Is this normal?

[cloudrunner]

Last weekend I noticed that my coolant reservoir was near empty. I went down to the Toyota dealership on Sunday and bought some coolant to refill the reservoir. There are no apparent leaks in the radiator, but I did notice this small trickle in a line next to the reservoir. [MENTION=66389]BlackWorksInc[/MENTION] would you mind taking a look at this picture to give your diagnosis?

 

[AZ07Runner]

Judging by its location, I'd say the leak is coming from under the coolant hose with green stripe. Hose or radiator neck issue...hopefully just the hose.

 

[cloudrunner]

Nope checked under the hose and it is perfectly dry. Are these hard lines for the A/C refrigerant and could it just be condensation coming off of the lines? I noticed the drips only come when the A/C is on. You'll notice the line in the foreground also has some fluid around it as well. Doesn't smell like coolant.

 

[pushinlexus]

Yes that is not a coolant leak, that line gets really cold and create condensation which could drip.

 

[BlackWorksInc]

That air conditioning line will get very cold, with how humid it is in Florida you'll see a lot of condensation on the low pressure lines forming.

As for the coolant mysteriously dissapearing with no signs of a leak, how crusty does the radiator cap look? I could be going bad and letting the coolant boil off.

 

[cloudrunner]

That air conditioning line will get very cold, with how humid it is in Florida you'll see a lot of condensation on the low pressure lines forming.

As for the coolant mysteriously dissapearing with no signs of a leak, how crusty does the radiator cap look? I could be going bad and letting the coolant boil off.

Here is a picture of my radiator cap. Doesn't look crusty at all.

 

[emoore924]

Coolant disappearing is not normal.

Sometimes coolant leaks are a little hard to find because the coolant evaporates before it drips. So, best case for you, a coolant hose has a pinhole or is weeping at a clamp, or you have a pinhole in the radiator or something. Look for yellow-whiteish powdery residue on the backside of the radiator or on the bottom side of a coolant hose.

Alternatively, there might be an internal leak in the engine - head, head gasket, block. That would typically require a pressure test of the coolant system to properly diagnose but often can be found by looking for water in the oil (pull dipstick or oil fill cap looking for milky goo), oil in the water (look on the backside of your radiator cap, looks reasonably clean in the pic) or combustion in the cooling system (bubbles out the radiator neck when the engine is running)...

 

[CruzadoBlanco]

if its a V8 it could be weeping out of the water pump, which is under the timing cover so you cant see it till you pull the front of the motor apart. its what im going with for the cause of my slow disappearance of coolant

 

[cloudrunner]

Thank you gents. I have the V6. I glanced over the radiator and hoses already and no signs of a leak. I will check the radiator a little more closely this weekend. I also pulled the dip stick, oil seems normal. It's a mystery for now...

 

[earthrealm]

A Pals 06 truck is experiencing this same issue.
advised him to swap the radiator cover, and then the big black radiator hose, since he claims he cant see any leakage after inspecting the car.

do let me know how yours ends

 

[asdfman7]

if its a V8 it could be weeping out of the water pump, which is under the timing cover so you cant see it till you pull the front of the motor apart. its what im going with for the cause of my slow disappearance of coolant

Could happen on a V6, too.

Drop the front skit plate, crawl under the front and look up at the bottom of the water pump. Also, get an inspection mirror and look inside the back of the pulley bolted to the water pump. My leak was evaporating before dripping down. I didn't notice it until I took the pulley off when sealing the front timing cover.

 

[morphious]

Mileage? Less likely a HG issue since yours appears to be 06+, but still possible.

 

[cloudrunner]

Mileage? Less likely a HG issue since yours appears to be 06+, but still possible.

-138,000. This is the first issue I've had. Runs like the day I bought it.

 

[Counterpoint08]

OP, what year is your 4Runner? Your mileage is typical of the appearance of HG problems in the 05 and earlier 4th gen v6s, but some of the 06's with early build dates also can have HG problems, but no reason to jump to conclusions with no other symptoms. Also, is it just me but in the pic your coolant doesn't look very "pink". In fact it kind of has a rusty color? When was the last time the coolant was changed?

 

[cloudrunner]

OP, what year is your 4Runner? Your mileage is typical of the appearance of HG problems in the 05 and earlier 4th gen v6s, but some of the 06's with early build dates also can have HG problems, but no reason to jump to conclusions with no other symptoms. Also, is it just me but in the pic your coolant doesn't look very "pink". In fact it kind of has a rusty color? When was the last time the coolant was changed?

It is a 2007, so a few years after the HG debacle. I have never changed the coolant, but it is on the list along with changing the tranny fluid for sure.

 

[Counterpoint08]

Well good if it's a 2007 then it's not likely to be a HG. For the record, at 138K miles you're almost at the mileage (150K) where your coolant should have been changed TWICE by now, once by 100K then again 50K miles later according to Toyota. I would change the coolant to fresh "pink" long-life asap. You might have some corrosion in your system with that old coolant , but at the very least, if you have any leaks, or a weeping water pump, the bright pink coolant will make it easier to spot.

 

[cloudrunner]

So, it has been a few weeks and the coolant reservoir is still at the full line. It appears that the mysterious leak has somehow fixed itself! To be sure, I dropped it off today at Central Florida Toyota and had a tech take a look at the radiator, hoses, under the water pump, etc. He could not find any signs of a leak.

Since I have never changed the coolant I had him do a full flush on the system. I also did a drain and fill on the transmission as he did not recommend a tranny flush with my mileage. I will bring it in every few month for continuous drain and fills to freshen up the tranny fluid over time, I'm thinking over the next 3 oil change intervals.

I also got some 2015 TE rims mounted up and they look awesome. Installing a Gibson catback exhaust system tomorrow!!! After a long hiatus I am moving forward with my build!