So this problem has been pissing me off for the longest time. Every 3 or four days my car looses about a gallon of coolant. No signs of leaks, etc. I have a gallon of coolant and the rest is tap water in the system. I bleed the system and 4-5 days later the waterfall sound is back. I have no idea whats going on, the car doesn't overheat, no white smoke, no milky oil, no milky coolant. The car has MHG and ARP head studs. I'm at my whits end. All replies are appreciated.
Huge amounts of coolant loss
- Thread starter iDriftYou
- Start date
If it's not leaking on the ground or in your car anywhere then your engine is eating it. Hate to say it but look for signes of BHG. Possibly it could be leaking slowly on your exhaust mani and boiling off before it hits the ground I suppose but you'd hearlsee that. Check all your lines and make sure you don't see any residue on them etc.
Put the cooling system under pressure with a pressure test kit. You see it dropping you know there's a leak, just a matter of finding the trickle of coolant/water. If you can't find it, see if the engine is harder to start or stumbles when starting after keeping pressure on for half an hour (keep pumping it up as it loses pressure). That's a pretty good sign that your leaking in to your cylinder. You can also pull your plugs and look for coolant sitting on top of pistons and/or washed plugs/pistons with a pen light.
On the flip side, it could be leaking past a hose only when it's at operating temperature. Take a listen for any hissing/dripping when you turn the engine off after a good hot drive. I had the coolant hose at the back of the head leaking a tiny bit once that never showed any drops because it was disappearing before it could hit the ground, and only leaked when hot.
Also, OfnaRcR4....I find it funny that your avatar has 18psi of boost with the low coolant light on in a thread like this :yelrotflm Made me chuckle...
On the flip side, it could be leaking past a hose only when it's at operating temperature. Take a listen for any hissing/dripping when you turn the engine off after a good hot drive. I had the coolant hose at the back of the head leaking a tiny bit once that never showed any drops because it was disappearing before it could hit the ground, and only leaked when hot.
Also, OfnaRcR4....I find it funny that your avatar has 18psi of boost with the low coolant light on in a thread like this :yelrotflm Made me chuckle...
Had relatively the same problem with my car. I would have to add coolant every 4-5 days but not a gallon though. Turned out my thermostat housing was leaking ever so slightly and had to be rebuilt. Check that maybe?
He likes to go big or go home.radiod;1774839 said:
At the OP: Pressure test. Also pressure test your cap. I literally had 4 caps go bad on me this summer, one was bad out of the box. I've seen that overlooked many times, the system holds pressure with the tester on, but with the cap on it will leak because the cap itself is bad. Is your overflow tank full?
-AM3
Another MkIII;1775089 said:
that was my issue. the rubber on the cap was missing so once it tried to presurize it would puke out. also did you replace the elbows of death yet? though could be peeing on the manifold
Exactly. The float in my reservoir doesn't float so I'm always low hah.Another MkIII;1775089 said:
Another MkIII;1775089 said:
yes the overflow is always full. this what ive noticed, if I drive the car for less that an hour the water is always full but when I make 100 mile trips I lose about a gallon of coolant. what gives?
PS-my radiator is a mizu aluminum 3 row which is maybe 4 months old and has a 16psi mizu cap on it.
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My leak is coming from the rubber hose at the back/passenger side of the head. It took me forever to find it because the heat from the manifold was evaporating the coolant. I'd check there, it's happened to me twice now.
Then you have no leak and your coolant has found a way to teleport out of the system. Get a pressure tester, and test the system properly, not with a redneck hose squeeze. If you aren't going to take our advice, we can't/won't help you.iDriftYou;1776506 said:
-AM3
mine did the same thing
BHG...drove for 8 months 500 miles a week likes this(yes i know dumb idea but i planned on full rebuild and in the process of rebuild now)
just had to keep adding water
well finally is blew completely lol
is the area around your overflow resevior rusty in color? if so then exhaust gasses are entering your cooling system
overpressurizing and blowing coolant out overflow resevior
BHG...drove for 8 months 500 miles a week likes this(yes i know dumb idea but i planned on full rebuild and in the process of rebuild now)
just had to keep adding water
well finally is blew completely lol
is the area around your overflow resevior rusty in color? if so then exhaust gasses are entering your cooling system
overpressurizing and blowing coolant out overflow resevior
weird... My overflow tank leaks coolant. but the cap is cracked badly.. lol.. you guys think it might be just the cap?
iDriftYou;1776506 said:
Only reason its hard as a rock is because your loss of coolant, which = overheating. even after hard driving my upper rad hose never gets hard. A hard upper rad hose is a sign over overheating. better watch out...