Coolant Leak - any thoughts??

[t4rain]

I noticed my coolant was leaking in my driveway the other day so I opened the hood to see my coolant reservoir cap wasn't fully pushed down/secured to the reservoir and the coolant was VERY low - almost all gone. I went to Toyota and got coolant to fill it up (1/2 water 1/2 coolant) and popped the cap on tight.

It is still leaking from somewhere but i can't be certain where it is.
-I just had my water pump replaced 20k miles/1.5 years ago with the timing belt
-i have the transmission cooler bypass (installed 50k miles ago)
-No check engine light ever came on and I'm pretty sure my temp gauge never got more than halfway up.
-Haven't noticed a difference in the way it drives

I see slight leaks from the top of the radiator (pics below) but nothing like what i see on this thread which is leaking out of the bottom

I'm taking it to the mechanic tomorrow (i'm not mechanically inclined) but wondering if you guys have any initial ideas

 

[mtbtim]

You don't need to be mechanically inclined to find a leak. You just have to be observant. Look under the truck in the area where the coolant is pooling or dripping. Then look to see if there's a logical place it's coming from like the lower radiator hose or thermostat connection or water pump. If it doesn't look like it's coming from any of those, look up to see if it's dripping down from something up above. It could be the overflow tube is cracked, it could be a leak in the radiator itself or it could be the upper radiator hose. If you spend enough time looking at it, I'm sure you can figure it out without paying a mechanic. Have a little faith in yourself and figure it out. It may be be a very simple fix like replacing a hose and you'll save yourself some money.

 

[4Runnin2000]

From the pictures and from the splatter it looks like it's coming from the core itself. The seam where the metal meets the plastic. That's the most common place usually. Hard to tell from a picture. When it cools down you can try to run your finger in there and try to see where most of the coolant is coming out of. Mechanic will know for sure when you take it in. Worst case scenario, you need a new radiator. Just make sure he doesn't put a junk one in there. Or it will leak again real soon.

Also what Mtbtim said

 

[Aznwolf118]

an if its the radiator itself.

JB weld won't work, it looks like it does and is very temporary but after a while it will still leak.

i ended up pulling the radiator and brazing where the leak was.

 

[nissanh]

Looks like you have the factory radiator. Before it gives you a pink milkshake, get a new radiator.

 

[StreetCreeper]

And get a Toyota radiator cap while your at it. Not that parts store stuff. The cooling system is pressurized when hot and it is only as good as its weakest link. If your cooling system loses pressure, the coolant will boil at a lower temp and cause issues.

 

[mtbtim]

If you figure out it's the radiator itself leaking, buy yourself an OEM one or other you've heard is good and install it yourself. It's pretty simple and it doesn't require any special tools.

Here's a video I made of installing an external trans cooler and it includes replacing the radiator. Take up the challenge and learn how to fix your truck. You'll be amazed how easy these repairs can be if you just take your time and have a good write-up or video to follow.

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