Everyone hears "3 row radiator" and assumes it's better, because more is better, right?

It's all about coolant flow and air flow. The engineers who built these things were pretty smart.
Indeed.

 

is it actually boiling over? those temps don't look unreasonable and could be a gauge issue? i think you might have to much technology

 

Minor update - I tried swapping out the stock style radiator with a CSF 2670 2-row copper/brass radiator. I chose this radiator because the specs seemed closest to the mopar HD 2-row that is no longer available and seems highly regarded.

After a burping session and several heat cycles, I took it on a test drive. Immediately I started getting higher temps, up to 220 degrees just merging uphill onto the freeway. I put the stock rad back in and it's back to the normal 195-200 temps.

I have a hunch that there may be air-flow issues specific to my XJ at higher speeds. The temps do not rise in stop and go and come back down when I exit the freeway. But either way, the stock radiator still outperforms everything I've tried so far, by alot.

 

*****,

What part of the country are you in? I am in Southern Nevada, and having similar problems.

Cheers!

Offio

 

I’ve been in the mountain west with the stroker — southern Idaho, Utah, Colorado. All three areas get into the mid-90s.

 

Put a second temp sensor on head somewhere or i guess even probe tge radiator you should then be able to monitor thermostat.

I think youve put 2 tstats on in this thread. This may not be enough tstat count to get a good one that works properly installed.

 

Last summer there were some 100ºF days where the XJ just couldn't shed the heat well enough (hit 235ºF). This past spring I took on a project to relocate the winch (not because I thought it would provide the required airflow through the radiator, but because I've been wanting it hidden for the past four years). In the process, I also bought a splash shield and found a Mopar 16 PSI radiator cap (the Champion came with a 13 PSI cap). Test results are in.

Mopar 195º thermostat, Mopar water pump, Mopar fans, Champion BC1193 radiator, Mopar 16 PSI radiator cap, Prestone 50/50 coolant, relocated winch, belly splash shield

• 65mph cruise
• OAT 88-91°F
• Clear and sunny
• Water temps
  • 197-199° with A/C on northbound (no efan override)
  • 203-205° with A/C on southbound (no efan override)
  • 199-203° idle no A/C, 194-196° idle no A/C and efan on
• Air temps
  • 127° IAT northbound, 136° southbound, 161° idle
  • 136° engine bay northbound, 145° southbound, 153° idle

Now, I did break my rule by applying three changes instead of one at a time, but the result yields the best temperatures yet. You may think it was the winch (previous tests without it showed negligible change), but I think the majority of the improvement came from the splash shield which seems to be forcing better airflow. I believe high speeds were creating a high pressure behind the radiator and air was flowing up from beneath the engine bay keeping the air there. Jim mentioned this earlier in the thread. Thanks, Jim!

While working on the winch relocation project, I did notice how dinged and plugged my A/C condenser is so that is next to replace.

 

Thanks for the update. Anything under 210 is a win in my experience.
I purchased a splash guard for my stroked/lifted jeep a long time ago but never put it on. I'll update the thread in the coming months when it heats up here with more findings as I think we're on to something with the air pressure issues in the engine bay. I've found that taking on steep and long grades, my temps are better in 4th+lockup than in 3rd+lockup at the same exact speed (without the stroker I could never do it in overdrive)... the increased mech fan speed is doing nothing.

 

Just bought two of those splash shields for mine because of course, they don't have them anymore. Thanks for sharing the tip!