Honda Integra: B18C cam seal and distributor O-ring oil leaks

The B18C DOHC engine has dual camshaft front seals and a distributor O-ring that harden and crack with age, producing external oil leaks onto the timing belt cover, exhaust components, and surrounding bay surfaces. Near-universal on original-seal DC2s over 100,000 km. Oil contaminating the timing belt accelerates belt degradation, compounding risk of belt failure. Should be renewed at every timing belt service.

• Oil staining on the timing belt cover and surrounding engine surfaces
• Oil smell from the engine bay when the engine is warm
• Visible oil seepage around the distributor base at rear of head
• Oil-contaminated timing belt with orange-brown discolouration

1. 1

   Inspect the front of the engine for oil weeping around the cam seals and distributor base.

2. 2

   Check the timing belt for oil contamination or discolouration.

3. 3

   Look for oil deposits on the engine underside near the front.

4. 4

   Confirm whether seals were replaced at the last belt service.

Parts involved: Timing belt.

$250 to $550 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.

• “Have the cam seals and distributor O-ring been replaced?”
• “Any visible oil leaks in the engine bay?”
• “Was the timing belt changed with fresh seals or was there oil contamination at that service?”

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.