Coolant Leak

[san]

Hi,

I have a 2006 Ci ZHP which has 96k miles on it... Coming to the problem, I havent driven the car for 4 days now, and so I thought Il just start the car up. I noticed a patch of water leaking from the bottom of my car and when I checked the coolant level, it was completely dry... Looking under the car, the leak seems to trickle down from the end of the black plastic cover...

The ambient temperatures are getting lower and close to 0Celcius, could this have any effect? I am not sure if the previous owner had anti freeze or not...

What could cause the coolant leak? Where should I start looking?

[kayger12]

If nothing had been changed in the cooling system it could be any of a number of parts. Cracked expansion tank, thermostat housing, or weeping water pump are all good possibilities. Hoses and radiator would be less likely but possible. Could also be as simple as the lower hose temp sensor o-ring.

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[san]

If nothing had been changed in the cooling system it could be any of a number of parts. Cracked expansion tank, thermostat housing, or weeping water pump are all good possibilities. Hoses and radiator would be less likely but possible. Could also be as simple as the lower hose temp sensor o-ring.

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Could you tell me how I can check for those?

[san]

If nothing had been changed in the cooling system it could be any of a number of parts. Cracked expansion tank, thermostat housing, or weeping water pump are all good possibilities. Hoses and radiator would be less likely but possible. Could also be as simple as the lower hose temp sensor o-ring.

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Also can it fail just like that when I havent driven in the past 4 days?

[kayger12]

Start her up, let her warm up, and look for the leaking fluid. If the cooling system is all original it's all about ready to be replaced anyway so you should consider a cooling system overhaul.

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[san]

Start her up, let her warm up, and look for the leaking fluid. If the cooling system is all original it's all about ready to be replaced anyway so you should consider a cooling system overhaul.

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I think all the fluid is out cause the xpansion tank level was showing empty... and i think the cooling system is all original.... Is it safe to run the car without any coolant?

[kayger12]

I think all the fluid is out cause the xpansion tank level was showing empty... and i think the cooling system is all original.... Is it safe to run the car without any coolant?

Nope. Unless you'd like to warp your head and replace the cooling system via a new motor.

Pick yourself up a cooling overhaul kit and get her done. Lots of good diys available.

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[danewilson77]

If the cooling system is original (or you have no maintenance history in this regard) you need to overhaul asap. Now sounds like a good time.

"No flamesuit required"

[san]

Nope. Unless you'd like to warp your head and replace the cooling system via a new motor.

Pick yourself up a cooling overhaul kit and get her done. Lots of good diys available.

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by running the car without any coolant, i meant warming it up to see the leaks, not driving it (my bad should've been more clear) lol....

[san]

If the cooling system is original (or you have no maintenance history in this regard) you need to overhaul asap. Now sounds like a good time.

"No flamesuit required"

Yup will start looking for kits right away

[danewilson77]

Yup will start looking for kits right away
Good deal.

"No flamesuit required"

[san]

Did a quick search and found this -

http://www.ecstuning.com/BMW-E46-330Ci-M54_3.0L/Engine/Cooling/

Which level of overhaul do you guys think I need? Thanks!

[BCS_ZHP]

ECSTuning.com has a kit available, check there & the dealers too. If you're over 75K miles, at a minimum I'd do expansion tank, ET cap, lower radiator hose, upper radiator hose, water pump, thermostat housing, and lower radiator hose temp sensor. You'll also need a gallon of BMW coolant & mix it 50/50 with distilled water. Several DIYs on here for this maintenance, allot yourself 4-5 hours to do it properly.

[danewilson77]

I went with stage I I, and a Behr radiator.

"No flamesuit required"

[danewilson77]

I got my stuff from ecs as well.

"No flamesuit required"

[BCS_ZHP]

You shouldn't need a new radiator unless you're over 125-130K miles.

[san]

I got my stuff from ecs as well.

"No flamesuit required"

Did you buy the genuineBMW kit or the ECSTuning's assembled kit?

[kayger12]

by running the car without any coolant, i meant warming it up to see the leaks, not driving it (my bad should've been more clear) lol....

