2003 x5 Coolant Leak

[faranks]

Originally Posted by flatlander

Valley pan. The valley in the middle of the engine has a cover which is prone to leaking. When the coolant seeps out of the cover, it pools in the vee of the engine and can mostly evaporate, leaving you wondering "where did my coolant go??" If the coolant leaks enough it will drop out of two drain holes at the back of the vee by the firewall and then go down by the bell housing. I'm pretty sure that is what you are seeing.

Check the DIY for the valley pan repairs. The updated valley pan is relatively cheap ($11), but the repair is very labor intensive and you have to remove the intake manifold, water pump, coolant manifold, etc to get to the pan. It's a good opportunity to replace many parts that will commonly fail (water pump, thermostat, rear manifold gaskets, Oil separator, hoses, etc.

was just about to do my valley pan gasket and want to make sure that I get the right part. Is it #1 or #3 in this diagram?
RealOEM.com * BMW E53 X5 4.4i Engine Block Mounting Parts
I should have done it while I had the manifold off a while ago replacing those rear coolant hoses and valve covers.
Since this is a huge chore, can anybody suggest anything else while I'm back there again that probably should be replaced (140k).

Also, I remember looking at those two pipes that run above the pan and thinking that looked tough to get them out. Anybody have a preferred way to go? Maybe I should just replace the water pump a 2nd time and take them out the front?

Last question. I remember that hose coming out the bottom of the OSV being fairly pinched back there, wherever it goes. Important? I remember trying to assess what the OSV really does, 2 lines from the top of either head I believe and then the one hose that disappears below...

[flatlander]

It's number 1 in the drawing. It's a cast metal pan with an integrated rubber bead gasket. #3 is just a snap on plastic cap to go onto #1, you don't need to replace it.

[flatlander]

Re: the OSV hoses... Yes very important not to pinch those. They can get clogged anyway with oil/water sludge and if there's a restriction in the hoses it will be more likely to get a pressure buildup.

I would replace the Crankcase vent Valve attached to the back of the intake, along with a new oil separator and new hoses below the oil sep, and the two above the oil sep. Just good insurance going into winter since mine have blown up in winter and caused vehicular fibrillations and migraine headaches!

It's easier to go from the front on the water pump side. Get new o-rings for that. Assuming you've already done the rear coolant manifold.

[faranks]

Where did you see that gasket for $11? I can't find one less than $70...

Do you mean replace the whole rear coolant manifold? or just it's gasket?

[flatlander]

Well... Looks like you're right. The lowest I see now is $68.95.

http://www.autopartswarehouse.com/sh...et/bmw/x5.html

But I swear it was cheaper a few years back. I did mine in 2007.

[flatlander]

Re: the rear coolant manifold, just replace the two gaskets, left and right. Reuse the manifold.

[flatlander]

If you're doing the coolant manifold remember to take out the cabin air filter housing assembly above the firewall so that you'll have room to work around at the back of the engine. Easy to remove.

[phong13]

I am not going to say it's definitely the valley pan, but that is the same problem I had with mine.

[faranks]

Originally Posted by flatlander

If you're doing the coolant manifold remember to take out the cabin air filter housing assembly above the firewall so that you'll have room to work around at the back of the engine. Easy to remove.

Haha, yes I should have done more research before I did all that work originally. I was on top of the motor for a few mins like a monkey f***** a football til I had that same epiphany. It comes out so easily I rejoiced and had 3 beers. I'm still not looking forward to replacing the hose that comes out the bottom of OSV. Then someone mentioned gaskets on the back of the intake manifold, coolant running in there as well?

[sasquatch]

I have to do this repair soon. Not a fun way to spend a weekend.