Improving the cooling on our TJs

[Jcrubicon]

Dang man. I have two coolers in front of the condenser, but I haven’t seen mine get that high. I don’t rely on the gauge either. Is your fan clutch pulling sufficient air? If you have a meter for checking CFM we can compare if you’re interested.

I’ve have flakes plug up a newish Mopar radiator but that also showed high temps when sustaining a fast highway speed.

I can assure the radiator is not clogged (less than a month old) and fan clutch works properly (new one installed yesterday) I don’t have a meter but can definitely get one. What meter do you have? Also to properly test that we would need to replicate conditions as close as possible.

 

[MikeE024]

I can assure the radiator is not clogged (less than a month old) and fan clutch works properly (new one installed yesterday) I don’t have a meter but can definitely get one. What meter do you have? Also to properly test that we would need to replicate conditions as close as possible.

I hope so. I replaced my entire system with Mopar parts, and it still happened within a month because the block was shedding flakes (even after I Thermocured the system).

I now run two Aeroforce OBD II gauges that work with the 05/06 PCM.

 

[Jcrubicon]

I hope so. I replaced my entire system with Mopar parts, and it still happened within a month because the block was shedding flakes (even after I Thermocured the system).

I now run two Aeroforce OBD II gauges that work with the 05/06 PCM.

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Who knows maybe I have a cracked head or head gasket problem that’s the only thing I haven’t tried I’ve been chasing this for the last couple years my coolant isn’t disappearing though and nothing is mixing

 

[MikeE024]

Who knows maybe I have a cracked head or head gasket problem that’s the only thing I haven’t tried I’ve been chasing this for the last couple years my coolant isn’t disappearing though and nothing is mixing

Wouldn't the coolant go to your oil, coolant bottle, or exhaust if that was the case? Seems like that should be ok if you aren't losing coolant.

I've had the flake issue come and go over time. I was just looking into this annoyance and ordered an inline screen in hopes to not need to black flush the radiator as often as I have been. The engine works well as a whole so I have not plans to to remove it over this issue.

 

[Jcrubicon]

Wouldn't the coolant go to your oil, coolant bottle, or exhaust if that was the case? Seems like that should be ok if you aren't losing coolant.

I've had the flake issue come and go over time. I was just looking into this annoyance and ordered an inline screen in hopes to not need to black flush the radiator as often as I have been. The engine works well as a whole so I have not plans to to remove it over this issue.

I’ve never had any issues with flake in my cooling system. I also have an 05-06 though so I will double check and I agree the head gasket definitely doesn’t make any sense but that’s all I have left at this point. What CFM meter do you have? I would like to buy one to compare airflow results especially with the 19 inch 6 blade fan I put in.

 

[MikeE024]

@Jcrubicon I bought this in 2016 for a project and then used it later comparing different fans on my 454 dually. I'd check around to see if there's a better device or better deal. Mine has been used sparingly but it has worked well.

 

[MikeE024]

I’ve never had any issues with flake in my cooling system. I also have an 05-06 though so I will double check and I agree the head gasket definitely doesn’t make any sense but that’s all I have left at this point. What CFM meter do you have? I would like to buy one to compare airflow results especially with the 19 inch 6 blade fan I put in.

Have you tried a different fan clutch? The fan difference won't matter much if the clutch isn't properly engaged. Just throwing that out there after replacing a fairly new Mopar clutch with this Hayden due to having issues (I never figured the Mopar clutch would cost 4x, yet fail like a cheaper part).

Edit: The clutch fits our rig, Amazon's system is wrong...it's very similar in profile to the Mopar I installed

 

[Jcrubicon]

@Jcrubicon I bought this in 2016 for a project and then used it later comparing different fans on my 454 dually. I'd check around to see if there's a better device or better deal. Mine has been used sparingly but it has worked well.

Just ordered something similar should be delivered in the next 5 hours once I get it, I’m going to take some measurements from the left, right and center of the grill 1-2inches away from it my AC will be on it’s max setting and the Jeep will be already at operating temperature to ensure the fan clutch is engaged

 

[Jcrubicon]

Have you tried a different fan clutch? The fan difference won't matter much if the clutch isn't properly engaged. Just throwing that out there after replacing a fairly new Mopar clutch with this Hayden due to having issues (I never figured the Mopar clutch would cost 4x, yet fail like a cheaper part).

