I adjusted my parking brake yesterday and was thinking about how well the x has been running, and how much fun it’s been. Bad call as the X5 gods heard and visited their wrath on me. Took the car to get dog food and got the dreaded “ding”, with a low coolant message. The bane of my X existence.

There were a couple things that I did, or didn’t do during my motor swap that the little voice in the back of my head told me I might regret. Im batting 1000 so far on that. A quick look under the hood confirmed what my gut was telling me, the heater hose running from the aux pump to the rear coolant manifold had blown. The hose snakes down the the bottom of the motor (no idea why) and back up to the manifold. It has a metal section swedged in this area too, and it looks like the hose came loose of the zip ties I used to keep it anchored and got too close to the steering rack and wore thru. I think it got loose and the column wore a hole in it.

I inspected this hose when I put the new motor in and it looked fine, so I re used it. However, whatever bracket BMW used to secure it on its crazy path under the motor was long gone. Zip ties to the rescue. Clearly not my finest hour.

She didn’t get hot and I’m waiting on parts now. I’ll do the double joint at the same time. My problem is that I can’t figure out the routing around the rack, or the exhaust manifold, which it has to bend around at the back of the motor on its way to the manifold. Nor do I know how BMW secured this coolant line originally.

Good times. Back on the road next week hopefully.

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Current
Original owner 2002 E53 X5 4.4i to 4.6i swap
2026 G80 M3 6 spd
2025 G06 X5 50e
Former
1972 Audi Fox
1986 Saab 900S
1996 BMW Z3
1998 BMW E36 M3 Sedan
2004 BMW E46 M3
2006 Audi A3 Quatro
1993 Mopar 318 Jeep Grand Cherokee
2015 V6 Jeep Grand Cherokee