Coolant smell

[nkostop]

Hi I have been smelling coolant lately on my 01 Tahoe 5.3. It doesn't overheat or run odd as if there is a head gasket problem. But I really don't know how to figure out where it's coming from because there is no leaks, that is that I can see. Any support would be great

 

[#1taho]

Check the bottom of you water pump. Sometimes you can smell it before seeing it. Do you mainly smell it inside of out side?

 

[nkostop]

Outside, can't smell it when in the truck

 

[#1taho]

check water pump

 

[retiredsparky]

If you have the optional rear heat, there is a set of tee fittings in the heater hoses above the motor at the firewall. For some reason GM decided that o-rings were a good way to make that connection. (Not!) I bet that there are a lot of high mileage trucks with this option that leak (the leak takes a long time to get bad, it just drips enough to smell).

 

[retiredsparky]

Aluminum heads can have small cracks in them over time. Steam ports weeping on the back side of the engine where they are not visible.

 

[06Escalade]

If you have the optional rear heat, there is a set of tee fittings in the heater hoses above the motor at the firewall. For some reason GM decided that o-rings were a good way to make that connection. (Not!) I bet that there are a lot of high mileage trucks with this option that leak (the leak takes a long time to get bad, it just drips enough to smell).

I just replaced both for this issue. Smelled when using the heat. Because the vent is right above. The way they are situated think I messed them up cramming my hand down there to change the plugs... And every time I remove the plastic cover they get flexed. But they were pretty brittle after years of heat and dexcool. Now I have no rear heat. Hoping its an air bubble but its been a few days now.

 

[savagebasher]

I just replaced both for this issue. Smelled when using the heat. Because the vent is right above. The way they are situated think I messed them up cramming my hand down there to change the plugs... And every time I remove the plastic cover they get flexed. But they were pretty brittle after years of heat and dexcool. Now I have no rear heat. Hoping its an air bubble but its been a few days now.

Bump... I think I have the same issue.. do you guys replace the rings only or the entire tee fitting? Part numbers?

 

[OR VietVet]

If you only smell it when outside the vehicle and I bet you are standing at the front when you do, then I agree that it is likely the water pump weep hole. It will be on the bottom of the case and can be seen with a mirror and a flashlight, with the help of a pressure test kit. When you do the water pump, if that is it, change the thermostat as well. After filling and pressure test to make sure there is no pressure loss, take for a quick road test and recheck the coolant level. Check the coolant level for the next 2-3 days to make sure you get any air pockets out of the system.

 

[nkostop]

UPDATE: There was a coupling fitting on one of the heater core lines that was leaking onto the manifolds, $4 part fixed it.