Why did my 320d, E46, water hose burst?
It could be due to age. Split hoses aren't uncommon.
However, it could be due to either a radiator blockage or a cylinder head problem - which is allowing exhaust gases to find their way into the cooling system via a leaking head gasket. When this happens the cooling system becomes pressurised by the exhaust gases.
To check if your radiator is blocked, run the engine until it is hot. The coolant goes into the radiator via the top hose and into the engine through the bottom hose.
Carefully feel the top and bottom hose. If the bottom hose feels much cooler than the top hose, then that indicates a radiator blockage. If the bottom hose feels 'flat' and 'squashed' that is another indicator - though it also can point to head gasket problems.
To check if there are head gasket problems, first check the oil on the dipstick. If it is a 'creamy sludge' then that indicates coolant has found its way into the lubricating system via a leaking head gasket.
Also remove the cap from the raditor expansion tank (where you fill it with coolant/water). Is there any sign of oil/sludge in the expansion tank? Another sign of head gasket problems.
With a COLD engine, remove the cap from the radiator expansion tank and then fire the engine up. Watch the coolant as the engine ticks over ... at first bubbles will appear as air in the coolant escapes. The bubbles should stop after a few moments as the engine warms. If the bubbles continue -or there is 'violent bubbling' that's teling you there is a head gasket problem.
I presume that your car hasn't been overheating or 'running rough' at times, as you haven't mentioned that. Overheating and 'running rough' can also be symptoms of head gasket problems.
All being well .. no radiator blockage or apparent head gasket problems, it is more than likely that the hose burst due to age/mileage.
Aug 16, 2010 |
2000 BMW 3 Series