Edit: The clutch fits our rig, Amazon's system is wrong...it's very similar in profile to the Mopar I installed

Let’s see I’ve tested
Hayden 2771(hd) 2791(severe)
usmw 22159(severe) and 22160 (hd)
The US motor Works clutches, have functioned far superior to the hayden clutches that I’ve had for some reason those all failed in short order permanently locking on no matter what temp outside (4 different ones). The US motor Works clutches are also made here in the US, which is good to see while Hayden’s manufacturing has moved to Mexico. The severe duty clutch from US motor Works (22159) is in my closet because it’s too aggressive for this fan way too noisy and to much drag on the engine I was running it on the stock fan np though.

 

[MikeE024]

Let’s see I’ve tested
Hayden 2771(hd) 2791(severe)
usmw 22159(severe) and 22160 (hd)
The US motor Works clutches, have functioned far superior to the hayden clutches that I’ve had for some reason those all failed in short order permanently locking on no matter what temp outside (4 different ones). The US motor Works clutches are also made here in the US, which is good to see while Hayden’s manufacturing has moved to Mexico. The severe duty clutch from US motor Works (22159) is in my closet because it’s too aggressive for this fan way too noisy and to much drag on the engine I was running it on the stock fan np though.

I think you've sufficiently looked into the clutch route.

My USMW failed from the go, so I went to the Hayden that I linked above.

 

[Jcrubicon]

I think you've sufficiently looked into the clutch route.

My USMW failed from the go, so I went to the Hayden that I linked above.

Let’s just say I can change the damn things at record setting speeds what failure did you have with yours? I had one leaking oil in the box when I went to go pick it up so I had them order a new one. Btw autozone by me (Chicago area) duralast brand is usmw 22160 oreillys uses Hayden clutches for there master pro brand.

 

[MikeE024]

Let’s just say I can change the damn things at record setting speeds what failure did you have with yours? I had one leaking oil in the box when I went to go pick it up so I had them order a new one. Btw autozone by me (Chicago area) duralast brand is usmw 22160 oreillys uses Hayden clutches for there master pro brand.

Me too man, I even modified a tool from Amazon so I have my own little removal set-up now. (and now I'll never need to change it bc I have the tool)

Which Hayden unit does Oreillys use?

Almost all places call for the 2771 for our TJs. Members in the past confirmed that the 2791 works as well and is supposed to last longer than the 2771. Their engagement numbers are similar...differ by about 5% iirc.

I have the 2791, which is not listed for the TJ even though it works and looks exactly like my Mopar unit I removed.

 

[Ericshere03]

Did some testing today at 85f with the 19in fan and usmw 22160 fan clutch after 45 mins of idling and the ac on full blast she topped out at 210! Massive improvement! so far this is looking promising! Tomorrow will be in the 90s I will post again with this results. Cheers!

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Call me when you try this at 120+ degrees … fully idling doesn’t stress the system much. I vote go on a 10min freeway drive, 75+ mph. THEN idle.

Also, all my TJ/LJs were fine in the AZ desert heat. I’d see the gauge creep above the mid point 210 indicator, but that’s it.

I currently run a new Mopar fan clutch, stock fan, Mopar water pump, ported thermostat housing, ‘real’ 195 degree Robert Shaw thermostat and a Cold Case aluminum radiator. 110 (hottest it’s been so far) AC and idling, freeway, stop and go (real driving) and the temperatures may creep to the 210 indicator at most. Best performance I’ve seen in my 6 TJ/LJ Jeeps.

I may have said this but to reiterate the lessons of the TJ cooling system………….

Stant Superstat used to give rock solid temperatures, but they’re not crap and you’ll see fluctuations.

Same for Mopar!!!

Robert Shaw from Flowkooler offered tremendous stability.

Mopar fan clutch it perfect, starts to lock up when idling and releases when speed is underway (in 100+ weather)

I’m not sold on the porting of the thermostat housing, but I am NOT dissatisfied, and the cost isn’t bad.

