|
|
SUPPORT ZPOST BY DOING YOUR TIRERACK SHOPPING FROM THIS BANNER, THANKS! |
Post Reply |
|
Thread Tools | Search this Thread |
01-22-2014, 06:57 AM | #1 |
New Member
6
Rep 11
Posts |
Mystery cooling leak? Advice needed...
I'm looking for some advice from any of my fellow z4 owners who may have had a similar cooling issue:
I drive a 2003 z4 3.0i with 110k on the clock. Every two days I get the yellow coolant light reappears and then I have to replace maybe 4oz of coolant. I regularly drive about 50mi daily (round trip), usually in stop-and-go traffic. The outdoor temperature has been around freezing or lower most days and I usually have the heater running, not "full-blast" though, just running around 72* and 50% fan. With that being the case, I began searching for potential leaks all over the cooling system. I searched both from the top of the engine and from underneath with the panel removed. No obvious spots to be seen or drip marks on any hoses/connections for the cooling system. My guess is that there is a leak somewhere hidden from view? Maybe a tiny crack just big enough for drips/steam to escape through unnoticed? I'm open to any suggestions, this has been driving me insane the past few weeks... Is my issue similar to any of your experiences? Driving in freezing weather with mysteriously disappearing coolant? |
01-22-2014, 08:52 AM | #2 |
Private First Class
3
Rep 106
Posts |
Sounds like you drive your car regularly, but if you are able, let it sit after driving with some cardboard under it. look for leaks that way. if you don't find the leaks while it's not running, keep the car running, windows down, and pump up the heat (with these frigid temps) to get the coolant circulating.
Personally, I doubt that steam/water vapor will be the only way coolant is escaping your system, so i think looking for drip evidence is the best way. |
Appreciate
0
|
01-22-2014, 11:21 AM | #3 |
My other car is on Mars
636
Rep 3,124
Posts |
If it's dripping onto someplace hot, it may evaporate before hitting the floor, but it will leave telltale crusty residue.
__________________
Warning: May contain traces of nuts.
|
Appreciate
0
|
01-22-2014, 12:08 PM | #4 |
New Member
0
Rep 13
Posts |
The thermo sensor connection and the lower radiator hose connection to the thermostat housing are a good guess. Location is near top of motor behind the cooling fan. As you drive the small leak is blown back on the motor and evaporates not leaving puddles. Remove plastic under tray and let car idle for 15 or 20 minutes. You should have puddle then either center under crank pully or drivers side under expansion tank. Best to obtain pressure test kit and use that to find the leak.
|
Appreciate
0
|
01-22-2014, 01:22 PM | #5 |
Enlisted Member
1
Rep 46
Posts |
I also drive an e85 3.0i Z4 (~105k miles) that had a coolant issue as well. Except my coolant light never came on and I decided to check out the coolant on a whim (temps were dropping quick in the winter) and I saw that I had almost NO coolant.
Turns out my radiator was cracked. It cracked on the seam where the plastic wraps around the metal on the radiator itself. This was near the expansion tank side too. So after I installed the new radiator I no longer have any coolant issues. The cracks in the plastic part of the radiator were so small, no wonder I couldn't find any obvious signs of leaks other than being low on coolant all the time.
__________________
e85 z4
|
Appreciate
0
|
01-22-2014, 01:45 PM | #6 |
Midlife Crises Racing Silent but Deadly Class
1821
Rep 5,337
Posts
Drives: 2006 MZ4C, 2021 Tesla Model 3
Join Date: Oct 2007
Location: Welcome to Jamaica have a nice day
|
When was the last time water pump was changed?
Also, does the motor oil have any "milky" residue?
__________________
Sitting on a beat-up office chair in front of a 5 year old computer in a basement floor, sipping on stale coffee watching a bunch of meaningless numbers scrolling aimlessly on a dimly lit 19” monitor.
|
Appreciate
0
|
01-22-2014, 03:36 PM | #7 |
Second Lieutenant
13
Rep 280
Posts |
|
Appreciate
0
|
01-22-2014, 04:39 PM | #8 |
Colonel
879
Rep 2,546
Posts
Drives: Z4MC-X3-35i-525i, Corrado G60
Join Date: Nov 2007
Location: MD
|
In the past, I've found hard to find coolant leaks using a black light at night. Even the smallest leak shows up pretty well. It may or may not work too well depending on the the coolant type.
|
Appreciate
0
|
01-22-2014, 04:42 PM | #9 |
Colonel
2428
Rep 2,704
Posts
Drives: Built not Bought 04 Z4 VF
Join Date: Feb 2013
Location: Kitchener Ontario Canada
|
I had a leak on my 04 3 litre and could not detect the leak.
Actually thought it was the blue petcock on the bottom of the rad area leaking ,turned out the expansion tank had a hair line crack. Have your local rad shop pressurize the system and see what shows up.
__________________
W2A Intercooled Vortech V3Si, custom ducting, Alpha N, 60# Bosch,2.62 pulley, multi port WMI, Severn Tuning(pokeybritches), Tial, magnaflow,SS race muffler, 42 design,3.91LSD, H&R, Hotchkis,ST coils,Konis, Megan camber arms, AKG SS, Nylon mounts, Poly bushings, Carbon interior, CF Aero.APEX
|
Appreciate
0
|
01-23-2014, 06:07 AM | #10 |
BMW CCA Member
29
Rep 90
Posts
Drives: '19 BMW X3 30i-'11 BMW 128i
Join Date: Oct 2009
Location: Music City area
|
dbarton62 may be on the right track. The expansion tank on my '03 had a hairline crack, which allowed coolant to slowly leak out, and then it changed form hairline to total failure. I'd start there since the cooling systems on early Z4's are notorious for eventually failing.
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|