Radiator/Water Pump Question

[E34 530]

Alright fellow enthusiasts, here's my problem. Through the course of the summer, the coolant level low message appeared on my display about 2 times. I filled it up with a coolant/water mix and it drained out about a month later. Until recently, I thought I either had a leak in a radiator hose or just needed a whole new radiator. As you can see from the pictures, the coolant is leaking from somewhere and is being sprayed all over the engine bay from the fan. Every once in a while, I will find find small stains of fluid on the ground after the car has been driven and has been parked for a while. The fluid consist of either of antifreeze or a watery substance. Two people have told me that they think it is the water pump vs. the radiator or hoses. Is it is a water pump, how much do they cost and about how much will it cost me to get it installed??? (By the way, I did do a search, but all I found were threads about the coolant sensor going wrong.) Any ideas on what the problem could be would be greatly appreciated becuase I really need to get thism fixed. Thanks, Guys, I don't know where I'd be without you.

[Kalevera]

?!

Expect to pay $1000 to have someone rebuild the cooling system -- radiator, hoses, tstat/wp/housing.

Take a look and try to figure out where the leak is -- check for play in the wp bearing (remove the serpentine) and inspect the upper radiator hose, as the fan blade can cut it.

best, whit

[Chris'91'525i]

Instead of installing parts till it's fixed. Why not just have the cooling system pressure checked for leaks.
With a Stant pressure tester you will need them to have the Stant #12030 radiator adapter to hook up the pressure tester.
I know AutoZone loans out tools for free (with a refundable deposit). Not sure if they have pressure testers though.
I'm sure a shop would not charge to much to check it.

[Tiger]

That looks like typical thermostat housing leak. BMW thermostat housing are made of plastic and it cracks at its seams due to age. I suggest you replace the thermostat housing first... make sure you get a new thermostat while you are at it. Aftermarket have full aluminum version which eliminate this problem forever.

If water pump is leaking, you will see leak at the weep hole... most like you would hear rattle as your engine is idling.

Radiator leak is no brainer... it leaks and pools directly underneath the radiator.

If it were me and the cooling system is still original. I would change them all...they all leak close to each other... change radiator... and next thing you know is waterpump rattling... and then there still a leak... thermostat housing.

[E34 530]

That looks like typical thermostat housing leak. BMW thermostat housing are made of plastic and it cracks at its seams due to age. I suggest you replace the thermostat housing first... make sure you get a new thermostat while you are at it. Aftermarket have full aluminum version which eliminate this problem forever.

If water pump is leaking, you will see leak at the weep hole... most like you would hear rattle as your engine is idling.

Radiator leak is no brainer... it leaks and pools directly underneath the radiator.

If it were me and the cooling system is still original. I would change them all...they all leak close to each other... change radiator... and next thing you know is waterpump rattling... and then there still a leak... thermostat housing.

I don't hear a rattle while the engine is idling, so maybe its not the water pump. Thank You all for the suggestions. I am also a member of Bimmerforums.com, and I although I am a new memberto this site, I have to say I like this site 100 times more then bf.c. Thanks for taking the time to answer my questions.

[632 Regal]

if you do the stat and housing, you should complete the rest of the equasion, all hoses, water pump, belts and before you order it all inspect your rad, they sometimes show signs of giving it up especially around the top hose, they also suddenly let go too.

[uscharalph]

?!

Expect to pay $1000 to have someone rebuild the cooling system -- radiator, hoses, tstat/wp/housing.

Take a look and try to figure out where the leak is -- check for play in the wp bearing (remove the serpentine) and inspect the upper radiator hose, as the fan blade can cut it.

best, whit

Parts forr the rebuild Whit is talking about cost me a little over $400.00. My brother and I (Mainly my brother) were able to do the work ourselves.

[genphreak]

if you do the stat and housing, you should complete the rest of the equasion, all hoses, water pump, belts and before you order it all inspect your rad, they sometimes show signs of giving it up especially around the top hose, they also suddenly let go too.

I'm with Jeff and Whit. Why bother to pressure test? 'cos in the same time you can change 2 hoses. Do it once and do it right, anything else is a just going to be a waste of good coolant. You and your engine need to rely on that cooling system, not wait for it to fail again at the worst possible time. NIck

[632 Regal]

All Hoses

[E34 530]

Thanks for the info guys. I hopefully will replace some parts with a friend of mine. Where can I get some of these parts for a decent price.