Here's one to keep an eye out for. Having already snapped the plastic tubing from the expansion tank at the point it clips to the air box (common issue), I went to remove the pipework from either end. As I pulled the clip off the radiator end the nozzle on the radiator snapped. Okay, maybe I levered too much on the factory clamp. But when I examined the remnants it was clear the plastic was 'rotten' and the break area had disintegrated into many fragments. Besides I've removed this pipework many times with no issues on other cars.
Old, unloved, high mileage car? Nope
I'm looking into replacing the plastic section of that pipe run. These complete assemblies are about £45 now. They are a known trouble spot, I must have broken at least 3 over the years on various cars. I think the problem is BMW used a type of plastic that isn't entirely suitable for the job. It's called PA12 and is usually used for low pressure air and hydraulic systems at more modest temperatures. I've found a small roll of replacement of the correct type. And it's from a dental supplies company, ie intended for supplying water to the drill. I just don't think it's up to continued exposure to the temperatures found in an engine bay. Anyway, I don't understand enough about different types of plastic to find a higher grade so I'll put back what was there and know it will last another 20 years at least. Just have to work out how to put nice bends in it now. Why the nozzle on the radiator disintegrated is more of a mystery.
Old, unloved, high mileage car? Nope
I'm looking into replacing the plastic section of that pipe run. These complete assemblies are about £45 now. They are a known trouble spot, I must have broken at least 3 over the years on various cars. I think the problem is BMW used a type of plastic that isn't entirely suitable for the job. It's called PA12 and is usually used for low pressure air and hydraulic systems at more modest temperatures. I've found a small roll of replacement of the correct type. And it's from a dental supplies company, ie intended for supplying water to the drill. I just don't think it's up to continued exposure to the temperatures found in an engine bay. Anyway, I don't understand enough about different types of plastic to find a higher grade so I'll put back what was there and know it will last another 20 years at least. Just have to work out how to put nice bends in it now. Why the nozzle on the radiator disintegrated is more of a mystery.
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