To rule out any leaks (and air pockets) I'd try a couple of things -- first do a positive pressure test, and if it passes, then use a vacuum filler and see if it holds vacuum before you fill it. That will rule out any leaks (both positive and negative pressure) as well as make sure you don't have any pesky air pockets. If it still builds up air in the system after all that I'd say time for new head gaskets. But with the lack of combustion gas in your tests hopefully it's just a huge air pocket or leak.

 

Hey that is really cool. Thanks man, I never knew that tool was out there. I will order one!

cool intro to the tool

 

Very well. You're on your own my friend.

 

You're welcome, sometimes vacuum filling is the only way to get most the air out. I'm about to do it on my truck which has a very similar issue (minus the overheating).

 

99% of the time cooling issues with the 1uz are NOT head gaskets. The motors are just relatively tolerant of cooling issues. If the HC testing is showing nothing, perhaps you should take the vehicle to an experienced mechanic and let them check the cooling loop out.


Because this is a swapped car, it's very easy for the factory bleed point to not be high enough to get air out of the system.

 

Sorry Banshee, I did not mean to make you angry. I need all the help I can get, so don't take my comments as meaning I don't want your help. All I do ask is that you read the thread, both your comments were really not helping find the issue. (you were not the only one, go read the post and see what I mean) They were both answered and or described in earlier posts. I suppose it just goes with the territory on mechanical boards, there are people who just want to show how smart they are, and those who comment after only reading the one or two posts in the thread.

Please, I'd love to hear input.

 

I have nothing to add but nice way to diffuse the situation. Come on banshee join back in the Convo.

 

What kind of cooling fan setup do you have? OEM? Can't tell from the pics. Try removing thermostat or drilling a few holes in it? If enough air is trapped in the block the Tstat might not even open. Given your lack of 'flow' along with bubbles this is a possibility.

 

I didn't want to destroy the new oem thermo, so I had a piece from another one. didn't have the bypass plug, but shouldn't make that big of a difference. Put it in, bled a little and test drove. no difference at all. Though I must say I love hot rodding that RV, people are not used to seeing a Toyota rv hauling *** sounding like a race car, it is rather awesome.


Here are some picts. the fan is a spiral high flow, radiator is an after market one many people use for a v8 conversion. I have a air dam built that scoops air and drives in into the radiator, see it on the bottom. the fan on the side is a combo oil and trans cooler that is vented out of the bay.

 

 

one thing that I have noticed. when you squeeze the top hose and rev the motor, I am not feeling it expand. it has in the past, but not right now. it is almost like the fan blades are half the size or something. guess that could be the cavitation from the bubbles. one other clue i guess..

I did find this cool video to test for coolant in the oil. I did it, no boil...so yet another test that shows no blow head gasket.

 

No wonder, its not an LS400, they don't use a funky radiator like that, its probably trapping lots of air.

 

many people have used these radiators for a 1uzfe swap.

 

This is rare, but everything seems to point to a lack of coolant flow. If you have confirmed that there are no restrictions in either the radiator or the engine, then there's only one thing left: the water pump itself. Even though the bearings and seal may appear fine, it is possible that the impeller is defective or severely corroded, and is no longer performing as a centrifugal pump.
Using the garden hose setup, and the upper radiator hose removed, let water flow into the radiator until it comes out at the top of the engine. Start the car, quickly observe if the flow coming out of the engine increases, AND if it responds to throttle taps. If not, you've got a bad water pump.

 

I will drain the coolant out tonight or tomorrow, then ill try the garden hose thing. See what I find out. I will use that cool vacuum fill tool to pull a vacuum and see if there are any leaks, and then fill. hopefully this will fix the odd *** problem.

If you watch the video showing the pressure gauge, when I rev the pressure does go up. do you think that counts as "responds to throttle taps"?