Looks like the Thermocure worked. Will never be going back to the prestone cleaner. This stuff made the stuff coming out look like something I've never seen before. Idling at 200, 170 with the heater on. OBD and dash temps now line up as well.
Overheating Issue: Cooling System Overhaul
- Thread starter Rider620
- Start date
Well, maybe not.
I don't know why its reading two different temperatures, but this was after driving around for half an hour and then going up a steep grade holding 2700rpm, no AC on. Went from 210 on the dash to what the photo shows. So I hooked up the scanner and it says 228, but it was at 231 before the photo.
I don't know why its reading two different temperatures, but this was after driving around for half an hour and then going up a steep grade holding 2700rpm, no AC on. Went from 210 on the dash to what the photo shows. So I hooked up the scanner and it says 228, but it was at 231 before the photo.
Bummer. Does this only happen at highway speeds when more load is put on the engine? If so, that was my issue.
Based on my experience, I'd pull the radiator cap and check inside the top of the radiator for contamination. My OEM system would heat up at highway speeds if chips/debris gathered in that area. Another thing I noticed was that I couldn't trust my thermostat once my ECTs had gotten too hot (240-255* range).
Note: I wasn't boiling out coolant so I knew my cap was holding pressure.
Hope you get it figured out.
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I might go for a second round of thermocure and try more agitation and pulling the plug on the block. Heater is blowing very hot currently and if I run the heater it keeps temps down where it should be. Guessing there is just more stuff in the system.
I pull the plug from the block and flush it before adding TC. There's a bunch of stuff down in there that TC doesn't need to convert because it's all trash and needs to come out. I would definitely back flush the radiator to ensure you don't have trash plugging it up.
BTW, once you get the 8mm square socket head plug out, you can run a socket-hex plug to make the plug install much easier because it stays on your extension as you fit it between the pre-cats.
I wasnt able to get the plug out due to not having the right socket. So I ordered it last week and worked on it today. Coolant didnt come out horrible, a little cloudy. Sprayed some compressed air into there and agitated it. Got covered in coolant when it came out. Radiator had a ton of sediment in it as well today so I opted to run another dose of Thermocure and drive it til next week and see how that does. My commuting motorcycle blew the motor today so Jeep is my last resort.
Flushed the block and head again with thermocure, no more chunks or nastyness came out. Drove to work today and all seemed fine til almost 2 hours into the drive, went over 210 and stayed about 220 or so. Going to try swapping radiators and see what that does. Thats the last option at this point. The flow seemed a little slow this time when flushing with a garden hose and topping off with fresh coolant.
New radiator seemed to do the trick. It flows much better than the one I put in. Now I'm running too cool though. Around 150. Maybe an air bubble in the system. Temp gun verified 144 upper rad hose just past the thermostat, 99 right below the temp sensor. At least its not getting hot now...I will see about finding a shop to maybe repair the mopar radiator as its build quality seems much better than the Denso I put in.
The only thing which will cause your too cool scenario is a bad thermostat. It’s stuck open.
Is it the same thermostat you were running when you were overheating?
Brand new OEM Mopar thermostat. So not the same thermostat as when I was overheating, but still overheating and troubleshooting. I had it out yesterday when installing the radiator and it was closed. Not seeing flow in the top of the radiator so wouldnt that indicate the thermostat is closed?
Welp, found the issues, they sent me a 160F thermo not a 195F thermo.
I bought two auto parts 195s and watched both open at 160 in hot water.
I wouldn't install anything until you verified it works.
Saying that after having installed/reinstalled my water neck like 10-15 times in two years.
-Mac
Put in a mopar 195F stat and all works well now, except for a small leak on the top of the new radiator at the pinch seam. What a joy. Temp has not gone over 200F now since the new rad and tstat. Going to get the mopar radiator worked on by a shop and see if they cant unclog it and then I'll toss that back in and toss the denso. Its always something.
The Mopar will fail eventually too. Usually cracks on the top plastic tank. And, likely can't repaired anyway. I have a Denso in mine and it's been great. I didn't notice earlier in the thread if you mentioned it but if it's still under warranty, return to a replacement. Also, was it purchased on Amazon? If so, it might be a counterfeit. Amazon sells a lot of counterfeit parts. Not sure if anyone is counterfeiting Denso radiators but it's always possible.
Rock Auto, cant take the radiator out and wait for a repalcement, I need it for commuting to work currently. My OEM mopar lasted 140k miles and 22 years.
That's about normal life expectancy for a Mopar radiator. It's not repairable if it's leaking. Theoretically it could be repairable if you could buy replacement parts but in reality, it's not repairable. If it's just clogged....then maybe they can do something for you but most likely, they will just separate you from your money. Unfortunately.
Some people have reported having good luck with the Murray radiators from OReilly Auto Parts if you need one quickly. I'd still replace it with a Denso but I can understand why you might not want to if you've had bad luck with a Denso already. In my case, when buying aftermarket radiators for any vehicle, I usually pick Denso whenever there is a Denso radiator available.
Some people have reported having good luck with the Murray radiators from OReilly Auto Parts if you need one quickly. I'd still replace it with a Denso but I can understand why you might not want to if you've had bad luck with a Denso already. In my case, when buying aftermarket radiators for any vehicle, I usually pick Denso whenever there is a Denso radiator available.
While there may be an ever so slight difference between the two; you would probably be hard pressed to find the difference(s).
The manufacturer doesn't advertise the differences unless they have corrected a production defect.
Typically it's because they changed the manufacturer of the sourced part. Worst case it goes from made in USA to China.
-Mac
-Mac
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