Mopar thermostat alignment for weep hole

They are using scan tools to get the temp. About as useful as installing temp senders in the combustion chambers.

in what way? It's reading the sensor in the thermostat housing, so I don't know how you get any more accurate understanding of when the thermostat is opening.

Ultimately what we care about is whether the non-uniformity of thermal expansion of block and head are going lead to a warp or crack, but the coolant temperature is the best analog we have for that short of Chrysler spending insane money on a bunch of instrumentation on a model they mostly seemed only interested in cutting cost out of.
 
in what way? It's reading the sensor in the thermostat housing, so I don't know how you get any more accurate understanding of when the thermostat is opening.

Ultimately what we care about is whether the non-uniformity of thermal expansion of block and head are going lead to a warp or crack, but the coolant temperature is the best analog we have for that short of Chrysler spending insane money on a bunch of instrumentation on a model they mostly seemed only interested in cutting cost out of.

I don't know if everyone is aware, but back when the TJ's were made some of them did not contain enough nickel (if I recall correctly) which is why a lot of them cracked. Unfortunately, I don't remember all the details, but there are even stamps on them where they know which ones were suspect.
 
Sounds like you are talking about the 0331 non-tuppy head. That was a casting issue and had nothing to do with nickel content. I've heard that theory floated out there before though.
 
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Sounds like you are talking about the 0331 non-tuppy head. That was a casting issue and had nothing to do with nickel content. I've heard that theory floated out there before though.

Do they have to be mutually exclusive? Or is the specific casting issue known, like a core shift that made something too thin?
 
in what way? It's reading the sensor in the thermostat housing, so I don't know how you get any more accurate understanding of when the thermostat is opening.

Ultimately what we care about is whether the non-uniformity of thermal expansion of block and head are going lead to a warp or crack, but the coolant temperature is the best analog we have for that short of Chrysler spending insane money on a bunch of instrumentation on a model they mostly seemed only interested in cutting cost out of.

Guess how many rigs I own, have owned, have worked on, have fixed, and have solved every cooling system problem on that has ever been thrown in my lap without a single instance of ever knowing what the EXACT reading of that temp sender is? I don't need that information, no one else does either.
 
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ever knowing the EXACT reading of that temp sender is? I don't need that information, no one else does either.
Information is always a good thing. Being able to effortlessly connect to the sensor and watch on my phone while I was warming up and driving how quickly the temperature rose or how it reacted while driving, stopping etc is certainly not a bad thing! You cannot see the temperature fluctuations by watching the analog gauge on the cluster.

 
Guess how many rigs I own, have owned, have worked on, have fixed, and have solved every cooling system problem on that has ever been thrown in my lap without a single instance of ever knowing what the EXACT reading of that temp sender is? I don't need that information, no one else does either.

Genuinely interested in this - given only the gauge, what is your criteria for determining something is "wrong" in the cooling system, in terms of the extents in either direction from the middle that the needle needs to reach in prescribed conditions to indicate malfunction? To your point, most people would see 230 on a scanner and dozens of forum posts claiming a healthy cooling system should stay close to 210 in the worst of conditions, and be concerned in spite of the completely nonlinear gauge putting that on the 0 in 210, barely past the middle. Likewise, the 192 reported by the OP is barely left of the middle and even without a scanner I would have no reason to suspect a latched failsafe or incorrect thermostat.
 
Genuinely interested in this - given only the gauge, what is your criteria for determining something is "wrong" in the cooling system, in terms of the extents in either direction from the middle that the needle needs to reach in prescribed conditions to indicate malfunction?
I'm not Blaine but the answer is simple and obvious to me... significantly more real life experience with all aspects of the TJ's cooling system than anyone else in this forum. Experience trumps Joe-average with an aftermarket OBD port reader. In other words Blaine knows full well what he's talking about.
 
Genuinely interested in this - given only the gauge, what is your criteria for determining something is "wrong" in the cooling system, in terms of the extents in either direction from the middle that the needle needs to reach in prescribed conditions to indicate malfunction? To your point, most people would see 230 on a scanner and dozens of forum posts claiming a healthy cooling system should stay close to 210 in the worst of conditions, and be concerned in spite of the completely nonlinear gauge putting that on the 0 in 210, barely past the middle. Likewise, the 192 reported by the OP is barely left of the middle and even without a scanner I would have no reason to suspect a latched failsafe or incorrect thermostat.

I can't really speak to dianosing a tj cooling system in depth. But it seems a known good infrared thermometer would be a better bet than asking a pcm that is reliant on senders,wiring and the connections between them for an accurate temp reading?
 
I can't really speak to dianosing a tj cooling system in depth. But it seems a known good infrared thermometer would be a better bet than asking a pcm that is reliant on senders,wiring and the connections between them for an accurate temp reading?

I have an IR thermometer. I found that using my OBDII and app was very effective. Not sure why people don't trust sensors; they work very effectively, especially for a simple task like temperature. When you enter any major arena/stadium you can scan your body and determine your temperature.
 
