2006 v8 might need a new motor (1 Viewer)

[IslandJ]

On two hour trip the other day my 2006 4runner v8 w/220k started steaming off coolant from the over flow and neck. The temp gauge never increased.
Quickly pulled off the freeway and shut it down. Called a tow truck and towed it to a shop.
The radiator was two years old, although the plastic was melted on the neck and I’m assuming internally. Oil looked fine, I changed a couple weeks ago. Timing belt and water pump were still with in the recommended interval before replacing again.
Talked to the shop today and they did top off the coolant and ran it for a while. Was a little rough sounding they said. Also, had some bubbles come up through the neck of the radiator.
I’m having a new Denso replacement radiator being shipped to the shop along with a thermostat to see if the bubbles still persist, but it does sound like a blown head gasket.

A couple questions.
What would fail that the engine would over heat with out showing a temp increase?

Any recommended sources for a used vvt-i v8?

The shop recommended just replacing the motor with a low mileage used unit rather than even pulling the head off, if the bubbles continue with the fresh radiator

 

[alia176]

I'm a DIY guy so my vote is for you to pull the heads, then do the necessary steps. Pulling the heads off on this engine is much easier than some other V8s or V6.s. My daughter and I are doing the HGs on her 3rd gen thread link, and the 2UZ-FE should be much easier compared to her engine 5VZ-FE.

Doing a leak down test and a compression test will tell you what's going on, but it doesn't sound like you damaged anything by being smart and shutting down the engine quickly. When this happened to my daughter, I tossed in a bottle of Barr's radiator stop leak and it stopped the HG leak in less than five min. She drove like this for few months until we were able to tear down the engine properly. Some folks run Barr's product for years!!!

Your mechanic makes more money by an engine swap than pulling the heads, sending them off to an engine shop, getting them back, reinstalling them back on the engine, and so on and so on. In my mind, buying an used engine could potentially have the same issue so it's a gamble. Just for reference, my engine is all original at 426,xxx mileage so you may have a fluke of an engine!!

Your temp gauge never showed the overheating condition because they've been "dumbed" down to be less sensitive. Perhaps you didn't overheat long enough for the temp to actually climb high enough to move the temp needle, but that's a WAG on my part. On the 80 series, we do a mod to make this temp gauge more sensitive and you wouldn't believe how much my needle moves now.

 

[IslandJ]

I'm a DIY guy so my vote is for you to pull the heads, then do the necessary steps. Pulling the heads off on this engine is much easier than some other V8s or V6.s. My daughter and I are doing the HGs on her 3rd gen thread link, and the 2UZ-FE should be much easier compared to her engine 5VZ-FE.

Doing a leak down test and a compression test will tell you what's going on, but it doesn't sound like you damaged anything by being smart and shutting down the engine quickly. When this happened to my daughter, I tossed in a bottle of Barr's radiator stop leak and it stopped the HG leak in less than five min. She drove like this for few months until we were able to tear down the engine properly. Some folks run Barr's product for years!!!

Your mechanic makes more money by an engine swap than pulling the heads, sending them off to an engine shop, getting them back, reinstalling them back on the engine, and so on and so on. In my mind, buying an used engine could potentially have the same issue so it's a gamble. Just for reference, my engine is all original at 426,xxx mileage so you may have a fluke of an engine!!

Your temp gauge never showed the overheating condition because they've been "dumbed" down to be less sensitive. Perhaps you didn't overheat long enough for the temp to actually climb high enough to move the temp needle, but that's a WAG on my part. On the 80 series, we do a mod to make this temp gauge more sensitive and you wouldn't believe how much my needle moves now.

Replaced the radiator, thermostat and gasket. Seems to be running fine with no bubbles. Going to keep an eye on the coolant levels and instal or update the temp gauge

 

[alia176]

Keeping my fingers crossed for ya!

 

[alia176]

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