Mopar Radiator is great! Actually, looks like a Autozone China special, but it works quite well, however, this cold case is better. I see lower peak temperatures and slower water temperature creep plus it looks beautiful with OEM-esque pressed tanks, not fabricated Lego designed like champion (I’ve used them twice).

Hayden fan clutches “work” and do OK, but the severe duty is too aggressive and causes the belt to slip above 3000-3500rpm, this is with new belts, pulleys and tensioner. But you can bet your pushing the fan to the limit, the heavy duty seems to be weaker than the Mopar, but the Mopar fan clutch falls right in the middle.

Stay away from silicone hoses, cheap rubber hoses are disappointing… Mopar radiator hoses are beefy, well made and have a few more intricate bends.

Throw your worm clamps the trash, buy constant tension clamps from the dealer or bel-metric, they last, they never ever leak.

Flush your engine block! Remove the drain from your engine block and run a ton of water, you’ll see all sorts of stuff come out, “stuff” doesn’t cool your motor. Replace plug with a brass plug for the future.

 

[MikeE024]

Also, all my TJ/LJs were fine in the AZ desert heat. I’d see the gauge creep above the mid point 210 indicator, but that’s it.

Your stock gauge isn't telling you what you think it is.

I've seen my coolant gauge on the A-pillar read 220 when the stock gauge was to the left of the 210 needle and seen the stock needle well to the right of the 210 needle when my PCM was reporting 204. Anyone running a legit gauge knows that the stock gauges isn't useful for determining the actual real-time temperatures.

I currently run a new Mopar fan clutch, stock fan, Mopar water pump, ported thermostat housing, ‘real’ 195 degree Robert Shaw thermostat and a Cold Case aluminum radiator. 110 (hottest it’s been so far) AC and idling, freeway, stop and go (real driving) and the temperatures may creep to the 210 indicator at most. Best performance I’ve seen in my 6 TJ/LJ Jeeps.

You don't know your actual ECTs if you are using the stock gauge to get your info.

I'm seeing 210* ECTs at most right now as well with the turbo in the desert heat. My ETCs would be higher if tracked them while driving 85mph from Tucson to Phoenix.

Mopar fan clutch it perfect, starts to lock up when idling and releases when speed is underway (in 100+ weather)

Usually, but not always.

Mine was new and shit from the beginning, but I didn't know the bearing noise came from it and not any of the pulleys until I changed them all and bypassed the AC compressor.

I’m not sold on the porting of the thermostat housing, but I am NOT dissatisfied, and the cost isn’t bad.

I doubt that's required...you could test the housing's flow by running a lower thermostat or no thermostat at all and see if you overheat on the highway or in idle afterwards.

Hayden fan clutches “work” and do OK, but the heavy duty is too aggressive and causes the belt to slip above 3000-3500rpm, this is with new belts, pulleys and tensioner.

I run up to 3700 often with the turbo and don't have a single issue with the 2791. My Mopar unit was seizing around 3500-3600 like clock work, but I thought it was a pulley and not the newish clutch. No issues except for 3600. Glad that's behind me because I play in that area often now.

Stay away from silicone hoses, cheap rubber hoses are disappointing… Mopar radiator hoses are beefy, well made and have a few more intricate bends.

The hoses are the least of my concern to go Mopar on. Gates, Continental, AC Gold have never been a problem for me. The Gates lower hose is $24 and the Mopar is $153...feel free to get it if you want.

Throw your worm clamps the trash, buy constant tension clamps from the dealer or bel-metric, they last, they never ever leak.

Flush your engine block! Remove the drain from your engine block and run a ton of water, you’ll see all sorts of stuff come out, “stuff” doesn’t cool your motor. Replace plug with a brass plug for the future.

Replace it with steel so you don't have galvanic corrosion. I use a hex bit and that's a game changer...I drop the fluid from the block for every flush round and I do many after using Thermocure. The hex bit stays on the bit as you fish your extension between the Pre-cats. It takes me about 30 seconds to remove and a little over one minute to install. Regrettably, I've done it a ton to get that fast. The extenion length you want is about 12-13". You won't regret going to a hex bit plug if you make the switch bc the 8mm square socket doesn't hold onto the plug nearly as well for install.

