Mysterious case of disappearing coolant

[sailnaked6842]

Hey guys, sorry about the wall of text but I'm having some difficulty finding a coolant leak on my 6 that I literally just put a new built engine in about a month ago, which I built up from a shortblock. Currently the car is driveable but I may have nearly killed it. The story is as follows... Got the engine in the car about a month ago, put as much coolant in the car through the coolant return hose as it would take to fill the block, filled the radiator and reservoir, drove it around and all was good. Lasted about a week and then it started making gurgling noises when it was turned off even though the reservoir was full. Monitored coolant temps and one day it shot up to the 230's and I parked it. No coolant in the reservoir, took roughly 2 and a half quarts. Figured there was a part of it that didn't get full and drove it around, business as usual. Flash forward to yesterday, driving home from work I plug in the AP after driving like an asshole for a little bit to check temps and coolant is fucking 240 degrees. Fuck. Baby it home trying to keep it in the 220's, but occasionally it spikes to ~237. Buy new thermostat because I'd kept an eye on the coolant level in the reservoir and it hadn't budged. Open the hood after getting the thermostat...and there's no coolant in the reservoir. Not even a low coolant light on the dash. Took about 3 quarts yesterday. So, in 500 miles, this thing has burned a bit over a gallon of coolant and as far as I can tell there's no coolant on the garage. Only thing I can think of is head gasket or turbo. If there's other options I'm open to hear, but if that's what it sounds like, anyone know how to test them? And haven't drained the oil yet since it's the break in oil, however it will be out this afternoon since there's about 20 miles left for the oil. Worst part about all this...drove the car today...it feels sluggish and doesn't seem like it's making boost as easily...fuck.

[sheston]

If it is leaking, you should be able to take the plastic tray off the bottom and see that amount. Folks have had problems finding leaks in the past, because the tray catches it fairly well, but empties at speed.

If the motor was burning it, seems you would see some white smoke. I'm going with something not connected good enough when replacing the new block.

Good luck finding it. Hope you fix it before damage occurs

[sailnaked6842]

Thanks, it's easier knowing that there is an issue now so that I can keep track of it, ya know? On the other hand it's drinking coolant almost as fast as the gas that goes through it, 3/4 gallon of coolant for 80 miles worth of driving. Dried the reservoir and had a bunch out of the radiator.

Getting to the meat of the issue though, I'm assuming you're talking about the tray under the radiator, which is the skid plate? The car, unfortunately, doesn't have one lol and no drips around the bottom of the radiator. Top of the engine is dry as well. For the sake of not ruling anything out I did a a compression test and it came out well (165, 170, 171 and 172), also I put 30 psi into the cylinders to see if there's leaking past the head gasket and it seems to be okay, as far as I can tell. Didn't think it was relevant but there is white smoke at start up but it seems to clear up after it warms up, it's slightly more than normal, but nothing you'd see and get alarmed about.

Also, for anyone who sees ECT temps at that level, chances are you'll be fine, it was just a different pair of shoes

[allservice]

Well, I am facing a similar problem. Have you find the cause of the coolant leak in your car?

[Jeff23spl]

pressurize your radiator, there is some pump that can connect at the place of the filling radiator cap and you should quickly see where it leaks....

Or make a temporary cardboard engine tray to see if some fluid can be going to the ground while driving and you don't see it.

It could be a cracked hose, a clamp not tightened properly....a rotten transfert hose etc...I had issues with the one between TB and just at the end of the TIH. I had a factory battery but a flexible 3'' TIH that force that small hose to cut against the elbow. it was leaking just a little and wasn't seen anywhere unless i remove some parts....