Coolant drop 1/5 in 20 days...

[jamesq]

Right after the new year I found the anti-freeze reservoir already empty.. So I bought zerex from amazon right after on Jan 16 and refill it to F mark when car is cold. Today I did another check when car is cold. The coolant dropped about 1/5 from F to L mark. After the refill I drove around 200 miles only. I don't think this is the normal speed that 4Runner drinking coolant. Any thoughts from you guys?

ps: I didn't see any sign of leak after a long time park, neither did I notice any red fluid around engine.

 

[delloro]

Right after the new year I found the anti-freeze reservoir already empty.. So I bought zerex from amazon right after on Jan 16 and refill it to F mark when car is cold. Today I did another check when car is cold. The coolant dropped about 1/5 from F to L mark. After the refill I drove around 200 miles only. I don't think this is the normal speed that 4Runner drinking coolant. Any thoughts from you guys?

ps: I didn't see any sign of leak after a long time park, neither did I notice any red fluid around engine.

Pressure test. If you have a radiator shop in town they can do it. Otherwise rent or buy the tool. O'Reilly auto parts has loaner tools.

 

[rigtec]

Right after the new year I found the anti-freeze reservoir already empty.. So I bought zerex from amazon right after on Jan 16 and refill it to F mark when car is cold. Today I did another check when car is cold. The coolant dropped about 1/5 from F to L mark. After the refill I drove around 200 miles only. I don't think this is the normal speed that 4Runner drinking coolant. Any thoughts from you guys?

ps: I didn't see any sign of leak after a long time park, neither did I notice any red fluid around engine.

Hi James,

The F stands for full, and the L means Low. The plastic bottle is a expansion tank to allow for the coolant to expand when the engine has reached it's full operating temperature. In this cold weather we should be topping the bottle off at L (Low) so the coolant has room to expand when the engine reaches it's full operating temp. If you're topping it off at F when the engine is still cold then you're creating a condition that would certainly cause a pipe or tubing to burst if not for the safety cap and overflow port once the engine reached it's full temperature...

there's a good chance that the coolant is using the overflow when the engine reaches 12-15 PSI as it has nowhere else to go! Try this... when the engine is cold (30 Deg or so) level it off at the L mark and then check it again after 20-25 mins of driving; my guess is that the level will be around the 'F' mark. After the vehicle cools down to ambient temp, you may find the coolant level has gone back down to the 'L' mark again. Let us know the result of your test; I'm sure you're not the first to experience this,

rig, Cheers!

 

[jamesq]

Hi James,

The F stands for full, and the L means Low. The plastic bottle is a expansion tank to allow for the coolant to expand when the engine has reached it's full operating temperature. In this cold weather we should be topping the bottle off at L (Low) so the coolant has room to expand when the engine reaches it's full operating temp. If you're topping it off at F when the engine is still cold then you're creating a condition that would certainly cause a pipe or tubing to burst if not for the safety cap and overflow port once the engine reached it's full temperature...

there's a good chance that the coolant is using the overflow when the engine reaches 12-15 Deg F as it has nowhere else to go! Try this... when the engine is cold (30 Deg or so) level it off at the L mark and then check it again after 20-25 mins of driving; my guess is that the level will be around the 'F' mark. After the vehicle cools down to ambient temp, you may find the coolant level has gone back down to the 'L' mark again. Let us know the result of your test; I'm sure you're not the first to experience this,

rig, Cheers!

Thanks for the input. I saw this on manual p503: "The coolant level is satisfactory if it is between the “F” and “L” lines on the reservoir when the engine is cold."
So I think refill to F line when engine is cold is acceptable. I just don't know where the missing fluid go? Burned?

 

[flyrv9]

Check your oil. If oil looks normal and the level is normal, you could have a pin hole in a hose. If oil level is high and / or looks funny - you could have a blown head gasket.

 

[catrains]

Right after the new year I found the anti-freeze reservoir already empty.. So I bought zerex from amazon right after on Jan 16 and refill it to F mark when car is cold. Today I did another check when car is cold. The coolant dropped about 1/5 from F to L mark. After the refill I drove around 200 miles only. I don't think this is the normal speed that 4Runner drinking coolant. Any thoughts from you guys?

ps: I didn't see any sign of leak after a long time park, neither did I notice any red fluid around engine.

pressure testing is good to determine if you have a leak................
however to find a leak exactly you add dye to the coolant. like UV DYE..

now in the dark you use a UV flash light and see where its leaking.

most times on an engine the leak is from the water pump when you cannot find its location. the coolant leaks out as the engine heats up and the pressure rises.

if you added any drinking water or other non distilled water this can be the reason its with a leak. not sure on a 2012 if your using the correct coolant. I have not found a substitute for Toyota coolant after searching for my 2016 T4R. coolant must be 50% antifreeze or more. if less % then corrosion and leaks water pump damage.