 

[Ericshere03]

Your stock gauge isn't telling you what you think it is.

I've seen my coolant gauge on the A-pillar read 220 when the stock gauge was to the left of the 210 needle and seen the stock needle well to the right of the 210 needle when my PCM was reporting 204. Anyone running a legit gauge knows that the stock gauges isn't useful for determining the actual real-time temperatures.



Get a real ETC gauge then your opinions will be useful.

I'm seeing 210* ECTs at most right now as well with the turbo in the desert heat.



Usually, but not always.

Mine was new and shit from the beginning, but I didn't know the bearing noise came from it and not any of the pulleys until I changed them all and bypassed the AC compressor.



I doubt that's required...you could test the housing's flow by running a lower thermostat or no thermostat at all and see if you overheat on the highway or in idle afterwards.



I run up to 3700 often with the turbo and don't have a single issue with the 2791. My Mopar unit was seizing around 3500-3600 like clock work, but I thought it was a pulley and not the newish clutch. No issues except for 3600. Glad that's behind me because I play in that area often now.



The hoses are the least of my concern to go Mopar on. Gates, Continental, AC Gold have never been a problem for me. The Gates lower hose is $24 and the Mopar is $153...feel free to get it if you want.



Replace it with steel so you don't have galvanic corrosion. I use a hex bit and that's a game changer...I drop the fluid from the block for every flush round and I do many after using Thermocure. The hex bit stays on the bit as you fish your extension between the Pre-cats. It takes me about 30 seconds to remove and a little over one minute to install. Regrettably, I've done it a ton to get that fast. The extenion length you want is about 12-13". You won't regret going to a hex bit plug if you make the switch bc the 8mm square socket doesn't hold onto the plug nearly as well for install.

The gauge is telling me exactly what I think it is, actually. It’s painting a pretty picture that everything is ok as not to alarm the average ignorant driver… almost as bad as the oil “gauge” … regardless of it’s inherent inaccuracy, you can characterize the cooling systems behavior based on the needles position and behavior (swaying). It would be more meaningful if you replaced the numbers on the gauge with; cold, warm and hot.

An ECT gauge would be helpful, but more for curiosity. I have 100’s of thousands of miles on these TJ’s over my 18 years of driving them I know for certain that everything less than a couple needlewiths over the 210 dot is a-ok, whether or not it’s really 210, 230 or whatever means nothing to me. I been thinking of someday swapping a Hemi or LS, that would be a good time to put real gauges that tell me real data.

Well obviously a defective fan clutch out of the box is a poor indicator of the function of a properly built fan clutch, just throw that mental data point away. But I am surprised that your Haden sever duty didn’t squeal your belt. It would only do it when fully locked up. I kept it because I’m not often in that rev range and at the time kept me cool with a Mopar radiator, I was happy and AC was always cold.

I’ve never overheated a TJ, EVER, so I cannot comment on the high flow housing being effective … HOWEVER this same LJ was initially running a Mopar thermostat and stock housing, the needle danced around the 210, eventually would stabilize a needle width or so beyond 210 (this tells me thermostat was wide open) when I got tired of hoping the Mopar thermostat would start to behave I swapped it for a Robert Shaw and high flow, changed nothing else and not only did the dancing needle become rock solid, but the peak temperature came down to about 1 needle with below the 210 dot. Assuming both thermostats were wide open, it seems the additional flow increased cooling capacity.

I’ll keep my brass, how many galactic corrosion issues do you see with brass sensors in an engine? I’ve had 40-50 year old corvettes with brass sensors and they come right out, no corrosion. Steel on the other hand has a nasty habit of seizing, the stock plugs on any engine I mess with is a PITA to remove.

 

[MikeE024]

The gauge is telling me exactly what I think it is, actually.

You can't claim what temperatures you are running at. You might was well just say that you are in a safe range and that's all you know.

