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XJ radiators, a review.

Just got out for an around town errand that included both some highway and stop-n-go. Without a doubt, my new setup cools better on the highway (tstat sits 1-2 steps lower in temperature than before when monitoring OBD-II), but at the same time, it cools more poorly when sitting at a stop light (temperature will steadily rise until I turn on the efan whereas before that wouldn't happen) which is an interesting dichotomy.

But of course, I made this a complicated comparison because not only did I swap radiators, I swapped a standard GMB water pump for the Hesco water pump (which is a standard GMB with the Hesco impeller), and I installed the Hesco high flow water neck. BTW, the casting for the Hesco water neck is not so great. I had to port the flow path to the cabin heater core to get it back to near stock size, and there were some nasty casting lines where the radiator hose attaches that I also had to clean up.
 
Crossing the coast range resulted in the same coolant temp rise as with the old setup. I guess this was nearly a complete waste of time from a practical perspective. Fascinating to contemplate why there was no improvement, but perhaps the simple answer is that the Summit radiator ain't so great.
 
Merely a better description of the issue than the other sites that Google brought up; not sure why you assumed I was implying they did...
 
After more time with the new setup, my opinion is somewhat revised. The new setup is definitely providing improved cooling in some circumstances. During driving today on predominantly flat roads in cool weather (about 65-70F), tstat temp consistently ran 1.5-3 deg F cooler than the old setup. Still hard to say whether its better than the old setup when subjecting the XJ to a climb at highway speeds. Still no offroad. Might get some fire road time tomorrow.

I reviewed this tread and was reminded that @Redsnake and @Weasel both installed the Summit 2-row copper-brass. Not much feedback on how well it worked though. Would be interesting to hear their feedback on long term performance.
 
1.5-3 whole degrees cooler?? Thats pretty negligible with a lot of variables wouldn't ya say? Or did I misread something?
New pump and testator right?
Of course it got a flush too?

Just saying one or all of those could be responsible for such a small margin.. the actual radiator id think be the tests you provided- hot days with ac running under load uphill pulls 4low that sort of thing.

I'm kind of reserved to just freshen up the system but keep the radiator I have, since it isn't leaking. Maybe an upgraded water pump but a flush and tstat couldn't hurt
 
I've got a Stant 180F tstat, and the tstat control temperature as read by the coolant temp sensor is 195.8F in the OBD-II data. Not sure why the control temp reported by OBD-II sits 15F above the tstat set point temp, but I saw the exact same temp difference between tstat set point and coolant temp sensor reading when I was running a 195F tstat. Kinda odd, but it seems common for XJs from what I can tell.

Anyhow, my XJ was running about 195.8-197.1F with the old setup on flat highway. Now its running 194.0-195.8F. Suggests that there is a bit more cooling capacity in the system, but overall, I agree that the improvement is minimal and could be due to factors other than the radiator. I'm contemplating trying an aluminum radiator such as the Cold Case 2-row.
 
CleanEG, can you share more on how you fabbed up the fan shroud for the SPAL? I too have the TYC fan and I suspect it is not doing it's job. Seems like it doesn't run properly. I ordered up the KSuspension fan switch harness and would like to upgrade to a SPAL in place of the TYC.

Hi Chuck,

I just went to my local metal supply store and picked up some aluminum sheeting. I then used a cheap brake from Harbor Freight to cut and bend it into a shroud. Using a jig saw with a metal blade, I cut a hole for the fan and then used a rivet gun to rivet the fan to the shroud. I'll take some pictures when I take it out to swap the radiator.
 
Here's some pictures of the fan shroud for the spal fan. I also included a picture of my Mishimoto drain plug after driving 1500 miles since the last full flush. As you can see, plenty of crud on there that was probably blocking the tubes. I just replaced the Mishimoto with the Spectre, so we'll see how well it performs over the next month or so. Just did another full flush, so we'll see.

p1LDMG8bHd7Crc1o7
 
Cal, if you are going to run the Cold Case let me suggest you do several things: First, ditch the O-ring for the Renix sensor in the tank. There is no support for the outside of the O-ring. It will blow out. Either put in a metal backed seal, a soft aluminum washer seal or just seal the plug directly to the tank.

