Coolant level in radiator?

[Plains Cruiser]

Recently I had my headgasket done and then the very next day my radiator failed. I checked the new Aisin radiator this morning and noticed the coolant level seems somewhat low, but the overflow reservoir has plenty in it.

One other thing to add is that there was still slight pressure in the system and the truck was last driven close to 24 hours ago.

Should I add more coolant to the radiator itself? Or does everything look normal?

Tia.

 

[leonard_nemoy]

Looks good to me

 

[LandLocked93]

+1 Looks good.
The level in the radiator when cold should be just above the top row of fins inside.

 

[-Spike-]

I completely disagree with every previous comment. The radiator should be 100% full, to the bottom of the cap, period. However, sometimes it takes a few hot/cold cycles to fully purge all the air from the cooling system after work is done on it. This happens automatically due to expansion and contraction, as long as there is ample coolant in the overflow (AKA expansion) tank and there are no leaks in the system allowing air to get in. Also contrary to many posts on this board, it is not necessary to go through any special methods or procedures to purge the air from the cooling system- it will happen without any of that if the system is operating correctly.

 

[LongDuck]

Further, the overflow bottle is ABOVE the Full mark, and would lead me to believe that the Radiator Cap may not be allowing coolant to be sucked back into the Radiator. As it heats up, it forces some into the overflow (*as it should), but that's not coming back in when it cools.

To OP, when you the Radiator, did you replace the Radiator Cap?

 

[Plains Cruiser]

Thank you! It should be the cap that came with the Aisin radiator. I’ll make a trip to the dealer and get a Toyota one just to be sure.

 

[-Spike-]

Air can leak into the system anywhere from the hose inside the coolant bottle above the coolant level, to any hose or connection in the cooling or heater system. And a leak may allow air into the system without allowing coolant out, although it's usually a two-way street.

 

[LandLocked93]

The radiator should be 100% full, to the bottom of the cap, period.

This appears to be how it shows in the pic, but hard to tell really.

As it heats up, it forces some into the overflow (*as it should), but that's not coming back in when it cools.

Judging by the pic, and assuming the engine is cold, there is no room for fluid to go back into the radiator. The rad is full.

Just wanting to learn here, but by the by my experience has been that the rad level has never maintained much above the top row. Regardless of burping or manual fill. But it's also the vintage radiator, and green coolant (but a new OEM cap fwiw). So maybe that matters somehow?

I think also that elevation matters. My trail runs go from 6500ft to 11500ft on the regular. The overflow (res bottle) level will vary greatly after each run. It could start out at 'Full' @6500ft, but be at 'Low' (after 9hrs and elevation changes) upon return.
But then a quick errand around town will return the res bottle back to 'Full', or near to. As so on. Or it can start and end at 'Full', but an errand around town will kick it above 'Full' upon return. But then another trail run will bring it back to previous behavior.

Orrrr....maybe I'm describing the indicators of immanent failure (and if so please let me know) lol.
But it's always done this since purchase 5 years ago. I've added a little coolant maybe once a year over that time. But after doing so the res bottle just takes on that extra fluid after a run and the rad level remains just above the top row.

 

[Kernal]

How did the old radiator fail, did a tank (top or bottom) blow off or crack?

IME it can sometimes take a few days for all the air to work it's way out of the system, but if the radiator cap, overflow bottle cap and tubing are working correctly IME the fluid should be sucked into the radiator from the bottle as it cools.

So generally IME you would expect the opposite, a full radiator and low overflow bottle a few times/days or so after emptying and refilling the cooling system as the air in the system works it's way out.

Is the smaller bypass hose connected/flowing from the top of the new radiator to the upper coolant pipe? Was the Thermostat replaced/installed correctly (dingle ball vent at 12 O'clock)?

Check the cap and tubing to/from the overflow bottle to make sure they are flowing freely and aren't plugged.

 

[-Spike-]

This appears to be how it shows in the pic, but hard to tell really.

Not from what I see. The level should be up to the overflow exit port. I see the inside of the top tank, which shouldn't be visible at all except through the coolant.

 

[Plains Cruiser]

I’ll check the hose from the radiator to the overflow. Is it as simple as waiting for the engine to cool and releasing the clamp and peering inside the hose or running water through it to make sure it’s not clogged? Noob here.

 

[Kernal]

Pull the entire hose/cap assembly off the overflow bottle and radiator (release the small clamp), blow in/out the hoses and pipe to make sure nothing's blocked, reinstall.

 

[Funner]

Run your heater the next time you get truck to full operating temperature. You’ll want to make sure there is no air in those systems too.

 

[Plains Cruiser]

I think I found the culprit.

 

[LandLocked93]

Yup. If not the problem, def a problem regardless.

 

[LongDuck]

Were you able to blow it out of there and reattach? What's plugging up the port?

 

[Plains Cruiser]

Were you able to blow it out of there and reattach? What's plugging up the port?

I tried cleaning it out with a paperclip but wasn't too successful. It was really gunked up. I'm not sure exactly what the substance is? I'll plan to purchase a new assembly and see how that changes things.

 

[Kernal]

If it's that hard I'd worry that it might be left over headgasket/block sealer dumped into the cooling system by the previous owner??

What do you see looking down into the radiator (cap removed), got a photo?

 

[Plains Cruiser]

If it's that hard I'd worry that it might be left over headgasket/block sealer dumped into the cooling system by the previous owner??

What do you see looking down into the radiator (cap removed), got a photo?

I’ll have to grab a photo in the daylight tomorrow. I did just get the headgasket replaced less than a month ago and have a new radiator, so more likely than not I should be ok right? (Barring no botched work.)

 

[leonard_nemoy]

Pull the entire hose/cap assembly off the overflow bottle and radiator (release the small clamp), blow in/out the hoses and pipe to make sure nothing's blocked, reinstall.

What about all those carcinogamen critters living in the hose. Won't he get cancer?

Well he is in Nebraska not Cali so he should be fine I guess.