An ECT gauge would be helpful, but more for curiosity. I have 100’s of thousands of miles on these TJ’s over my 18 years of driving them I know for certain that everything less than a couple needlewiths over the 210 dot is a-ok, whether or not it’s really 210, 230 or whatever means nothing to me. I been thinking of someday swapping a Hemi or LS, that would be a good time to put real gauges that tell me real data.

I wouldn't tell people how superior your system works when you don't have any input that looks any better than a proper running Mopar system.

My two Motorad thermostats have different results...one hangs around 195 more (dropped to 193) and the other doesn't hang around 195 nearly as much (or drop below that). Some open sooner and more than others, which is pretty annoying.

Well obviously a defective fan clutch out of the box is a poor indicator of the function of a properly built fan clutch, just throw that mental data point away.

Mine worked fine except for at high RPMs.

A Mopar clutch isn't guaranteed to work as it should, and once we know that to be a fact, we know it's wise to not speak in absolutes where it's not accurate.

Also, do we throw away that mental data point when a Hayden or USMW doesn't work out of the box? Not if we're smart.

But I am surprised that your Haden sever duty didn’t squeal your belt. It would only do it when fully locked up. I kept it because I’m not often in that rev range and at the time kept me cool with a Mopar radiator, I was happy and AC was always cold.

That sounds similar to what my Mopar clutch did. All was good until I was revved up and it didn't matter to me much at the time because I was rarily in that range.

But adding the turbo reminded me that I needed to solve the issue. Everyone pointed to the idler/tentioner pulleys but I had already changed them, then bypassed the AC compressor, then changed the alternator...then I changed the clutch without telling anyone bc I didn't want to discuss it. And it solved it. How annoying,

I’ve never overheated a TJ, EVER, so I cannot comment on the high flow housing being effective … HOWEVER this same LJ was initially running a Mopar thermostat and stock housing, the needle danced around the 210, eventually would stabilize a needle width or so beyond 210 (this tells me thermostat was wide open) when I got tired of hoping the Mopar thermostat would start to behave I swapped it for a Robert Shaw and high flow, changed nothing else and not only did the dancing needle become rock solid, but the peak temperature came down to about 1 needle with below the 210 dot. Assuming both thermostats were wide open, it seems the additional flow increased cooling capacity.

I've read conflicting results on the Robert Shaw, but I'm game to try one. I just don't because I have a Mopar (motorad) and a spare. I'm a sucker for an experiment though so I may get one one of these days.

I’ll keep my brass, how many galactic corrosion issues do you see with brass sensors in an engine? I’ve had 40-50 year old corvettes with brass sensors and they come right out, no corrosion. Steel on the other hand has a nasty habit of seizing, the stock plugs on any engine I mess with is a PITA to remove.

You bring up brass sensors, but how many of them are in the presence of the key ingredient that causes galvanic corrosion...an electrolyte solution? The reactions from electrolysis are why we have to pay attention to the quality of our coolant. That's not something I'm worried about with many other sensors.

Keep brass if you want. I also have no issues with my steel.

But, I highly recommend going with a hex bit style plug...no need to thank me when you are very happy with the ease of installation. I would hate draining my block if I was still using the 8mm square plug.

 

[MountaineerTom]

I’ll keep my brass, how many galactic corrosion issues do you see with brass sensors in an engine?

That’s some serious corrosion.

 

[Jcrubicon]

Me too man, I even modified a tool from Amazon so I have my own little removal set-up now. (and now I'll never need to change it bc I have the tool)

Which Hayden unit does Oreillys use?

Almost all places call for the 2771 for our TJs. Members in the past confirmed that the 2791 works as well and is supposed to last longer than the 2771. Their engagement numbers are similar...differ by about 5% iirc.

I have the 2791, which is not listed for the TJ even though it works and looks exactly like my Mopar unit I removed.

They use the same part numbers as Hayden they carry both.

These are the wind speed numbers I got on the meter lmk what you think. I had the meter against the grill meter shows 97f as the temperature of ambient air those numbers were also pretty consistent across the whole grill from 5-6 mph this was after heat soaking the system and ac full blast idling for 30mins ect at 215f

 

[Ericshere03]

You can't claim what temperatures you are running at. You might was well just say that you are in a safe range and that's all you know.




