I had an obvious cracked upper tank on my radiator. Replaced with a 2 core Koyorad. For several trips none over 25 miles long, I started to see temp gauge rise and when cooled checking fluid level had to add a gallon. Could not see any visible leaks but during the incident last night, I noticed all the hoses were rock hard. Was their a burping process I missed causing an air pocket after new radiator install? Any help is appreciated as it is my daily driver.
97 LX450 radiator replacement now overheating (1 Viewer)
- Thread starter VACRUSSA
- Start date
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Bambusiero
SILVER Star
1) Did you run it for a while with a radiator fill funnel attached, allowing bubbles to purge - waiting for lower hose hot - indicating thermostat has opened?
2) Check if you are getting hot air from the cabin heater. I did a radiator flush once and - the process of thoroughly mixing coolant - wait for full warm-up - it never gave cabin heat. Finally, I gave up on waiting, pulled the PHH hose to the heater valve, burped it - back together, and then it warmed up as usual. Shrug? Not saying this is your problem...but maybe an air lock stopping circulation?
2) Check if you are getting hot air from the cabin heater. I did a radiator flush once and - the process of thoroughly mixing coolant - wait for full warm-up - it never gave cabin heat. Finally, I gave up on waiting, pulled the PHH hose to the heater valve, burped it - back together, and then it warmed up as usual. Shrug? Not saying this is your problem...but maybe an air lock stopping circulation?
FWIW, I never burp my system, fill and go, heat control valve open, recheck every day (cold engine) for a week or so, top off as needed.
Was the system overheating before the radiator was replaced? Did the old radiator just recently develop a crack?
If still overheating with a full system, you could start with replacing the thermostat and radiator cap if both are old and/or not OEM. Use only Toyota parts.
Was the system overheating before the radiator was replaced? Did the old radiator just recently develop a crack?
If still overheating with a full system, you could start with replacing the thermostat and radiator cap if both are old and/or not OEM. Use only Toyota parts.
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- Thread starter
- #4
First, as new to MUD I want to thank everyone, have been on before but finally a happy member. The culprit showed itself fully. Yesterday when bringing to shop to start diagnosis I stopped for a coffee. Before I got out steam is a blowing and I get to see a river running under truck. The "new" koyorad failed at bottom tank. Replacing with Denso and lots of toyota, tstat, o rings and that pesky heater hose. After Christmas its coming in for a full cooling system replacement.
Thanks again and hopefully I can share some of the pics of work I am doing bringing it back into shape.
Thanks again and hopefully I can share some of the pics of work I am doing bringing it back into shape.
richardlillard1
SILVER Star
If the the coolant system had high enough pressure to keep the hoses rock hard, but still lose a gallon at a time I would be doing some other tests before putting in any new components. The system pressure is 13psi and if there’s a leak it shouldn’t be making pressure as there’s a point of egress. On the other hand, if gasses are forced to enter the cooling system, it will increase the pressure and said components, which are not rated for those increased pressures, will begin to fail.
Do a block test and confirm no exhaust gasses are entering the cooling system. Smell the coolant reservoir. If it smells like exhaust, I have some bad news.
I never thought I would see the day where a coolant-related thread would make it 24 hours without someone bringing up the head gasket, but here we are. 2020 is wild.
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