2008 GX Air getting into cooling system. Need Help

[DRRichey]

Currently 145k on the clock.
A week after I bought it a year ago the lower radiator hose came loose while on the highway. Since fixing that issue I’ve had the thermostat replaced and two coolant changes. Had a pressure test done and confirmed the head gasket was intact. I burp the cooling system probably once every few months, but without fail we have a water rushing sound behind the dash after a few weeks go by.

Take note after burping, the rushing/sloshing noise disappears...this indicates to me it’s air getting into the system. Problem is I cannot find a leak.

Water pump, timing belt was replaced at 126k by the dealer under previous ownership.

I was also told the radiator had been replaced, but clearly whoever did it wasn’t competent enough to secure all the plumbing back on correctly.

Any ideas? Thoughts? Trying to get an idea before I have my wife take it in to my mechanic (ToyHouse inc in Tampa Fl) . I’m currently overseas

Help is appreciated!

 

[z00t3ch]

I have a Toyota Master Mechanic around the corner from me. When I suspected a bad head gasket on my F150 a year ago, he used some sort of sniffer around the radiator cap (cap removed of course) that detects combustion gasses present in the coolant. If you have a failing gasket your coolant could be getting slowly burned up in the combustion chamber while the combustion gasses are your source of air in the system. Hoping for your sake this is not the case, but I'm a realist not an idealist.

 

[DRRichey]

I have a Toyota Master Mechanic around the corner from me. When I suspected a bad head gasket on my F150 a year ago, he used some sort of sniffer around the radiator cap (cap removed of course) that detects combustion gasses present in the coolant. If you have a failing gasket your coolant could be getting slowly burned up in the combustion chamber while the combustion gasses are your source of air in the system. Hoping for your sake this is not the case, but I'm a realist not an idealist.

Forgot to mention they did this as well. There are plenty of visual signs as well that by now I would be able to catch if it were the case. I could be wrong but I’m guessing there’s a small leak or gap somewhere letting the air in.

 

[z00t3ch]

Forgot to mention they did this as well. There are plenty of visual signs as well that by now I would be able to catch if it were the case. I could be wrong but I’m guessing there’s a small leak or gap somewhere letting the air in.

Gotcha. Well, for air to get into a pressurized system, coolant has to be getting out. If you don't smell it or see it, it's usually happening in the combustion chamber. If it's not losing enough pressure quickly enough to cause an overheat, then it's a very small leak or the pressure is being maintained by whatever is replacing the water, and compressed gases fit the bill. If the sniff test didn't detect anything, then I understand your frustration!

 

[DRRichey]

Gotcha. Well, for air to get into a pressurized system, coolant has to be getting out. If you don't smell it or see it, it's usually happening in the combustion chamber. If it's not losing enough pressure quickly enough to cause an overheat, then it's a very small leak or the pressure is being maintained by whatever is replacing the water, and compressed gases fit the bill. If the sniff test didn't detect anything, then I understand your frustration!

I do smell coolant but I often attributed it to me burping it so often and having spilled coolant some of those times ....now the search begins ....

 

[z00t3ch]

I do smell coolant but I often attributed it to me burping it so often and having spilled coolant some of those times ....now the search begins ....

Investigating a similar issue on a customer's 2002 Escalade, seems the coolant from a failing water pump's weephole collects on the skid plate so owners never see the leakage on the ground, but occasionally get a whiff. Lots of "stuff" under a GX, too...