Is your radiator overflow tank level dynamic? (4 Viewers)
- Thread starter Bambusiero
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COYS
SILVER Star
Looks like there are two part numbers for two rad caps that fit the 80?
16401-54750 (cheaper)
16401-15210
COYS
SILVER Star
Tank is still above high mark. Radiator shows full.
Did you ever solve this problem?
My 80 is doing the exact same thing. Same fluid amount, brand new OEM cap from wits end.
Did the new reservoir and tubes fix your issue?
COYS
SILVER Star
I ended up sucking out the extra coolant over two or so days of driving, each day sitting overnight. The coolant level hasn't moved since which is now over half a year ago. Kinda weird, huh?
P.S. I swapped out the reservoir for new purely for vanity reasons
Last edited:
Gotcha, thank you for the reply. Did the coolant suck back in before you replaced the resi and hoses?
COYS
SILVER Star
No. The issue was there was additional coolant showing up in the res.
Correct... And you said over a few days of driving it sucked it out... is this before you replaced the resi...? or after..?
COYS
SILVER Star
b4. the resi has nothing to do with it in my case.
Just reading through this and appreciate the tips about checking the overflow tank to overflow cap hose. I also need to check connections, over time my overflow level has gone way down and I occasionally see a little seepage out of the connection from radiator to overflow tank on the radiator side. Replaced the old hose clamp with a new one but still happens occasionally.
This thread was helpful so I thought I'd record my experience.
Background - My truck had recent maintenance (lots of old hoses replaced among other things) to include a new radiator.
Symptoms - After driving, puddles of Toyota Red on the ground under the coolant overflow tank; empty overflow tank; red residue around the overflow tank cap; low coolant level (more than half gal low) in the radiator.
Actions taken - 1) Momentary but not so momentary "head gasket is blown" freak out session; 2) Trip to AutoZone for combustion gas and coolant system pressure test kits and more Toyota Red coolant; 3) Tested coolant system pressure - held pressure; 4) Combustion gas test (with blue ink) - no gases detected; 5) Tested radiator cap - passed; 6) Didn't believe any of the tests so re-ran them all with same results; 7) Didn't want to admit being stumped to my wife and felt like spending more $ so bought new OEM radiator cap (old one was also OEM);
8) Took a step back and finally examined the coolant overflow tank and noticed the overflow tank cap has two possible (and distinct) orientations; I didn't take a photo so I'm using one I found on the internet to illustrate. Key point - the tab (in red) needs to be on the back side of the tank. If your cap is installed correctly, then you can trace an uninterrupted tunnel from the radiator to the bottom of the overflow tank. This will allow for proper coolant level adjusting as Mr. T intended. If it's backwards, the hose from the radiator will connect to the cap and dump coolant through a small hole into the tank and the hose that's inside the tank will connect to the discharge hose. For those scoring at home, this will, under the right conditions, give your precious coolant a direct path from the tank to the ground beneath your truck. Most importantly, there will not be a way for the system to suck coolant back into the radiator when it needs it.
9) Discovered the cap was incorrectly installed and reversed it. Topped off coolant. Burped system. Topped off overflow tank. Coolant level has been steady for the last month.
I had no idea the cap orientation mattered. The mechanic even mentioned the coolant dripping but thought it might have been the level settling after the new radiator install. Anyway, It was a simple thing to overlook. Lesson learned.
Background - My truck had recent maintenance (lots of old hoses replaced among other things) to include a new radiator.
Symptoms - After driving, puddles of Toyota Red on the ground under the coolant overflow tank; empty overflow tank; red residue around the overflow tank cap; low coolant level (more than half gal low) in the radiator.
Actions taken - 1) Momentary but not so momentary "head gasket is blown" freak out session; 2) Trip to AutoZone for combustion gas and coolant system pressure test kits and more Toyota Red coolant; 3) Tested coolant system pressure - held pressure; 4) Combustion gas test (with blue ink) - no gases detected; 5) Tested radiator cap - passed; 6) Didn't believe any of the tests so re-ran them all with same results; 7) Didn't want to admit being stumped to my wife and felt like spending more $ so bought new OEM radiator cap (old one was also OEM);
8) Took a step back and finally examined the coolant overflow tank and noticed the overflow tank cap has two possible (and distinct) orientations; I didn't take a photo so I'm using one I found on the internet to illustrate. Key point - the tab (in red) needs to be on the back side of the tank. If your cap is installed correctly, then you can trace an uninterrupted tunnel from the radiator to the bottom of the overflow tank. This will allow for proper coolant level adjusting as Mr. T intended. If it's backwards, the hose from the radiator will connect to the cap and dump coolant through a small hole into the tank and the hose that's inside the tank will connect to the discharge hose. For those scoring at home, this will, under the right conditions, give your precious coolant a direct path from the tank to the ground beneath your truck. Most importantly, there will not be a way for the system to suck coolant back into the radiator when it needs it.
9) Discovered the cap was incorrectly installed and reversed it. Topped off coolant. Burped system. Topped off overflow tank. Coolant level has been steady for the last month.
I had no idea the cap orientation mattered. The mechanic even mentioned the coolant dripping but thought it might have been the level settling after the new radiator install. Anyway, It was a simple thing to overlook. Lesson learned.
I had a new radiator, thermostat and water pump installed 2 weeks ago. A couple of days ago I noticed a good drip coming off of the passenger side fender flares near the firewall. After searching on here I believed that it was a rear heater hose. For the life of me I could not find the origin of the leak. I removed the radiator cap to see how much coolant was in there and the coolant gushes out of the cap with a fair amount of pressure. Truck was sitting for more than a day when I did this. I put the cap back on and no more leak.
Any ideas on what could cause this?
Any ideas on what could cause this?
- Thread starter
- #54
I've had the lower main radiator hose do that after a complete service - just dribbled a bit after a short drive - just needed a bit more tightening.
Sounds like your AC drain.. its on the passenger firewall area..
It's leaking again. It's coolant. I haven't run the AC lately. Would there be coolant coming out of that drain? The black pad behind the AC lines are wet on the bottom. The heater hoses to the right of this picture must be leaking but I just can't find the leak.
Thank you for your reply.
It's not the AC drain. That has nothing to do with the engine coolant.
Was the drip coolant? Green or red depending on coolant type? Not clear like water?
When you opened the radiator cap after it was sitting for a day, then there should be NO pressure on the radiator UNLESS you have a bad radiator cap.
Get an OEM Toyota radiator cap. They don't fail and they fit like they are supposed to on an OEM radiator.
The shop that did your WP, Hose, radiator, did they "burp" the system?
What brand of radiator do you have now? OEM or cheap aftermarket aluminum from O'Reilly or someplace that the shop installed?
Now that the front half of the cooling system is sealed, tight, and it can build pressure, the hoses and heater lines on the back side now have to deal with increased pressure and if those hoses were not replaced, it is very likely they will leak now.
OEM radiator. Toyota red coolant.
I'll double check the cap.
The rear hoses were not replaced.
Thanks for the reply. It makes sense, I just can't seem to locate the leak. I thought it would be up high on the firewall since it soaking the bottom part of the pad.
Heater control valve was replaced too.
Is it possible it's "residual" coolant soaked into the pad from the shop dumping coolant down the outside of the firewall during the heater valve changeout? I doubt that's the case, because that can be done with only a quart of lost coolant.
I'm thinking one of the hoses on the passenger side is leaking after it heats up and it pressurizes.
The OEM radiators come with a new cap. It should be the yellow label top.
How about a couple wider angle pics for us to see more areas? Around the radiator, the heater valve, the coolant hoses?