Lol. My bad. Based on the mileage I'd just bang out the overhaul.

Let us know if you need anything.

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[kayger12]

I went BMW

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[BCS_ZHP]

Just me, I always buy genuine BMW, never have ever had any issues. Will the aftermarket stuff work, probably, have never tried it.

I treat the cars like my wife, would I ever give her fake diamonds, and what would she say if she ever found out that I did.....and thus I always go OEM.

[kayger12]

Just me, I always buy genuine BMW, never have ever had any issues. Will the aftermarket stuff work, probably, have never tried it.

I treat the cars like my wife, would I ever give her fake diamonds, and what would she say if she ever found out that I did.....and thus I always go OEM.

Especially with the cooling parts. I've seen way too many premature failures with aftermarket cooling parts

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[danewilson77]

Did you buy the genuineBMW kit or the ECSTuning's assembled kit?

I think I bought the ecs kit but I'm not sure. I did have to subsequently change out the expansion tank again, but I wanna say it last about 40 to 50k miles. I'll go look at my maintenance history.

The friendliest forum on the planet.

[danewilson77]

Yep. About 50k miles on the tank. Confirmed. I used the ecs kit.

http://tapatalk.imageshack.com/v2/14/11/09/b89a97d333e7ae308fd1ac821903bbaf.jpg

http://tapatalk.imageshack.com/v2/14/11/09/a9b2f9977d51a5bab5d184dab86f47a9.jpg

"No flamesuit required"

[kayger12]

Sounds about right. Latest bmw tank is good for at least 90k

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[san]

Just me, I always buy genuine BMW, never have ever had any issues. Will the aftermarket stuff work, probably, have never tried it.

I treat the cars like my wife, would I ever give her fake diamonds, and what would she say if she ever found out that I did.....and thus I always go OEM.

Very Convincing...:D

[san]

Yep. About 50k miles on the tank. Confirmed. I used the ecs kit.

http://tapatalk.imageshack.com/v2/14/11/09/b89a97d333e7ae308fd1ac821903bbaf.jpg

http://tapatalk.imageshack.com/v2/14/11/09/a9b2f9977d51a5bab5d184dab86f47a9.jpg

"No flamesuit required"

Thanks a lot for taking the time to dig up your ZHP's history... Really appreciate it...:)

[san]

Picture of the extent of coolant leak...

16436

[danewilson77]

Lol....I was hoping for something more under the engine bay.

"No flamesuit required"

[san]

This is the best pics i could get of the engine bay...

164431644416445

[san]

From what I could see, the coolant seems to be leaking from the bottom of the expansion tank (as seen from the wet patch on the pics) and trickle down from the rear side of the splash guard...
Apologize for the massive pics... :P

[danewilson77]

Probably a hairline crack in the tank....most likely.

"No flamesuit required"

[LivesNearCostco]

I think this is reasonably safe as long as...
1) Refill expansion tank with distilled water first
2) Verify serpentine belt is still on and spinning the water pump pulley
3) Watch temp gauge carefully to make sure it doesn't enter the red zone
4) Shut off car as soon as you identify leak, lose a lot of coolant, or see the temp gauge rise above middle/center--whichever comes first.

In some cases you will spot the leak as soon as you refill the expansion tank. In others, the system must be hot and pressurized to make it leak so you'll need to let it heat up some to find the leak, but you dont' want it to heat up too much.

If you're replacing the whole cooling system, which you should, then this test is optional. Unless you discover the leak is from somewhere unusual, like the base plate under the expansion tank, or one of the heater hoses.


by running the car without any coolant, i meant warming it up to see the leaks, not driving it (my bad should've been more clear) lol....

[san]

I think this is reasonably safe as long as...
1) Refill expansion tank with distilled water first
2) Verify serpentine belt is still on and spinning the water pump pulley
3) Watch temp gauge carefully to make sure it doesn't enter the red zone
4) Shut off car as soon as you identify leak, lose a lot of coolant, or see the temp gauge rise above middle/center--whichever comes first.

In some cases you will spot the leak as soon as you refill the expansion tank. In others, the system must be hot and pressurized to make it leak so you'll need to let it heat up some to find the leak, but you dont' want it to heat up too much.

