Toyota Alphard: 2AZ-FE Head Gasket / Water Jacket Spacer Failure

The 2AZ-FE 2.4-litre four-cylinder has a documented design defect in the water jacket spacer (Toyota part 16346-28010) that collapses and allows coolant to migrate between the block and head, causing premature head gasket failure. Toyota issued TSB EG013-07 and a revised water jacket spacer kit to address this. If left unrepaired, the head warps, coolant enters combustion chambers, and catalytic converter damage follows. A high proportion of grey-import ANH10 and ANH20 Alphards sold in NZ and AU have already suffered this failure.

• White steam from exhaust on warm engine
• Coolant level drops with no external leak
• Overheating temperature gauge spikes
• Sweet-smelling residue around radiator cap

1. 1

   With the engine at operating temperature, observe the exhaust for white smoke distinct from condensation.

2. 2

   Check the coolant reservoir for brown oily film.

3. 3

   Perform a chemical combustion gas test on the coolant (Bloc-Chek or similar) to detect CO2 from breached combustion seal.

4. 4

   Remove the oil filler cap and inspect the underside for milky or creamy residue indicating coolant contamination.

5. 5

   Ask for evidence of TSB EG013-07 water jacket spacer replacement in the service history.

Parts involved: Head gasket.

$1,800 to $4,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the head gasket or water jacket spacer been replaced under Toyota TSB EG013-07?”
• “Do you have stamped service records showing coolant flushes and no overheating events?”
• “Has the vehicle ever been driven while overheating or with low coolant?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.