Secondly, flush the radiator several times before you install it. These radiators are full of metal shavings. I expect they are the product of cutting the cores. I wouldn't be surprised if they are the reason so many Mishimotos end up being plugged.

Finally, expect to need to re-seal the overflow fitting at the radiator cap. Whoever is assembling these things must be racing a work quota. They only thread them in a few turns.

Beyond those things, don't expect to fit a ZJ clutch. I found installation went smoother if I improved the chamfer on the pins that drop into the radiator support at the bottom. I also ditched the drain ****. Planning ahead and ordering an aluminum plug (3/8 NPT IIRC) might be best.

And it may be that you already know the above from my own posts on the topic, but the info may be useful to someone else.

Edit to add: Somehow I never before noticed that we have nanny control software. Make that a "drain rooster", or maybe "draincock" will sneak by...

Anak, a couple of questions:

- If you bought an Al crush washer for the Renix temp sensor, do you have a link or PN that you can post for the item?
- Is the drain really 3/8" NPT? I would have expected it to be 1/4" NPT, and one of your earlier posts says 1/4" NPT.
- What was your procedure for removing the Al shavings from the radiator? Maybe shake it around a bunch to remove some debris, then flush with garden hose?
- If you have an autotrans, were you able to successfully use the lower adapter for the transcooler line? Some people have said that the diameter is too large for the quick disconnect to fit.
 
Anak, a couple of questions:

- If you bought an Al crush washer for the Renix temp sensor, do you have a link or PN that you can post for the item?
- Is the drain really 3/8" NPT? I would have expected it to be 1/4" NPT, and one of your earlier posts says 1/4" NPT.
- What was your procedure for removing the Al shavings from the radiator? Maybe shake it around a bunch to remove some debris, then flush with garden hose?
- If you have an autotrans, were you able to successfully use the lower adapter for the transcooler line? Some people have said that the diameter is too large for the quick disconnect to fit.

I don't have a PN for the AL washer. I bought an assortment from either Scamazon or Fleabay. The assortment doesn't have even have a PN on it. Its label says "SWPEET Aluminum Flat Washer Assortment 470 pcs". The bar code is "X001UVPMIJ". What Cal did just sealing the plug directly to the radiator is probably fine. I doubt that would void the warranty.

You are right about the drain plug--1/4" NPT. Sorry about that. I do have a PN for that one: Summit G1486B (the "B" being for blue).

Rinse and shake was the best I could do for the AL shavings. I am collecting pieces to run a coolant filter.

Sorry, no auto trans. I have an AX-15.
 
Thanks. Do you remember which of the Swpeet washers fit?

Considering that Cold Case is positioning themselves as an affordable top shelf radiator, its rather surprising that there were shavings in yours. Will be interesting to see how much is in the one I receive.
 
I think M22x29


M22 being the ID, M29 being the OD.


ColdCaseFittingSealFix5OPT.jpg


Note: IIRC I installed that washer with the radiator in a horizontal position because the washer will not self center properly. There are washers with a rubber center which would self center, but they are made of steel and I don't trust the comination of metals.
 
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Well, I've got a Cold Case on the way, so I'll be doing a one-to-one comparison to the Summit Copper/Brass. Its arriving Thursday, so the hope it to install it this weekend. Now that I've ripped the cooling system apart once, it should be pretty quick to just do the radiator, especially since Anak has pointed out the issues with the Cold Case, so I can be ready.
 
Hi Chuck,

I just went to my local metal supply store and picked up some aluminum sheeting. I then used a cheap brake from Harbor Freight to cut and bend it into a shroud. Using a jig saw with a metal blade, I cut a hole for the fan and then used a rivet gun to rivet the fan to the shroud. I'll take some pictures when I take it out to swap the radiator.

That looks excellent, and exactly what I was wanting to do! Thank you!
 
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