M30 Coolant Overflow

[rreimund]

So I discovered the E34 in a pool of coolant in the garage about 4 weeks ago - haven't driven it since and just got around to looking at it today.

The expansion tank at the radiator was dry, so I topped that off with distilled water. Ran the car until it got hot (sitting in the garage) and it seemed to cool fine. I noticed some weeping coolant under the intake manifold on the drivers side.. but this only resulted in a few drops on the ground. But on the passenger side there was quite a bit... I think I overfilled the expansion tank when I topped it off with water, so I think that might be overflow.. just wondering where the expansion tank overflows to. I can't see any hoses on that side of the car (at the firewall, passenger side (U.S. car)) Is that where the overflow goes to? I do notice there's a hose coming off that side of the expansion tank (#10 at realoem - 7X10MM 17111150232) that doesn't appear to go anywhere else... Damn Bentley is useless in this regard.

I've got some pictures to post later. but wanted to get the question out there sooner rather than later.

[Rus]

If you look at the expansion tank from the driver's seat point of view, there are two tubes that run to/from the tank cap. On the left side is the radiator return hose. It runs all around the driver side of the engine compartment to the top of the radiator. On the other side is the tank overflow tube that runs toward the passenger side of the firewall and then down toward the ground. Where exactly did you notice weeping coolant? There are two coolant hoses that run underneath the intake manifold. These can leak and cause drips. There is also a nest of hoses by the thermostat housing. If those hoses leak at their connections, they can cause coolant to trickle down the side of the block. HTH

[rreimund]

Thanks Zakhar... That does help..

Looks like I overfilled it a bit when I topped it off, so that was the overflow coming from exactly where you describe the overflow would come from.

But my leak is coming from the hoses that run under the intake manifold.. I'm going to top it off and drive it to my mechanic (about 20 miles) tomorrow morning...

I may have to pull over and top it off a few times, so I'll have a few gallons of distilled water with me. Good times.

[rreimund]

Oh yeah, and pictures are here:
http://www.new.facebook.com/album.php?aid=42882&l=c5dd1&id=633488650

[Rus]

Feel around the hoses by the thermostat housing. There are at least three that connect to it on the side. The leaks from these connections usually manifest themselves as a puddle on the side of the block just like in your photos. I had a couple spring up there due to loose clamps. Now I poke a finger in the nest of hoses when checking the oil/coolant/fluids to check for leaks. Also, look at the front-most runner of your intake manifold right underneath the coolant hose closest to it. When it leaks, it leaves a wet spot on the runner. I know its tight around those hoses, but it is possible to poke a finger in there and find the source of the coolant. Should be a simple fix. Keep us updated. :)