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Hummer H3For the Hummer driver who wants the rugged look and off road capabilities of the Hummer, but in a smaller size and with a more fuel economy friendly engine.
In all seriousness, DEXCOOL doesn't evaporate under sealed conditions. The overflow tank is far from being sealed. Cap is just friction fit and there's an overflow hose that vents to atmosphere. Or is there a one way valve or something on the vent hose?
Just for chits and giggles, I filled a water bottle with some DEXCOOL, poked a small hole in the cap, attached a breather hose and placed it into a hot azz shed. Let's see just how much water loss we get over the next few weeks.
Starting weight 175.86g
Last edited by MadDogBimmer89; Jun 21, 2024 at 08:13 PM.
My 2010 has been had a mysterious coolant loss since I got it 12 years ago. Had all kinds of checks and inspections. I just top it off once-in-a while. Got some GM stop-leak tablets that help a lot. I don't like it because it is not right, but nothing else I can do, so I drive on.
In all seriousness, DEXCOOL doesn't evaporate under sealed conditions. The overflow tank is far from being sealed. Cap is just friction fit and there's an overflow hose that vents to atmosphere. Or is there a one way valve or something on the vent hose?
Just for chits and giggles, I filled a water bottle with some DEXCOOL, poked a small hole in the cap, attached a breather hose and placed it into a hot azz shed. Let's see just how much water loss we get over the next few weeks.
Starting weight 175.86g
The coolant reservoir is designed to prevent evaporation. The outlet hose is there to allow the reservoir to suck air back in to refill the coolant in the engine when it cools down. I just took another pic from a different angle, currently 96°F ambient, and you can see the outlet is elbowed high above the reservoir preventing any coolant loss, yet there's condensation under the cap that will fall back in:
So after several weeks of monitoring turns out it was leaking from the heater hose disconnect. It started as a very small leak, apparently small enough to hold 15psi, but got worse overtime. Question is, does coolant always circulate thorough the heater core or only when using the heater?
Needles to say I cut the quick disconnect off and just slid the hose over the core inlet/outlet pipe, threw gear clamps on and called it a day
