of the block.

Solution globale

Remove the cylinder head and have the cylinder head pressure-tested.
Check the condition of the liners (micro-cracks, seating condition, protrusion).
Carry out the complete metrology of the top end (flatness, liner protrusion 0,02–0,09 mm, roughness, etc.).
Check the vis de culasse (allongement, filetages, couple/angle).

Need help? Download our metrology sheet to guide you step by step.

Parts needed for reassembly

Intake & exhaust valves – R5 Alpine / R5 Alpine Turbo
Complete gasket set – R5 Alpine / R5 Alpine Turbo
Chemises en fonte GS – R5 Alpine / R5 Alpine Turbo

2) Fuite externe

The fuite externe is generally linked to an incorrect liner protrusion.
It is actually the combination of clamping force + protrusion that seals the engine.

The clamping force pushes the liners onto their seats.
The seats then transfer this force to the head gasket.

If this protrusion is incorrect, the head gasket loses its effectiveness and an external leak appears.

Mechanical tip: A simple head re-torque can be attempted, but it is generally more reliable to remove the cylinder head and to
precisely re-check the liner heights with a dial gauge

Besoin d’aide au diagnostic ?

Do not hesitate to nous contacter describing your engine symptoms.
Nous pourrons ainsi :

Établir un assessment of your engine.
Carry out a pre-diagnosis with the essential checks.
Offer you a suitable solution for your situation.

➡️ Need personalised advice?

Head gasket burnt between cylinders

On the 5 Alpine, staggered fitting and protrusion between 0.02 and 0.09 is imperative!

Cracked lamellar cast iron liner, a common failure on the R5 Alpine Turbo engine