If you're replacing the whole cooling system, which you should, then this test is optional. Unless you discover the leak is from somewhere unusual, like the base plate under the expansion tank, or one of the heater hoses.

Awesome... Thanks for the procedure... Although I'm gonna overhaul the cooling system, I definitely wanna know where the coolant is leaking from...

[san]

Probably a hairline crack in the tank....most likely.

"No flamesuit required"

Ya i think its definitely the Expansion tank... I just asked the previous owner and he was kind enough to reply about the cooling system... He said only the thermostat was changed at 73K miles and a hose.... So the thermostat was changed about 23k miles ago... Do u think I can ignore that and change everything else or should I change the thermostat too??

[danewilson77]

Thermo should be good for awhile unless you have the money to burn.

"No flamesuit required"

[san]

Thermo should be good for awhile unless you have the money to burn.

"No flamesuit required"

Ya, think il skip the thermostat for now and save some money...

One more question - just before ordering the parts, i realized that the level 2 overhaul kit comes only with the upper and lower radiator hoses... But not the expansion tank hoses etc.... Should I buy the cooling system hose kit as well? (minus the radiator hoses as they come with the level 2)
http://www.ecstuning.com/BMW-E46-330Ci-M54_3.0L/Search/SiteSearch/Cooling_System/ES2597228/
I'm pretty sure I have to but just making sure cause its not cheap...

[danewilson77]

That's a whole notha build brutha. Again, if you have the money, or the leak was suspected to be coming from there, go for it.

"No flamesuit required"

[danewilson77]

You need upper/lower rad hoses, temp sensor, expansion tank, and level sensor.

What's your plan for pullies snd belts?

"No flamesuit required"

[LivesNearCostco]

Agree with Dane, the other hoses should be good until at least 150,000 miles maybe more. I replaced all the skinnier hoses shown in that ECS overhaul kit (except the plastic heater inlet pipe and water pipe, which are sitting in a box in the garage waiting to go) between 150,000 and 185,000 miles. All seemed to be in decent shape and none had any signs of deterioration that I could see. If I could do it all over again, I would probably replace them around 180,000 miles just to be safe, but they looked like they could have gone to at least 200,000 miles. I would replace the other parts (ET, thermostat, water pump, main radiator hoses, coolant temp sensor, etc.) every 75K miles and replace radiator around 130K miles (that's when mine started leaking).

One of those plastic pipes on my car started leaking a little around 180K miles and it's on my list of things to replace. Just procrastinating because it require removing intake manifold.

[san]

You need upper/lower rad hoses, temp sensor, expansion tank, and level sensor.

What's your plan for pullies snd belts?

"No flamesuit required"

I thought il replace the pulley... The belts have been replaced recently, about 6k miles ago by the previous owner, so I think im good...

[san]

That's a whole notha build brutha. Again, if you have the money, or the leak was suspected to be coming from there, go for it.

"No flamesuit required"

hmmm.... guess I should make a thorough inspection and then decide...

[san]

Agree with Dane, the other hoses should be good until at least 150,000 miles maybe more. I replaced all the skinnier hoses shown in that ECS overhaul kit (except the plastic heater inlet pipe and water pipe, which are sitting in a box in the garage waiting to go) between 150,000 and 185,000 miles. All seemed to be in decent shape and none had any signs of deterioration that I could see. If I could do it all over again, I would probably replace them around 180,000 miles just to be safe, but they looked like they could have gone to at least 200,000 miles. I would replace the other parts (ET, thermostat, water pump, main radiator hoses, coolant temp sensor, etc.) every 75K miles and replace radiator around 130K miles (that's when mine started leaking).

One of those plastic pipes on my car started leaking a little around 180K miles and it's on my list of things to replace. Just procrastinating because it require removing intake manifold.

Thats a lot of useful info, thanks! I guess i could wait for the other hoses... But il check thoroughly and then decide for sure just to be safe...

[san]

I replaced the expansion tank assembly and the upper radiator hose on the weekend... Will replace the other parts soon... Thanks a lot for your help, you guys are the best...:)