Potential Coolant Leak?

Hey Guys,

So my truck has nearly 180k on the odometer, yesterday after driving about 120 miles I noticed that my temperature gauge was rising past the normal level as I was idling in the parking lot. I thought it was strange because I had just drove for a good distance and didn't have any issues, CEL, overheating, etc. The truck runs great and I haven't noticed anything.

When I shut the truck off, I heard a gurgling noise come from the truck, and the coolant reservoir was very low. So I let the truck cool down for a few hours and I checked again. Same thing, low coolant, but the radiator had pressure when I opened the cap.

I did notice that the upper radiator hose had a wet spot directly above it connects into block. We are talking about one drop of coolant type of leak. I wasn't able to see any other leaks on either the upper or lower radiator hoses.

I don't use my truck to commute to work often, but I have only noticed the gurgling noise/rising temp gauge, but I never thought much of it because when I would go to try to recreate the problem, it wouldn't come back.

I assume that the gurgling noise is air in the system due to low coolant in the reservoir. What I am not sure about is where to look for coolant leaks aside from the small one I already found.

Is this just a matter of refilling the reservoir up to the correct level and seeing what happens? Or should I take this to the shop? I personally don't have the time or space to handle repairing this on my own.

Thanks in advance,
Tom

 

Fill the reservoir to the proper mark and keep an eye on it. The reservoir level should rise when engine is hot and drop to the correct level when engine is cold. Easy way to watch for fluid loss. Good luck

 

Check to make sure your main upper hose and lower hose are connected well. I mentioned this in another thread but, this 1st gen Tacoma is the only vehicle I have owned that I regularly check the hose clamps on. I get that same occasional drip, that left unattended, turns into a drip drip and so on. Pretty soon your low on coolant.

Just filler up and keep an eye on it.

 

Thanks for the fast responses guys, I will fill it up tonight and check the clamp. Hopefully that solves the problem!

 

in my experience the stock hose clamps work perfectly if you don't mess with them. if you have screw type clamps then someone has messed with it in the past and leaks are possible and you'll need new hoses and oem clamps. when you work on the hoses you have to put the oem clamp back in the exact same spot on the hose in the same groove it created. if it's been screwed up with a screw style hose clamp, that hose is ruined and simply going back to an oem clamp won't fix it without new hoses.

 

Worm clamps are perfectly fine and a hose isn't ruined because a squeeze clamp wasn't used. The odds of having a failed hose that someone tried to use a different clamp on is possible though.

If you can see 1 drop, you have to assume there have been a lot of drops you haven't seen. It should be dry entirely.

 

This might be a dumb question, but there is not a difference between red (whats in there is red) and green antifreeze? As long as its 50/50 of Ethylene Glycol and water, its fine?

 

There is a difference but Prestone (green coolant) will say their coolant is compatible with other coolants. You either have Toyota coolant or possbily Zerex in there. You should keep the coolant the same and not mix - This is best practice. Visit your local Toyota dealer and pick up a gallon of Toyota long life coolant concentrate. You will want to mix it 50/50 with distilled water. A food grade container with graduated volume level marks is handy for mixing. Like this one:
*4 Quart Measuring Cup https://amzn.to/2Gq4a0W

This Lisle spill free funnel is also nice for when you're doing coolant renewals:
*Lisle Spill-Free Funnel https://amzn.to/2SnrPFV

 

You're best off using whatever color coolant is already in there. Mixing can cause issues.

You might as well check your coolant in the radiator (when it's cooled down) and look for any oil sheen, as well as check your oil for any signs of coolant leaking in and watering it down. I had a slow head gasket leak on an older Toyota that would cause me to bubble up when I came to a stop, but was fine at highway speeds. Your heads are probably fine, but it's something to look at.

 

with the 3.4 motor the most common sources of coolant leaks are radiator top and the small lines that feed the IAC valve. The less common ones are the thermostat bypass tube under the lower intake and the core plug(s) under the separator plate (back of the block), especially the D/S one if the coolant has not been replaced regularly. On the 4 cyls with higher mileage +250k the head has a tendency to develop small cracks.

 

Since you don’t have the time or means to fix the problem yourself.
I, myself, would fill the reservoir with Zerex Asian Formula or Valvoline w/zerex for Asian.
Then take it to the shop.

The coolant is leaking some where. The leak needs to be addressed.
Yes, some coolant will “evaporate” over time from the reservoir, but it usually takes year(s).
Not months or days.

If you do ever find time to diagnose it yourself
I’d start with a basic cooling system pressure test.
You can even get a loaner tool from some parts stores to do this test.

Good luck to you OP.
Hopefully you get it fixed and back running soon.

 

Filled up the reservoir, after about of week the level dropped again from the full line, down to about 3/4 Full. I will keep an eye on it this week and see what happens.

I did notice that the carpet on the passengers side is wet. I am wondering if it might be the heater core..?

 

Buy some UV dye made for coolant. Then when it gets low check all over your engine bay and the wet spot on the carpet and you'll know exactly where your coolant is going. Hopefully it isn't burning it.

 

You should be able to smell if it's leaving coolant into the cab.