Head gasket failure on the V8?

[bergs]

Are you saying that you recently, as in the last couple of days, changed the gasket? Or was this done 30k ago during the TB change?

Either way, I would check/replace the entire T-Stat with an OEM, and drain all the green coolant out. Following that I would replace with OEM Pink coolant from your local dealership.

Just prior to doing this, warm up the engine and do a hydro carbon test on the coolant system. Your auto parts store should have the tester and the fluid. At least you can say you knocked that check out in regards to your concern about the HG. Blue fluid = no hydro carbons / Yellow fluid = hydro carbons present.

A failing T-Stat, leaking T-Stat could do it. The OEM coolant from my experiance seems to work a lot better in these toyota engines, so since you're going to be in there might as well change it.

Replaced the gasket about 2 weeks ago.

Since I have never experienced a t-stat failure personally, other than the occurrance of being stuck wide open (which obviously would not replicate my issue), what would a failure look like as far as my situation is concerned? I'm guessing slow movement but again, nothing to reference it against.

Exchanging green coolant with pink....noted. Thank you.

 

[bergs]

It's hard to say. I came from the landrover world and I saw several clogged radiators. Many of them had sludgy crap in them, it was linked to non compatible fluids. If it were my truck I would flush it completely and refill after with oem fluid.

That's now two posts suggesting replacing the coolant.

Would I want to backflush the radiator prior to doing this?

 

[ebg18t]

That's now two posts suggesting replacing the coolant.

Would I want to backflush the radiator prior to doing this?

To be safe and sure all the old coolant is out I would do a good water flush.

 

[bergs]

Been swamped at work the last couple months and haven't logged in to update this thread but ended up finding the problem....

Failed thermostat (did not fully open)

 

[gshadow325]

Been swamped at work the last couple months and haven't logged in to update this thread but ended up finding the problem....

Failed thermostat (did not fully open)

OHH THANK GOOD NESS, i dont want to hear about failed head gaskets on the V8's !!!!!

 

[JB.]

Thanks for following up.

 

[bergs]

Has the proper coolant always been used? I ask as I have seem sludgy systems when people mix/match the wrong antifreezes.

So, I addressed this question way back when but I figured I'd re-answer it since I did indeed mix coolants but was oblivious to the potential effects.

Mixing coolants is a really dumb idea,people, and I have now seen the error in my foolish ways as the failed thermostat was only part of the original problem. My truck is still over-temping when towing and I am convinced the bigger issue has always been the mixed coolants. My radiator has a blockage which means I will be paying someone to correctly flush my cooling system.


:clap2:

EDIT: BTW, Sanel Auto sells mfg-specified coolants (not premixed). I paid ~$17/ gal

 

[05mike4R]

Really?! Thats Awesome. I have a 2005 4runner 4.7L V8 is that the same engine youre talking about?? What makes it so good??