This is not over heating.
Where are you getting the temps from?
The OBD port via a scan tool, or just of the gauge?
Overheating problem
- Thread starter Dvaniwaarden11
- Start date
This is not over heating.
Where are you getting the temps from?
The OBD port via a scan tool, or just of the gauge?
Forgive me for not re-reading the last six pages...but maybe unplug all the O2 sensors and force it into open or closed loop...I get those two confused. Where the Jeep PCM runs on default tables rather than adjusting based on sensors.
You'll get an O2 check engine light...for sure...but curious if it reaches temperatures you're more comfortable with.
-Mac
You'll get an O2 check engine light...for sure...but curious if it reaches temperatures you're more comfortable with.
-Mac
Engine looks really clean inside,my mopar pump has a plastic different looking impeller?everything else looks great?
Lots of smarter people than me contributing and not sure if this means anything at highway speeds, but your fan does look way further back than mine. Actually I can't tell if your fan is farther back, or your shroud is further forward?
Is the shroud on correctly? That is important at highway speeds at least
The 215* reading you got today at 55 mph doesn't seem to address if it would overheat when driving at faster highway speeds up an incline. It seems like you were driving in the similar safe zone today that got you home from your recent trip (see your quotes above). But, things getting hotter at lower speeds is where I'd start looking at the fan clutch. But the fan clutch shouldn't be causing high-speed overheating like you mention above.
Did you attempt driving without the thermostat installed? Maybe something is blocked up in the coolant passages (I'm spit balling)...or maybe there's a compression issue.
Did your installer do the compression or leak down test?
Is your compression stock...no detonation happening and no performance mods in the engine build that would cause you to need to run 91 octane?
Edit: I'd want to confirm it's still acting the same at faster speeds before I did anything else. So, I would drive it faster on the highway to see if it stays around 215 or tries to head more towards 227-230+. If the ECTs get too high then simply drop back to the 55mph safe zone and get it back home.
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Wouldn't 3rd gear at 4k in the side streets help it cool down since the WP would be spinning faster at a lower load?...unless your fan wasn't pulling sufficient air through the radiator or the thermostat isn't working properly? (also assuming that the previous radiator and current Denzo are both fine like we'd hope at this point).
Also, I can't remember, did you boil test the thermostat to confirm that the new thermostat opens properly?
Sorry, OP. We'd really like to see you be all good.
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I’ve had an OBD connected when I overheated and it confirms the gauge is reading accurate. My temps in this thread have been guesstimated based off of reading the gauge. The higher temps I got today would have jumped into the red if I have driven my Jeep an hour driving it like a normal car. In general since I’ve been having this overheating issue with this motor I drive like an old lady to take it easy on how much load I put on the Jeep. For example on a long uphill I will drive 40-45 in the slow lane with flashers on and have semi’s pass me because if I put my foot down to drive faster, I WILL overheat. I understand the temps I got today don’t completely constitute as a temperature that will damage my engine, they give me confirmation that if I drove 3 hours to the forest to off-road I would 100% overheat a couple times on the drive.
A few other people in this thread have commented on that. I’m not sure what the correct measurement is. In my opinion after looking at it, it appears that that more of the fan is exposed than normal but I’m not sure what would cause that? All the parts look extremely similar to what I’ve seen on videos on YouTube. I would agree that the fan placement 100% affects how much air is pulled through the radiator but I figured at highway speeds I would have a ton of air pushing through that area regardless? I’m not sure.
Great questions about the motor. It’s what I’m leaning to now after replacing almost the entire cooling system in the last week. I actually filled up 91 today to see if there was any difference but there wasnt.
Good questions for my mechanic. I’m going to give him a call.
Did not boil the new stat. Probably should have but assumed by this point I wouldn’t be getting another broken part haha. I’ve got to imagine it’s either the fan not pulling air properly because of its placement or a motor issue at this point. The fan clutch was also new with the motor and passed the resistance test.
Yes I agree I'm not sure if the fan matters, I just thought it might be another data point to point out it is infact different. I almost thought the shroud might be different between the two not the fan, which might mean something where you're having issues, but idk. You did already check the shroud it sounds like anyways.
Also, I did not take pictures I checked, but the pic of the impeller you posted earlier looks like how I remember my new water pump looking when I replaced it in 2021, for what it's worth.
Also, I keep texting my buddies about this and they keep sending me links to LS engines on summitracing.com so I would love to fix this before they really start pressuring me hahah
That's an expensive way to resolve the issue.
If you were closer, I'd swap our fans to see what happens with your rig in the side streets. Do you hear your fan roaring pretty good as you accelerate?
That's an expensive way to resolve the issue.
If you were closer, I'd swap our fans to see what happens with your rig in the side streets. Do you hear your fan roaring pretty good as you accelerate?
Yeah I hear it spinning pretty good when driving
I'd bet an LS swap would be more difficult and more expensive than this
But just think of how amazing it would sound……lol
I heard a 5.7L Hemi a couple months back and it surprisingly didn't move the needle for me like I thought it would. And, I drove out of my way to check out that rig all because I had never seen a Hemi in a TJ.
A 5.7L Hemi is a lot of effort for only a bit more power than a turbo'd 4.0L gives you without as much effort.
Obviously, things get very impressive once you are in the 6.0L-6.4L builds, which bring on fitment issues and dealing with heat management (just what you need). Those builds are awesome, but it's not a lighthearted route to pursue since it takes time and effort or a load of cash.
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I love sound of the small block chevys, which is what I would do if I did the v8 swap. A Chevy 305 is perfect for the Jeep TJ. Should have come stock IMO
I believe you will need to work around the emissions requirements due to where you live unless your rig is old enough that the rules allow you to get around that stuff or you can register in a county that doesn't require testing. (doable, but something that needs to be dealt with).
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Trying to learn something here. The more times an engine fires the hotter it gets. The entire radiator, hoses, and block are to transfer the heat to the atmosphere, correct? Wouldn't running at high rpm's cause an overheat situation if the system cannot dissipate the heat?