This comes from two owner threads, and neither says which engine the car had. One was a low-mileage car with its original radiator, and the other had a puddle by the driver's side jacking point. Both threads are short, and one never says what was found.
The signs
- The red coolant warning light comes on, and the header tank is low.
- A puddle under the car, or streaks on the underside of the front clam.
- A leak that only shows when the engine is warm. One owner had no loss on a five-minute drive with the temperature reading about 76 degrees, and guessed his leak was after the thermostat opened. That was a guess. A hose leak in another car only happened when the engine was warm and driving, which made it hard to see with the car stationary.
Where to look
The only places that can leak at the front are the bleed nipples, the hoses and the radiator. Check these.
- The header tank. Check it hasn't cracked.
- The bleed nipple on the hose into the top of the radiator, and the point where that hose attaches to the radiator. It is behind the passenger side headlight. Reach it by removing the headlight and not through the wheel arch. See Changing the coolant and bleeding the system, which notes that the one behind the headlight is known to be weak.
- The hose clips. A loose radiator hose clip let a small amount of coolant past, only when hot, and tightening it fixed it.
- The radiator core. The joint between the core and the end where the hose attaches is a known weak point on the original radiator. It starts weeping and can eventually blow apart suddenly, dumping all the coolant. Another leak was from the underside of the core. Replacing it is a front clam off job, so not a cheap fix. See Radiator replacement and Front clam removal.
- The hoses and pipes at the sills. See below.
Telling the radiator from the hoses
Shine a light into the grille. If the coolant is pooling in the crash box, it is likely the radiator core. If it pools outside that, it is likely the hoses. One owner checked, found it in the crash box, and concluded it was the core. That also explained why the coolant appeared from under the clam and streaked across the front undertray. He had already checked the bleed nipple and both hose connections and found no leaks, and the trails were on the driver's side, the opposite side from the bleed nipple.
How to find it
- Get the undertray and arch liner off. Undertrays can disguise where a leak comes from, because the coolant runs along them. Get the car up on ramps or jacked up, run it, and look with a torch.
- Look from below. Run it up to temperature and get your head below the level of the radiator with a torch.
- Pressurise it. Squeeze the hoses with your hand to put a little pressure on the front of the system and look for drips, or borrow a pressure tester pump and look at all the possibilities.
A leak near the sill
One leak was on the driver's side by the jacking point, and the owner wondered whether a hose in the sill had split. The coolant pipes in the sills are hard pipes, so you won't be pulling those anywhere. There are also lots of specially shaped coolant hoses at each end of the sill that might not be easy to replace with regular hose, if one of them is the source. One reply first said any hose from any supplier would do, then said he may have been thinking of the charge cooler pipes. It is unlikely to be the sill pipes themselves, and if you are lucky, it will just be a corroded clip that has failed and popped off. The thread doesn't say what was found. That car's belt was also squealing, which is probably a separate issue.
After finding it
In the 2017 thread, one owner had a new Coolex all-aluminium radiator fitted by a garage, and another, who had the same symptoms, ordered one with new hoses, because all his were original at 14 years and 81,000 miles. The Coolex fins are said to damage very easily, and it is otherwise a straight fit.