Water Leak - E34 540

[MrDevine 14]

Just noticed last couple weeks – small amount of water leaking from what seems to be just before the engine block. Happens after air con has been going full blast.

Took it for a VTNZ WOF on Tuesday (it passed) comments was 'appear water leak from the radiator'. Is this a water pump, expansion tank, hose?

Liquid is odourless and appears to be water, I'm not sure if it has coolant in it or not. I checked the coolant tank and it looks 3/4 full, but on the 540 its hard to tell where it should be.

Temperature has remained steady in the middle of the dial, so no overheating yet. Due for a service on Monday, best not to drive it till then?

Anything I can do in the meantime?

Ace, C.

[kiwi535 538]

Just noticed last couple weeks – small amount of water leaking from what seems to be just before the engine block. Happens after air con has been going full blast.

Took it for a VTNZ WOF on Tuesday (it passed) comments was 'appear water leak from the radiator'. Is this a water pump, expansion tank, hose?

Liquid is odourless and appears to be water, I'm not sure if it has coolant in it or not. I checked the coolant tank and it looks 3/4 full, but on the 540 its hard to tell where it should be.

Temperature has remained steady in the middle of the dial, so no overheating yet. Due for a service on Monday, best not to drive it till then?

Anything I can do in the meantime?

Ace, C.

air conditioning removes moisture form the air as a natural phenomena as it cools the air.That water is recondensed as is left to drain out of the system.Is normal

[Wom 0]

yea probably just condensation from the aircon

if it was coming from the cooling system then it would be slightly discoloured and would have a slight odour too because it would have antifreeze in it

[turbolizard 38]

Took it for a VTNZ WOF on Tuesday (it passed) comments was 'appear water leak from the radiator'. Is this a water pump, expansion tank, hose?

The guys above are right - cold water is produced by the air con and can be seen dripping out under the car BUT I would be surprised if VTNZ got confused by water from the air con. They may not always be totally onto it, but this would be a very elimentary mistake for them to make, so it is worth mentioning when you take it in for service.

You also mentioned the leak is "just before the engine block". If you mean at the front of the engine then it is not the air con. The plastic resin thermostat housing on the V8 engines often crack and leak a tiny amount of coolant. As mentioned by others, this will have a sort of sweet smell to it.

After all that - probably just water from the air con - but that is back at fire wall.

[MrDevine 14]

Yeah I mean the water appears to be coming from behind the engine, not near the radiator at the front of the block. Agree VTNZ not always onto it, but they had a look under the car. Would expect the fluid to smell some if it had antifreeze in it, thats why I suspect its just air con condensation.

Thanks for the responses guys, will get mechs to doublecheck on Monday. (I'm going to BM Workshop in Gay Lynn – Albany is too far way for me Glenn)

Ace.

[Guest Simon*]

If you can narrow down the source of the water even further it may be the heater valves - prone to fail in E34's unfortunately

The unit sits on passenger side firewall and has a black plastic cover over the top. Run your hand under the piping and see if it's wet there.

Diagram is somewhat hard to follow with all parts exploded but look for the actual pump/valve unit in the centre with all the hoses running off it

[MrDevine 14]

Hey Simon thanks for that. The water leaking is condensation from the air con unit, so says BM Workshop. But the VTNZ guy was right, the radiator is leaking.

Gonna get that replaced next week. $740 installed sound about right?

[twisted 45]

Hey Simon thanks for that. The water leaking is condensation from the air con unit, so says BM Workshop. But the VTNZ guy was right, the radiator is leaking.

Gonna get that replaced next week. $740 installed sound about right?

Mine was done before i got the car, and the receipt is for closer to $350. Definately not top notch work though.

[Guest Simon*]

Not too sure on that price actually, Glenn may give you an approximate price range to expect. Is it an OEM radiator? Perhaps you could price one yourself from BM Warehouse and compare?

[MrDevine 14]

Isn't the expensive bit – fitting the radiator, doing all the bleeding of coolants etc?

[MrDevine 14]

BM Warehouse say Rad is $490 incl GST. So $250 for labour sounds OK to me. Looks like a complex job. Would have to assume using genuine parts?

[Guest Simon*]

Absolutely. Sounds good to me - just worth checking that out in my opinion

[BM WORLD 1264]

pretty easy job to swap radiators on these 540i's . 30 to 50min .

[MrDevine 14]

Hey Brent – I'm not all that mechanically minded – do you need to bleed the coolant system and adjust? Read on the internet that can be a bit of mucking about.

So you think $740 fitted and installed is on the high side for this? It sounds reasonable when you consider I just paid $280 for a service (which based on past experience is pretty good)

C.

[*Glenn* 854]

Yes $740 is a reasonable price. And yes it has to be bled properly. A few other things they need to check while doing it...I'm sure they will let you know though

Edited January 11, 2010 by *Glenn*

[MrDevine 14]

Thanks Glenn.