Antifreeze leak overnight? No puddle

[RabbaniE34]

I haven't found a thread on this. My car seems to be leaking anti freeze over night. I filled it up last night to the max line. Today it seemed like it went down like 3 lines. I filled it up when the car hasn't been started (COLD) as im aware the amount reads differently when the car is running. There is no puddle underneath and it doesn't look like its leaking within the hoses. The car seemed to have an overheating issue when at idle. Im working on the car right now finishing up on some odds and ends. I started it up yesterday ran it for like 10 mins and the cars temp gauge is passed the middle line. Ive been driving the car for over a year. Always needed to check on the anti freeze to make sure it was full. A mechanic told me theres nothing wrong with my cooling system which i think is bs. Any suggestions on what to look for?

[S61Dan]

The level is different if the engine is warm. Let it sit overnight or so, then check it. Any white smoke coming out of the exhaust? Any smell of coolant when you turn on your blower motor? How far past the middle line? Like, less then a needle width or so? If you are constantly having to add some over a year of driving, it is probably eating it.

[RabbaniE34]

No white smoke from the exhaust. I checked the oil no signs of mixture of antifreeze in there, nor does the antifreeze itself look dirty. It doesnt smell like coolant when i run the blow motor .. It was about 3 lines down from the max line which i filled last night and didnt drive the car since i filled it.. Just ran the engine for about 10 mins until it started getting a little too hot

[S61Dan]

If the engine is getting too hot, you have some investigating to do. If you have a leaking headgasket, sometimes you can't tell that they are mixing by looking at it, you will have the symptoms that you are seeing, the overheating, the missing coolant etc. but since your loosing coolant when you check it COLD and you are checking it a day or whatever later and you haven't driven or started it and it is down then you obviously have a leak somewhere. When was the last time you replaced any cooling related items? The thermostat, radiator, fan clutch, water pump. These items obviously when worn will cause the car to overheat, but not necessarily make coolant go missing. It sounds like you have two problems

[RabbaniE34]

Ran the car again today to double check if there are any leaks. I shut it off after the temp gauge passed the middle line. I noticed there was a little puddle of anti freeze under the car. So yes there is a leak. The heat isnt working either when i tried to blast it. So i may have ran into other mechanical issues. Ive read up on heat not working and its relationship with the car overheating. Can you give me your feedback on it, if any?

[E38740iMD]

I see you own a m20. Check behind the block for a leak of some sorts

[Sleepyhead97]

Buy or rent a coolant pressure tester. Save you a big headache

[RabbaniE34]

Will do. Ill follow up when the work is done. Thanks for the help all

[RabbaniE34]

Hi guys, figured to follow up on this. So i got the water pump and thermostat replaced. That fixed the overheating issue. Im still obliged to add coolant because im losing a substantial amount every few days. I drive on the highway about 8 miles each way from and to work. There are no signs of any leaks from underneath the car. No leaks in the carpet. No white smoke coming out of the exhaust. No smell of coolant coming through the blow motor. Checked the oil, no signs of mixture (Milky color). My spark plugs were checked from my mechanic, and i saw them myself as well; He explained their would be white residue if the gasket was bad. Also, he ran some sort of compression test through the coolant reserve and claims the car isnt losing pressure. Any suggestions? Any other symptoms or indications im missing that would be a signal that im loosing coolant internally?

[Binjammin]

Check your tranny fluid?

[RabbaniE34]

For Mixture?

[Binjammin]

For Mixture?

If you have an automatic transmission, the tranny cooler is built into the radiator.

[RabbaniE34]

Ok and what am i looking for exactly? Possible bad tranny cooler?

[Binjammin]

Ok and what am i looking for exactly? Possible bad tranny cooler?

Automatic transmission fluid is candy red in color. When it gets old it looks somewhat like old engine oil. If you mix coolant with new atf it will appear milky pink like strawberry milk. If you mix coolant with old atf it will look like chocolate milk. If you're loosing coolant into your transmission the transmission will likely be well over the fill mark.

[RabbaniE34]

I topped off the expansion tank today and drove the car a pretty decent distance on the highway and back. I pulled into a gas station to get gas and check my coolant levels. I see a leak from what looks like the bottom of the expansion tank. I could be losing coolant there.