My rhetorical question is this... do those OBD scanners and apps use a different temperature sender than the instrument cluster's temperature gauge does?
 
I can't really speak to dianosing a tj cooling system in depth. But it seems a known good infrared thermometer would be a better bet than asking a pcm that is reliant on senders,wiring and the connections between them for an accurate temp reading?

of course the sensor reading should be verified before being trusted (no different than checking an oil pressure sender before you tear into the engine to replace bearings), but once it's known good, it would be trustworthy enough in the short term to solve a problem. And if it's bad, that in itself should be addressed because the PCM is using that reading for important calculations.
 
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I can't really speak to dianos understanding of their ing a tj cooling system in depth. But it seems a known good infrared thermometer would be a better bet than asking a pcm that is reliant on senders,wiring and the connections between them for an accurate temp reading?

You'd have to define "good".
Research "Spot Ratio" with reference to IR thermometers to get a better understanding of their accuracy.
 
My rhetorical question is this... do those OBD scanners and apps use a different temperature sender than the instrument cluster's temperature gauge does?

of course not, but as I stated in my previous post, the gauge is so compressed that 190-230 takes place in about 10% of the span of the gauge, so the scanner provides much better resolution. It seems like you and blaine are making the case that the extra resolution isn't needed, and I'm trying to get confirmation of that, and then an answer to, if the difference between 190 and 230 isn't significant enough to need to be discernible, what range is?

In Colorado, my TJ (once I refreshed the cooling system) almost NEVER breached 210. But I got my LJ and moved to Oklahoma before summer, where the air is more dense (meaning the engine can burn more fuel and produce more heat, and has to work harder to maintain the same speed through extra aerodynamic drag), more humid (which puts 2x+ more load on the AC which dumps it's heat into the radiator) and now I can reach 230 on the highway on a hot day. It's barely a needles with past the 210 mark, but it is past it. So should I look into it or let it ride?
 
of course the sensor reading should be verified before being trusted (no different than checking an oil pressure sender before you tear into the engine to replace bearings), but once it's known good, it would be trustworthy enough in the short term to solve a problem. And if it's bad, that in itself should be addressed because the PCM is using that reading for important calculations.

The same sensor is responsible for determining the temperature for the needle on the instrument cluster. Using an OBDII is not primitive like the needle reading. Using an OBDII for live temperature readings is superior.
I know for a fact the Oil pressure uses a sensor because I replaced it to fix the reading on the instrument cluster.
 
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You'd have to define "good".
Research "Spot Ratio" with reference to IR thermometers to get a better understanding of their accuracy.

yes...they're notoriously "spotty". I would more likely verify the temp sender by pulling it out and using an OBD2 scanner to compare the PCM's temp reading against a known-good sensor in the same pot of freshly boiled water.
 
of course not, but as I stated in my previous post, the gauge is so compressed that 190-230 takes place in about 10% of the span of the gauge, so the scanner provides much better resolution. It seems like you and blaine are making the case that the extra resolution isn't needed, and I'm trying to get confirmation of that, and then an answer to, if the difference between 190 and 230 isn't significant enough to need to be discernible, what range is?
I dunno about your eyes but the sweep of the temperature gauge on its chosen range of temperatures is more than enough for my 75 year old eyes. I read various electrical meters throughout my working career in the electronics industry and I have no trouble discerning all the information I need from the OEM temperature gauge. I don't need an app for that, I would download one and use it if I did.

Not to mention I prefer analog to digital meters which is why cars and aircraft went back to analog faces (driven by unseen digital circuitry) after a short couple year long experiment with digital/numerical readout gauges in cars and aircraft was deemed a complete failure. Pilots were the first to complain and it was an uproar against numerical rather than analog gauges which are faster and easier to interpret at a glance.
 
Not to mention I prefer analog to digital meters which is why cars and aircraft went back to analog faces (driven by unseen digital circuitry) after a short couple year long experiment with digital/numerical readout gauges in cars and aircraft was deemed a complete failure. Pilots were the first to complain and it was an uproar against numerical rather than analog gauges which are faster and easier to interpret at a glance.
With the Torque Pro app that Actormike is using you can have analog, digital, needles, bars, or a combination of the above. This is what I use on my Sprinter and it is mounted in such a way that I only need to shift my eye to see it instead of peering down under the steering wheel which for me makes curvy mountain roads easier and safer. (There are a few things on a Sprinter to know about if you want to maximize engine, oil and exhaust system life).

I used a smaller version on the TJ and saw temps that the dash gauge just didn't accurately reflect. I don't use it all the time but it was handy to know, in an accurate way, what the dash gauge was saying. In some vehicles the temp gauge is stepped and doesn't move until a certain threshold is reached so you have no way to know if it is on the way up or not so you can take action early.

Then there is the scan tool capability that you always have with you in your phone for reading codes, freeze frame data and live data for things like fuel trim and O2 sensor data.

Besides that, I am a genuine nerd when it comes to this stuff and I ask you guys who disagree why can't we just have our fun? ;)

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