Not seeing coolant circulate in the radiator...

Capnemo

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I installed new water pump, thermostat, timing belt etc, the original radiator was crumbling so just installed a new rad with new hoses, everything Toyota parts.

Had flushed the coolant numerous times lastly with distilled water. Filled with new Toyota red. Had the 4r on an incline to burp the system and I did not see the fluid circulating, had heaters open and idling for 15 minutes, water temp gauge is where it always is, below halfway. When I squeezed the upper hose coolant flows out the top of the rad, no bubbles.

After 15 minutes the coolant finally got lukewarm but I never did see coolant circulation, although about once a minute I would see one small bubble pop on the surface of the radiator neck. Did an errand, drove 25 minutes total not all at once, eyes on the temp gauge.

Back on the incline, cap off, the upper hose is hot, coolant is hot, but I still do not see circulation. No pressure hiss when I carefully removed the cap with a rag.

Shouldn't I be able to see active circulation?
 
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I doubt it but supposed there is a possibility. I was watching the Tim's Youtube on the iPad as I went, I confirmed the jiggle valve was at 6 o'clock and remember thinking about which way it should go in.

Doesn't mean I didn't but....

I should see movement correct?
 
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you may or may not see movement..sometimes it's hard to tell..I say if you've gotten all the air out of the system, the hoses are hot and the temp gauge is right, call it a day.
 
you may or may not see movement..sometimes it's hard to tell..I say if you've gotten all the air out of the system, the hoses are hot and the temp gauge is right, call it a day.


It's a cool day, 62F, if not seeing fluid circulate is sometimes normal then great, but I would like to know now if there might be a problem. I guess my coolant gauge will let me know?

Can one see the jiggle valve from the backside of the thermostat? I definitely was
looking at the jiggle valve and orienting it as exactly at 6 O'clock as I could so if it is not really visible on the reverse side then the thermostat is inserted right way around. But maybe there is a a corresponding hand of the jiggle valve on the backside?
 
if your t-stat was in backwards it wouldn't be working right, sounds like your temp is consistent. if it were spiking then I'd say you have a problem.

I've worked on other vehicle cooling systems, but not the 4R, so I'm not familiar with the jiggle valve...Either way, principles are all the same.
 
Do you have a cheap bluetooth code reader or something similar like a Scanguage? The Torque app for your phone allows you to see coolant temps if it connects. Best way to know for sure.
 
I have a bluetooth code reader, will not work with my iPhone however I have an old and slow inexpensive Android tablet I was going to donate to Goodwill, I bet that will work. Thanks...
 
When your stat is closed the coolant just circulates within the heads I believe. Once the stat opens it will send water from engine to rad to be cooled. you may not see much. Drive it and see if coolant stays in normal operating range, then you know.
 
Try the heater, if it's hot you must have water circulation. When I was flushing mine about half the water that came out was cool and half was hot even though it ran for 20 minutes and the heater was hot.
 
You might be over thinking this one.

Thermostat is installed in the correct position, you have heat, temperature seems to be normal and no air bleeding out of the cooling system...

I think you've got it. They're a pretty simple coolant circuit, so don't over think if you don't need to!
 
You might be over thinking this one.

Thermostat is installed in the correct position, you have heat, temperature seems to be normal and no air bleeding out of the cooling system...

I think you've got it. They're a pretty simple coolant circuit, so don't over think if you don't need to!


Ya, I tend to do that sometimes, especially on critical stuff like cooling and brakes.
 
For years, I had read that I could watch the coolant circulate if I uncapped the radiator, started the car, and watched the inside of the radiator through the open cap.
But...every time I tried it (on 1 Toyota 4WD truck and 2 Land cruisers), all I got was the coolant pushing up and spilling out the top of the radiator.
 
For years, I had read that I could watch the coolant circulate if I uncapped the radiator, started the car, and watched the inside of the radiator through the open cap.
But...every time I tried it (on 1 Toyota 4WD truck and 2 Land cruisers), all I got was the coolant pushing up and spilling out the top of the radiator.

Throttle up to 1500-2000rpm and hold it there. It will spill out if you let the throttle drop.
 

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