YAY!!! Coolant leak! Need some advice...

[mike_dmt]

Bought my '01 X5 4.4 about a month and a half ago, been great till this afternoon. My wife calls and says the coolant light came on. Fortunately she was at her sisters and not on the freeway.. no overheating

So I go look at it a few minutes ago and while running there's a fairly substantial trickle (constant) from the rear of the engine, down onto the skidplate.

I have been searching through all the valley pan threads, and am thinking it could be a possibility, but I kind of doubt it.

My question is this: since it went from bone dry to a pretty serious leak, could it be one of the hoses on the back of the engine? It seems like it wouldn't be such a constant flow if it was the valley pan... I don't know how much pressure it is under.

If it is one of the hoses, do I still need to remove the intake? Or are they accessible?

This X5 was owned by an indie tech for about 7 years, he has already done a lot of the preventative work for a BMW with 100k. New water pump, radiator, tank, valve cover gaskets,, etc seems like he might have said valley pan... I dont remember 100%

[rocky1536]

I'll be honest... The ccoling system on these cars is pretty weak.

No joke, I've been stranded THREE times because of cooling system failure. It's the only reason my car has ever been on a flat. Even when my mechanic told me some of the hoses were still okay around 100k (4.4 btw) I had him replace every one when I was have a new rad put in. Best $900 I have spent on preventative maintenance and peice of mind.

[IanP]

With a bit of luck it could be the heater water pipes as they enter the bulkhead. I had 2 hoses fail in quick succesion, the first one being the top radiator hose. Like a fool I only changed that one, the heater hose went a week later. Flatbed both times.
You can reach the rear hoses easier with the air intake/pollen filter removed, if you top the engine system up and run it you should quite easily see which hose is leaking. If it is that and not the valley pan gasket I would change ALL the hoses, including the awkward b*gger that is part steel pipe.

[mike_dmt]

Thanks guys, I appreciate the replies. Im going to guess(and hope) its one of the hoses.

It seems like all the valley pan threads pointed at a slower failure (meaning seeping first) and overall leak rate. This one is pouring out pretty good.

I won't have time till Monday to look at it, but I'll let you know what I find.

[mike_dmt]

Found my leak. It looks like the prev owner replaced the cooling manifold on the back of the heads and maybe overtightened one of the hoses. Of course my local stealership didn't have one in stock, so having one overnighted.

My next question concerns the valley pan gasket. I've already got the cabin airbox and stuff out. Even though it's not leaking, how much more work is it to change the gasket? It seems fairly straightforward, what do you guys think?

[HPIA4v2]

Originally Posted by mike_dmt

Found my leak. It looks like the prev owner replaced the cooling manifold on the back of the heads and maybe overtightened one of the hoses. Of course my local stealership didn't have one in stock, so having one overnighted.

My next question concerns the valley pan gasket. I've already got the cabin airbox and stuff out. Even though it's not leaking, how much more work is it to change the gasket? It seems fairly straightforward, what do you guys think?

You need to take the fuel-regulator box, intake manifold and water-pump out to access the valley-pan gasket. (cause you need to remove the 2 coolant pipes running from WP to manifold in the back). I suggest rent a presurize cooling system pump and check first. I replace my valleypan gasket thinking it was leaking when actually the manifold gasket was the one leaking.

[rocky1536]

Just remember, this is one of e few systems on the car that WILL leave your wife stranded...

[HPIA4v2]

Originally Posted by rocky1536

Just remember, this is one of e few systems on the car that WILL leave your wife stranded...

Could be,..., but I starting to hear people got stranded driving newer BMW with electric WP; BMW introduced electric WP started 2006 and on so now they are 5-6 years old and start to fail. Same end result car just overheat and dies by the side of the road. I saw a few iteration of electric WP now, so hopefully the newer ones are more robust. At least on belt-driven one the bearing leaks first or make noise at start up, I need to key in the symptoms on the electric ones cause I have two of them in N54/N55 engines.