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Need help solving a cooling system leak

I have a 2001 530i BMW experiencing an overheating problem. I replaced hoses, radiator, thermostat, water pump, alternator, both belts all of which went fine. However still loosing anti-freeze, it seems to be coming from under the intake manifold. Does anyone have suggestions of step by step instructions on removing it to get to the problem?

Oh-oh. I don’t like the sound of this. But I tell you with sincere sympathy.

You need to first start with a cylinder leakdown test. You may have a blown headgasket. If so, you need to address it immediately. What happens with a blown headgasket is that

  1. the cylinder blows gasses at up to a few thousand degrees directly into the water jacket, adding heat to the coolant faster than the cooling system can dissipate it.
  2. the gasses blowing on can also imncrease pressure in the system. They could be forcing the cooolant right past a breech in that headgasket between the water jacket and the outside world.
  3. The engine can also draw coolant into the cylinder in the intake stroke and cause corrosion there.
  4. and, if there’s an oil passage included in the breech, the coolant can contaminate the oil…and it’s a lousy bearing lubricant.

I’m hoping I’m wrong. I’m hoping that BMW uses part of the intake manifold gasket to seal part of the cooling system, like GM does. But I’d do a leakdown test pronto.

I’m assuming this is a V8.
Is that correct?

The 2001 BMW 530i only came with the 3.0L inline 6.

The reason I assumed it was a V8 was because BMW had a previous 530i which was a V8.
Looks like I learned something again.
But, like everybody posting here, I haven’t worked on every car out there.

I had a minor leak around the top of my radiator and I put in a tablespoon of coarse ground pepper in the tank and the leak stopped. Two years ago and still no leak. Maybe it will only work with very small leaks. Pepper will not disolve in water but will flow to and, sometimes, fill and seal a leak.