Coolant Dripping 2007 Tacoma V6 (Solved)

Hello,

I refilled my coolant several weeks ago. Today, I just checked my engine as I usually do and discovered that there was coolant inside the reservoir dripping downward.

Idk what caused this. Could anybody give me a hint? I see my coolant level is at the max level when engine is running at the time taking these photos. Should the coolant level in the reservoir be under the max level when engine is on or I overfilled it? Thank you guys

 

Filling over the max line should not have caused that leak. Now that the level is at the max line, has it leaked? My guess is the reservoir may have a crack or the hose has lost its sealing capabilities.

 

There’s a few possibilities. Radiator cap leaking. Hose from the radiator neck to the reservoir leaking. Reservoir is cracked. Reservoir tube inside is clogged. Give it all a good cleaning, then try to catch it before it gets that bad.

For your missing round trim clip things, I picked up a pack of them from Napa, as suggested by another member. I can’t find the picture or baggie it came in right now.

 

Coolant gets sucked into radiator on startup if needed and dumped back in as it expands.
Is the rubber hose fairly tight on the reservoir as looks like that's where it dumped/came out.
If loose cut a 1/2" off and that should be tight then. My 09 never had spring clips on that hose just looked to verify. No cracks at hose entry point is there.
The rad cap should have been changed at some point also with similar pressure marked on cap as 108kPa.
Max line is when hot and rad full. If the truck was overheating temp would show it and res would be overfull and dumping out that overflow by black fill cap.

 

Mine kinda looks like that every once in a while. not as bad, but close. I always assumed it was that little hose but never did anything about it. I wouldn't worry too much. My engine hasnt overheated or even hiccupped....at 205k on the odo.

 

I don't see any dripping coolant on the ground when my truck is parked so I’d assume no leak. This overflowed coolant near the reservoir is the only thing I see for now.

 

Looks like it's either leaking where the hose connects to the reservoir or the reservoir is cracked.

The reservoir is part of the fan shroud should it need to be replaced.

 

Here it is. Looks like it was a 6 pack, dirt cheap & works the same.

 

I think I found the leak. It’s from the hose connecting to the reservoir. I turned on my engine for 30 mins and turned it off. As soon as I turned it off, I looked at the reservoir, I saw it was wetting right between at the reservoir and the hose. As I was trying to turn the hose and it was just a little loose, so will try to replace that hose. Anybody the size for that hose?

 

The rubber hose is just a little loose. Is it supposed to be loose or tighten?

 

It shouldn't be loose, it should fit snug.
If the hose is not split you can put a zip tie or small hose clamp on it and likely solve your issue, if the hose is split replace it.

 

It almost looks like there may be a small crack in the reservoir inline with the tube the hose attaches to, I'd clean all the crusties off and look at it closely.

 

You do not fill the coolant through the overflow reservoir.
You fill it through the radiator cap, when it is cold. I have used factory methods of vacuum filling. I have also done gravity fill with special tool and front end raised on ramps. Usually cold, filling it, starting it up, and running the heater on to open heater core pathways.

Overflow is there to contain overflow as the coolant expands and contracts.
It, and plastic, can crack, but tends to less on Toyota.

Rubbers and plastics on Toyota are designed with a better formulation than German cars, run at a lower temperature with more cooling, and last longer.

However, over time, that rubber hose can dry, and will conform to the nipple sealing surface.
It will conform so much, that it will no longer have an original tight squeeze fit.
The solution to that is literally to take it off, possibly clean it if you want, then re-install.
R&R means remove and re-install. The fix is to do that.
Remove will let it shrink back down, then squeeze again as you re-install.
That is quick to do. You can also lube it.

It is up to you, if you want to add "Part Replace" to R&R. Which is how it's typically done other brand cars, earlier, because their parts do not last as long.
Their parts will usually have a symptom of failure, actually be failed, and need replacing. To the point where simply removing and re-installing will not fix it.

This happens with the Tacoma power steering line(s) as well, likely the low pressure line. It leaks in a similar way, then people R&R it to stop the leak.
I could, but at this point given the age and miles of such components on the truck, if I'm in the area spending my labor time to work on it, I'm gonna throw a new part in while I'm at it for peace of mind. 0 mile new part can have more life in it.
Especially considering how cheap they tend to be on these trucks, and ease of installation.

Maybe it is cracked. The typical way to test cooling cracks is a pressure tester.
But if you are in doubt, it is not that hard or expensive to say fuck it, chuck a part at it, and throw new nice looking reservoir in there.

 

My 07 manual says to add coolant via the reservoir if it is dry. If the reservoir is cracked, JB Weld it before buying a new one cause it comes as one piece with the shroud.

 

I do not know if there is a hidden pathway connecting the overflow to the radiator.
I doubt it does.

It is likely what it's commonly referred to, an overflow. I believe the tube into it, goes down like a straw, giving the ability to suck fluid up in the event of cooled contraction.
Autozone is even calling it a recovery tank.

The radiator has a cap for a reason. That both vacuum fill tools, and gravity fill tools, are designed to screw into.

Historically, people add coolant to a radiator.
It's only when other brands (German) came out with no rad cap/deleted, and only reservoir that feeds directly in, that coolant is added there.

There is no harm adding directly to the radiator when it is cold.

Pictures do not show some sort of secret hidden passageway behind it.



Not the same as a German car having coolant tank central in the engine bay, many including large hoses going to it, routed to places like thermostat, radiator, etc.

 

I'd bet money the neck on the reservoir tube is cracked and possibly the reservoir itself is cracked also. 16 years of heat to plastic will do that and where the tube neck attaches is pretty vulnerable to begin with. I wouldn't bother with trying to patch or repair it, I'd recommend replacement.

 

It looks like a formed hose you’ll need to source from the dealership. That doesn’t mean you have to use the formed hose. You could use standard coolant hose but it might end up rubbing against the hood.

You could possibly have more than 1 leak. Leaks, similar to electricity, take the path of least resistance. For example, you have 1 psi, 5 psi, 10 psi leaks. You fix the 1 psi leak, then the 5 psi leak will reveal itself. Fix that one, then the 10 psi leak will reveal.

Excluding the recovery portion, a coolant pressure tester will normally show all leaks unless the leak is so bad it won’t pressurize.

When it’s a customer vehicle, I’ll say I’ll fix this leak, clean it up, then test to see if anything else is leaking. What sucks is when a $5 hose leaks at 1 psi and the radiator leaks at 10 psi.

 

yeah. You fill through the radiator. Then as the picture states, inspect overflow level when cold and verify or adjust to full.
This means the cooling system in the truck and radiator is already also full before that. You are just adding more.

the overflow provides a catch for overflow, and a little bit of coolant to go back into the radiator in the event of cold temperature contraction, or leak, as well as way to notice if there is a leak or not if seeing the level decrease.

it is small. During a complete replacement it would not have room to fill the cooling system, nor the pressure to.

this is not new.

 

I’ve always filled through the radiator when replacing the coolant, but for topping off the reservoir, as is the case at hand, top off through the reservoir, that’s why it has a cap. Besides, you cannot get coolant to the reservoir max line by adding coolant to the radiator, you have to put it through the reservoir cap.