E30 Zone

I've had some gradual coolant loss for a few weeks now on my 325 tourer, so a few days ago, i just went round all the jubilee clips and tightened them up a little (not too much) to ensure that none of them were leaking a little. I also replaced the blue temperature sensor and noticed that no water came out when i removed the old one.

When i took the car for a test drive afterwards, my coolant light came on when it was really warm and when i got home, water was leaking from the large, short hose that goes from the thermostat housing to the flattened metal pipe that runs across the front of the engine, behind the fan.

I took all this off today and the pipe seemed ok - no splits or holes. Took the thermostat housing off and changed the thermostat too after giving everything a good clean up. Filled up the coolant again and bled it at cold, then again at hot.

However, when it had got all warmed up, i noticed blue coolant water dripping (almost pouring) from the rear of the front passenger side wing! I could only imagine this was something to do with the heater, so i turned that on to hot, which seemed to stop it.

Left the engine to warm up a little more, then the hose that runs from the thermostat housing to the water pump starting pissing water out from a small hole that had appeared from nowhere at the top - no where near any join or other obstruction.

So how come i'm getting all these water leaks all of a sudden? This last hose was only replaced about 6 months ago, so it's not perished or aged at all.

Sounds a bit odd. Of course, all the hoses are the same age, so it's natural that they'd start to fail around the same time. It's possible that your tightening up the hoses has disturbed the joints of course, but I expect you've thought of that. Plus you say that you've replaced at least one hose which is now leaking.

When I took mine off last year, there was lots of crusty stuff coating the pipe ends, stopping the hoses from seating properly, I had to scrape this off before refitting. I replaced most of the hoses though.

On stripdown, I did notice that some of the ally parts were severely corroded, and I though it might be due to some Rad Flush, or whatever its called. I had put it in for a week before I dismantled the head, to make sure all the gunk was shifted from the system. I got the impression it had reacted with the antifreeze. Some of the aluminium had gone as soft as cheese, and I thought that this had just happened. I had to replace the little fitting at the backof the head and the thermostat housing.

S'possible? Have you been using chemicals?

Thanks for the response Android, but i've sorted two of the leaks i discussed earlier.

The water leaking from the rear of the front wing was actually from the overflow pipe from the expansion tank, that actually runs through a hole in the wing and obviously lets water drain down inside the wheel arch.

The leak that had sprouted from the newish hose was due to this fouling on the fan. God knows how long it's been doing this, but it had gradually worn down the wall of the pipe to the point that it was paper thin - enough for the pressure of hot water to break through.

Question is now whether curing this will sort out my gradual coolant loss and save me several hundreds of pounds on replacing my head. Only time will tell!