[BoldUlysses]

My old M50 525 would periodically "burp" coolant, especially when the weather turned cold. Car ran perfectly and there was no evidence of leaks. I was stumped, but it only happened 2 or 3 times during my 3 years of ownership so I just topped it up and moved on.

I eventually developed this crazy theory that coolant would leak from the expansion tank somewhere and collect in the U-shaped crossmember underneath the radiator (hence no drips) and that the car's movement from the act of driving would slosh it around enough to evacuate most of it from of the crossmember. Never confirmed or denied the theory but it seemed to fit the facts.

[RabbaniE34]

Your "crazy theory" is exactly what i think im experiencing. I pulled into the has station to check my coolant. And it was getting caught on that U-shaped crossmember underneath the radiator. I was lucky enough to see some dripping on the floor some how so indicate leak. I took a better look at it. It looked like there was some dry anti freeze there as well. I really hope i found the problem, ive been under the impression theres some mysterious head gasket issue with no evident indications.

[5mall5nail5]

Check the carpet. If your heater core is leaking it might be wet down by the passenger/drivers feet. No coolant on the ground.

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My old M50 525 would periodically "burp" coolant, especially when the weather turned cold. Car ran perfectly and there was no evidence of leaks. I was stumped, but it only happened 2 or 3 times during my 3 years of ownership so I just topped it up and moved on.

I eventually developed this crazy theory that coolant would leak from the expansion tank somewhere and collect in the U-shaped crossmember underneath the radiator (hence no drips) and that the car's movement from the act of driving would slosh it around enough to evacuate most of it from of the crossmember. Never confirmed or denied the theory but it seemed to fit the facts.

Good theory except there are holes in that U-shaped tie that leaks coolant very easily.

[RabbaniE34]

Carpet is not wet at all. I know for sure its not leaking from the heater core. Can it be simply evaporating from the cap of the expansion tank?

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Ive honestly troubleshooted all the possibilities of it being a head gasket issue. If ive missed anything let me know! At this point i think its something im totally overlooking

[BoldUlysses]

Pic I took when I did a rad replacement in Jan of 2012:

http://www.boldulysses.com/cars/e34/radchannel.jpg

The antifreeze in the crossmember is residual from the act of draining the radiator. Still, it illustrates that the crossmember can hold some liquid. Is that enough to account for the loss without overflowing and dripping? I don't know. But again, it fits the facts. What's that Arthur Conan Doyle quote again...? ;)

[Binjammin]

What's that Arthur Conan Doyle quote again...? ;)

"It is a capital mistake to theorize before one has data." ?

[BoldUlysses]

:rofl

I was thinking more of:

"When you have eliminated the impossible, whatever remains, however improbable, must be the truth."

[Binjammin]

:rofl

I was thinking more of:

"When you have eliminated the impossible, whatever remains, however improbable, must be the truth."


Uhm.... isn't that just Occam's Razor? It's only a few thousand years old. :dunno

[BoldUlysses]

William of Ockham; c. 1287 – 1347

~650 years?

Ockham razor states that everything else being equal, the simplest solution is the most probable. It assumes you've already eliminated the impossible.

[5mall5nail5]

Yes the channel will hold coolant, but nothing substantial. That's likely an ounce or so. Anything that forms even the slightest coverage of the whole area dribbles out of the holes in the bottom of the channel (which is likely why they're there).

[Binjammin]

William of Ockham; c. 1287 – 1347

~650 years?

Ockham razor states that everything else being equal, the simplest solution is the most probable. It assumes you've already eliminated the impossible.

Potato, potato. According to wikipedia he stole it from Aristotle. Even 2000 years ago, the forums were telling newbs to stfu.

[SW530]

William of Ockham; c. 1287 – 1347

~650 years?

Ockham razor states that everything else being equal, the simplest solution is the most probable. It assumes you've already eliminated the impossible.

This is a classic mistake in interpretation when interpreted to English.. Ockham's Razor correctly stays that which you draw the fewer assumptions from.. is most likely the correct answer. Close but so far away when you stop and think about it.