What goes wrong
The factory RTV sealant, used to seal the timing chain cover to the engine block, may have been improperly applied during assembly. This can create a small void or channel through which pressurized engine coolant can escape, leading to an external leak. Over time, this leak will worsen and can lead to low coolant levels and potential engine overheating if not addressed.
Symptoms to watch for
- Sweet smell from engine bay
- Visible coolant drips or stains under the front of the vehicle
- Low coolant level in the expansion tank
- Engine overheating (in severe cases)
Root cause
Improper application of RTV sealant during engine assembly at the factory, leading to an incomplete seal at the timing chain cover.
Buy time with these
- • Regularly check coolant level
- • Visually inspect engine for leaks
Permanent fix
- Reseal timing chain cover with new RTV sealant (e.g., Three Bond 1282B or equivalent) and replace coolant and engine oil.
- Inspect and replace any coolant-contaminated belts or components.
Related recalls / TSBs
FAQ
What causes coolant leak from rtv sealant?
Improper application of RTV sealant during engine assembly at the factory, leading to an incomplete seal at the timing chain cover.
How much does it cost to fix?
National average $1,200–$2,500.
Is this a DIY repair?
Difficulty 3/5. Reseal timing chain cover with new RTV sealant (e.g., Three Bond 1282B or equivalent) and replace coolant and engine oil.
What are the symptoms?
Sweet smell from engine bay; Visible coolant drips or stains under the front of the vehicle; Low coolant level in the expansion tank; Engine overheating (in severe cases)