Strange radiator leak (1 Viewer)

[V8addict]

Hi fellas, long time lurker, but had to get on and post as I’ve got an interesting situation.

got an 08 gx470 recently. Went to check the heater T as I know they’re an issue with the 100 series. To my pleasant surprise, it’s made of aluminum. But in the process of checking it out, I bungled it. So I went and got a replacement from the dealer and put it in. Noticed there was no coolant in the expansion tank, so I bought a bottle of Toyota red and added it in.
I also replaced the spark plugs.
When I went to start it up, coolant was gurgling out of the side seam of the radiator in multiple spots. Dripping on the ground. Certainly wasn’t doing that when I drove it home after I bought it about 50 miles.

coincidence or what?

 

[V8addict]

Hi fellas, long time lurker, but had to get on and post as I’ve got an interesting situation.

got an 08 gx470 recently. Went to check the heater T as I know they’re an issue with the 100 series. To my pleasant surprise, it’s made of aluminum. But in the process of checking it out, I bungled it. So I went and got a replacement from the dealer and put it in. Noticed there was no coolant in the expansion tank, so I bought a bottle of Toyota red and added it in.
I also replaced the spark plugs.
When I went to start it up, coolant was gurgling out of the side seam of the radiator in multiple spots. Dripping on the ground. Certainly wasn’t doing that when I drove it home after I bought it about 50 miles.

coincidence or what?

 

[V8addict]

Just noticed that when I started the car today, the radiator wasn’t leaking at all. Let it run for about 15 mins. Nothing. Could this be an indication of water pump issues? Like maybe the pump didn’t run the second time? But the first time it was running and therefore pushing coolant through all the seams?

Other weird thing was the coolant expansion tank - it has a cap with a two sided barbed fitting. The way I had it hooked up at first, it was squirting coolant out of the cap. Then I put the little rubber hose on the other side and it seemed to have stopped.
What in tarnation?

 

[AdventureFamily]

I had a very similar issue. For me no leaks on the ground anywhere, but doing a routine check I noticed the overflow tank was very low, added coolant seemed fine about a week later my wife came home and went out to get some groceries out of the car and there was coolant on the ground. added coolant so we could drive and it would seem fine and then leak like crazy etc. anyways looked the radiator over real good and found corrosion holes where the plastic meets the fins. Picked up a Denzo radiator, toyoto hose, flush and new coolant, took about 3 hours. Been perfect for going on 4 months. I thought I had an internal engine leak or something but it appears these radiators are not the best design for longevity and are prone to leak. i dont know if the leak had something to do with the temp and when the therm would open or not open? who knows. On a side note, i looked back through the Maintenance history of my 15 year old rig with 200K and this was the 4th radiator. the previously 3 were done at lexus 2 under warrantee and one out of warrantee.

 

[SteveH]

It seems like many of these trucks need a radiator before 200K miles. Because the radiator cap is under that idiot plastic shield, no one ever checks it. My brother's cap was shot, the coolant was low, and the radiator was leaking near the top. He bought a Denso replacement radiator, and the aluminum strap across the top of the radiator was much thinner/lighter, and promptly cracked. This replacement Denso is not leaking, however - but is lighter duty than the OEM radiator, at least in respect to the top strap.

My '06 had a bad radiator cap that literally fell apart when I took it off, and pieces fell inside the radiator. I took a hole saw and buzzed a big access hole in that stupid plastic cover (as did my brother) so now you can SEE and CHECK the radiator cap.

So, whatever else you do, replace the radiator cap and check it yearly for rotted gaskets or to see if it's falling apart.

 

[wrcfan]

Just noticed that when I started the car today, the radiator wasn’t leaking at all. Let it run for about 15 mins. Nothing. Could this be an indication of water pump issues? Like maybe the pump didn’t run the second time? But the first time it was running and therefore pushing coolant through all the seams?

Just to clarify things, the water pump is always running, its the thermostat that opens and closes to send coolant through the radiator circuit. So, it could be possible that things were still too cold to run through the radiator circuit?

 

[Toyoland66]

GX470's don't have heater T's, there is no rear heater.

My radiator failed at about 95k, where the tank attaches to the core. I replaced with a Koyorad and plan to replace it again when I do the timing belt at 180k as PM.

Just noticed that when I started the car today, the radiator wasn’t leaking at all. Let it run for about 15 mins. Nothing. Could this be an indication of water pump issues? Like maybe the pump didn’t run the second time? But the first time it was running and therefore pushing coolant through all the seams?

Other weird thing was the coolant expansion tank - it has a cap with a two sided barbed fitting. The way I had it hooked up at first, it was squirting coolant out of the cap. Then I put the little rubber hose on the other side and it seemed to have stopped.
What in tarnation?

You probably also have a bad radiator cap, it shouldn't let any coolant out to the expansion tank until it gets to ~14 psi or whatever they are set for, it will however let coolant from the tank into the radiator under vacuum. If your cap is bad you won't be building pressure that would force coolant out of your leak.

Re-read your original post, it is hard to decipher.

 

[V8addict]

GX470's don't have heater T's, there is no rear heater.

My radiator failed at about 95k, where the tank attaches to the core. I replaced with a Koyorad and plan to replace it again when I do the timing belt at 180k as PM.



You probably also have a bad radiator cap, it shouldn't let any coolant out to the expansion tank until it gets to ~14 psi or whatever they are set for, it will however let coolant from the tank into the radiator under vacuum. If your cap is bad you won't be building pressure that would force coolant out of your leak.

Re-read your original post, it is hard to decipher.

I replaced with a denso rad and it’s been good ever since. When I opened the heater hoses, I think I let air in and that caused increased pressure and made the radiator seam to leak. Anyway, in my experience a new radiator has always fixed a leaking radiator, not a new radiator cap.

 

[Toyoland66]

I replaced with a denso rad and it’s been good ever since. When I opened the heater hoses, I think I let air in and that caused increased pressure and made the radiator seam to leak. Anyway, in my experience a new radiator has always fixed a leaking radiator, not a new radiator cap.

Agreed that the best fix for a leaking radiator is a new radiator. I could not determine that you replaced it from your OP, it was hard for me to understand...