Why is my XJ overheating? Help!

Subscribe
Mar 20, 2014 | 09:42 PM
  #16  
We experimented with a HD fan clutch......promptly took it off, way too noisy, constant roar.
Reply 0
Mar 20, 2014 | 09:54 PM
  #17  
Yeah they are noisy a guy I know had one on his Cherokee but he loved it, he said it never got hot after it
Reply 0
Mar 20, 2014 | 10:28 PM
  #18  
Quote: For the past 20+ years rads have been constructed of aluminum and plastic mainly because of better efficiency.
Lighter weight, simply catering to the good ole uncle CAFE/EPA.
Reply 0
Mar 21, 2014 | 09:18 PM
  #19  
Quote: Lighter weight, simply catering to the good ole uncle CAFE/EPA.

Yep. That and cheaper cost to manufacture.
Reply 0
Mar 21, 2014 | 10:52 PM
  #20  
Quote: Lighter weight, simply catering to the good ole uncle CAFE/EPA.
Quote: Yep. That and cheaper cost to manufacture.
So tell me what's gotten lighter weight and cheaper about today's bigger 1/2 ton p/u's that have 10,000 lb tow ratings with an average cost of $41K????? Part of the reason why they can tow that much is due to a very efficient at dissipating heat aluminum rad. For the most part modern engines are smaller with more power and work harder.

Agreed, aluminum rads are lighter, cheaper and way more efficient than old school copper/brass.....sounds like a home run to me.

Your point is?
Reply 0
Mar 21, 2014 | 11:04 PM
  #21  
Quote: So tell me what's gotten lighter weight and cheaper about today's bigger 1/2 ton p/u's that have 10,000 lb tow ratings with an average cost of $41K????? Part of the reason why they can tow that much is due to a very efficient at dissipating heat aluminum rad. For the most part modern engines are smaller with more power and work harder.

Agreed, aluminum rads are lighter, cheaper and way more efficient than old school copper/brass.....sounds like a home run to me.

Your point is?



FYI:
Trucks are subject to lot less stringent CAFE.
Reply 0
Mar 22, 2014 | 07:36 AM
  #22  
Ooops. It happened again.


Another beautiful theory, mercilessly pummeled into oblivion by some nasty little fact.





Hey, Turbo, where would plastic fit on that chart?
Reply 0
Mar 22, 2014 | 08:28 AM
  #23  
After seeing that chart I ordered one custom made in pure silver. Should be ready in a few days...
Reply 0
Mar 22, 2014 | 09:26 AM
  #24  
Quote:


FYI:
Trucks are subject to lot less stringent CAFE.
Not 1/2 ton trucks.

Is your post a Geico commercial or something?

Everybody knows that.......copper has better conductivity than aluminum. The reason why all auto mfgs. went to aluminum rads is because aluminum has the ability to be shaped into very wide thin walled tubes....copper is too soft to be formed into a very wide and thin walled tube. Again, even though aluminum is not as thermal conductive as copper, a very wide thin walled aluminum tube will dissipate heat better than a narrow copper tube. If copper could be shaped into very wide thin walled tubes the same size as aluminum, then it would dissipate heat better than aluminum tubes. Very wide thin walled copper tubes will balloon from the pressure of the cooling system. To prevent the ballooning, the copper tubes would have to have much thicker walls and that would make for less efficient heat dissipation.

Again, modern aluminum rads are more efficient at dissipating heat due to their design/shape, not because aluminum is more thermally conductive.....but everybody knows that....even the green lizard.

Silver is probably like copper......to soft to build an effective designed/shaped rad......but it sure would look perty.
Reply 0
Mar 22, 2014 | 11:48 AM
  #25  
Quote: After seeing that chart I ordered one custom made in pure silver. Should be ready in a few days...

Pics or it didn't happen!
Reply 0
Mar 22, 2014 | 01:19 PM
  #26  
Quote: Not 1/2 ton trucks.

Is your post a Geico commercial or something?

Everybody knows that.......copper has better conductivity than aluminum. The reason why all auto mfgs. went to aluminum rads is because aluminum has the ability to be shaped into very wide thin walled tubes....copper is too soft to be formed into a very wide and thin walled tube. Again, even though aluminum is not as thermal conductive as copper, a very wide thin walled aluminum tube will dissipate heat better than a narrow copper tube. If copper could be shaped into very wide thin walled tubes the same size as aluminum, then it would dissipate heat better than aluminum tubes. Very wide thin walled copper tubes will balloon from the pressure of the cooling system. To prevent the ballooning, the copper tubes would have to have much thicker walls and that would make for less efficient heat dissipation.

Again, modern aluminum rads are more efficient at dissipating heat due to their design/shape, not because aluminum is more thermally conductive.....but everybody knows that....even the green lizard.

Silver is probably like copper......to soft to build an effective designed/shaped rad......but it sure would look perty.
You sure you want to keep digging? OK then,
http://www.engineeringtoolbox.com/yo...lus-d_417.html
Ultimate Tensile Strength:
Aluminum 110
Copper 220
Need more, u jus a lemme kno...
Reply 0
Mar 22, 2014 | 05:32 PM
  #27  
Yep. And let's not discuss the malleability differences.
Reply 0
Mar 23, 2014 | 01:46 AM
  #28  
screw that.. i want to see a lead radiator..
Reply 0
Mar 23, 2014 | 10:15 AM
  #29  
Quote: screw that.. i want to see a lead radiator..
The peeps that don't maintain the cooling system for XX years have one.
Reply 0
Mar 23, 2014 | 12:14 PM
  #30  
Quote: you might want to start "considering" a complete cooling system overhaul... since the weak part of our jeeps IS the cooling system...

Its relatively cheap for our jeeps, and RockAuto has everything you need...

After I did mine, it cools great...



I bought a 96 with major overheating problems.
Bought new cooling components from rockauto including the ZJ fan clutch. Prior owner had already replaced the radiator with an oem unit. I did a extended flush with distilled water and prestone flush. Reflush with distilled only, and now 50/50 coolant with distilled water. no burping required, take your time filling the radiator, squeeze the hoses, just check levels after each heat cycle. if the temp gauge fluctuates which is an indicator of air in the system shut down let cool and check levels of water / coolant. be patient during the filling process.

Temp pic is during a 30 Min Idle



Rockauto parts list.
Reply 0