I wouldn't tell people how superior your system works when you don't have any input that looks any better than a proper running Mopar system.

My two Motorad thermostats have different results...one hangs around 195 more (dropped to 193) and the other doesn't hang around 195 nearly as much (or drop below that). Some open sooner and more than others, which is pretty annoying.



Mine worked fine except for at high RPMs.

A Mopar clutch isn't guaranteed to work as it should, and once we know that to be a fact, we know it's wise to not speak in absolutes where it's not accurate.

Also, do we throw away that mental data point when a Hayden or USMW doesn't work out of the box? Not if we're smart.



That sounds similar to what my Mopar clutch did. All was good until I was revved up and it didn't matter to me much at the time because I was rarily in that range.

But adding the turbo reminded me that I needed to solve the issue. Everyone pointed to the idler/tentioner pulleys but I had already changed them, then the AC compressor, then the alternator...then I changed the clutch without telling anyone bc I didn't want to discuss it. And it solved it. How annoying,



I've read conflicting results on the Robert Shaw, but I'm game to try one. I just don't because I have a Mopar (motorad) and a spare. I'm a sucker for an experiment though so I may get one one of these days.



You bring up brass sensors, but how many of them are in the presence of the key ingredient that causes galvanic corrosion...an electrolyte solution? The reactions from electrolysis are why we have to pay attention to the quality of our coolant. That's not something I'm worried about with many other sensors.

Keep brass if you want. I also have no issues with my steel.

But, I highly recommend going with a hex bit style plug...no need to thank me when you are very happy with the ease of installation. I would hate draining my block if I was still using the 8mm square plug.

Yes I have a hex style for access but brass … the sensors I was referring to were water temperature sensors and various others that plug into water jackets in both aluminum and cast iron. If I can get 50-75 years in a brass sensor (and VSV valves) in a water jacket, then I’m not worried in the least about my TJ. I’ll take the ease of removal over any galvanic concerns. There is also a galvanic potential table you should look at, I believe brass on aluminum will corrode the aluminum and brass on cast iron will corrode the brass. You don’t see brass freeze plugs failing routinely, do you?

I have enough inout from the stock gauge, I know the gauge isn’t accurate and I know they apply a bell curve to make it stay near “normal” but I been looking at these gauges for 18 years, I know what’s warming up, normal, warmer than normal, I can characterize when the thermostat is full open. Also, AC performance is affected by things such as fan performance (clutch and blades) as well as radiator heat saturation, a cooler radiator helps the AC get I bit cooler.

So the Robert Shaw conflict comes from the fact that we have Chinese knockoffs … I have a small stockpile of real American made Robert Shaw stats, all tested and put on my shelf. My chevys and TJs all use the same ones, so it makes sense to keep them on hand.

If your a science guy and clearly have the digital readout, I’d like to see you upgrade to a Robert Shaw, take measurements of peak temperature as well as characteristics of how fast your jeep somes up to temp, how steady the coolant temps are controlled, etc. I’ll even order you a stat for this data. Then as a final experiment, repeat with a high flow thermostat housing.

Again, I don’t think your Mopar was working, as far as I know, I never had a defective Hayden, typically the failure mode for these things are that they loosen up, not overtighten…

And I don’t say much more than “my jeep is at a safe temperature” l, I realize our dumb downed gauge readings, but they are consistent. Like I said, take the numbers out of the equation, perhaps keep 210 but label it 210-ish … you can see when you have a thermostat stuck open, takes forever to warm up, and runs cold (I bought a Jeep once without a thermostat). I can tell brand of thermostat by the needle. I bought another Jeep with a French thermostat and the needle behaved uniquely. So to say it can only confirm proper temperature is false, but the truth isn’t far off.

 

[MikeE024]

They use the same part numbers as Hayden they carry both.

These are the wind speed numbers I got on the meter lmk what you think. I had the meter against the grill

View attachment 534853

View attachment 534854

View attachment 534855

I was taking my readings from behind the fan on my truck. Checking at the grill might be better and it's certainly safer.

My reading from the grill might not be proper to compare to since I have two coolers in front of the condenser. But I'll check from the grill and then near the thermostat housing and send you what I find.