Intermittent radiator leak

Ok, new radiator cap is on. I will run it a bit and see if it helps.

Also, I bought some of the constant tension hose clamps. I ordered these 1-15/32" - 1-3/4" ones, but they only will fit on the upper radiator hose radiator side. What is the recommended sizes for the other clamps? I.e. upper radiator hose engine side, and both ends of the lower radiator hose? I know I could figure it out, but I am also pretty sure one of you guys (e.g. @Chris) knows off the top of their head.

I don't actually know off the top of my head unfortunately, but if you find out, I'd like to know. If you have the other hoses off, you could measure the diameter of them to know for sure. That's what I'd do actually.

It might be nice to compile a list of hose clamp sizes if possible. I'm sure a lot of people would find that helpful.
 
I was looking into what constant tension clamps fit as my PO replaced them all with hose clamps that love to leak.. I came upon this thread on another forum:

https://bit.ly/2z9RDK1

I haven't confirmed any of the findings personally as I haven't purchased any to do the swap yet, but it seems like good info. I believe the numbers on the clamps are in mm.
 
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Ok, new radiator cap is on. I will run it a bit and see if it helps.
I ran the engine for 5-10 minutes and watched it. I think the issue is the radiator and the top seal (sorry, don't know the technical term for that).

While the engine was running, I looked around all the hoses and around the radiator cap, and didn't see any obvious leaks there.

However, I noticed antifreeze was pooling along the top of the passenger side of the radiator. It also seemed to be along the middle of the top of the radiator (though that could have just been dripping). So definitely not the side of the radiator cap. On the side of the upper hose, maybe possibly it has some leak that I'm just not seeing in the hose, but I don't think that's the case.

I've attached a few pictures of where it was leaking. But, based on that, I think I know the answer.

IMG_1474.jpg


IMG_1475.jpg


IMG_1478.jpg
 
I was looking into what constant tension clamps fit as my PO replaced them all with hose clamps that love to leak.. I came upon this thread on another forum:

https://bit.ly/2z9RDK1

I haven't confirmed any of the findings personally as I haven't purchased any to do the swap yet, but it seems like good info. I believe the numbers on the clamps are in mm.

Thanks for sharing. I also haven't verified it personally, but looks pretty specific.

EDIT:
For my 97 TJ, the info on that thread didn't match what I have. Here's what I know definitively for mine:
  • 50mm on upper hose thermostat housing - 55037990AA
  • 55mm on lower hose water pump - 55037660AA
  • 50mm on lower hose radiator outlet - 55037990AA
Note: those part numbers were what I ordered from Moparwholesaleparts.com.
 
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@Chris I have another question about your TJ Cooling System Overhaul thread.

You recommend getting a new water pump, but you don’t mention a water pump gasket. Should that be on the list too? Something like this one?
 
@Chris I have another question about your TJ Cooling System Overhaul thread.

You recommend getting a new water pump, but you don’t mention a water pump gasket. Should that be on the list too? Something like this one?

Yes. The only reason I didn't include that is because I am pretty certain most water pumps come with a gasket (mine did at least). Of course you should make sure before you order it if it does or not, because you'll definitely need a new gasket!
 
Yes. The only reason I didn't include that is because I am pretty certain most water pumps come with a gasket (mine did at least). Of course you should make sure before you order it if it does or not, because you'll definitely need a new gasket!
Ok, good to know. I’ll make sure to confirm for sure. The one I was getting is a Mopar one, so I’d hope they are doing it right. :)
 
Ok, good to know. I’ll make sure to confirm for sure. The one I was getting is a Mopar one, so I’d hope they are doing it right. :)

When I replaced mine it was an OE Mopar and it came with a replacement gasket as well.
 
Already had new radiator hoses. So good there. Will definitely get the Zerex G05.

The overall system has 84,000 miles but it’s 21 years old, so probably time to do some preventative maintenance. :)

For the other stuff I’m thinking:

Mopar 5300 6192, Engine Coolant Thermostat Housing https://www.amazon.com/dp/B004VWXH9E/?tag=wranglerorg-20

and

Stant 45359 SuperStat Thermostat - 195 Degrees Fahrenheit https://www.amazon.com/dp/B000C7YRNM/?tag=wranglerorg-20

and

Stant 25160 Thermostat Gasket https://www.amazon.com/dp/B000C847YU/?tag=wranglerorg-20

and

ACDelco 252-279 Professional Water Pump Kit https://www.amazon.com/dp/B000C9KLE4/?tag=wranglerorg-20

Do the belt, belt tensioner and idler pulley as well. Cheap and easy and you are already there. Peace of mind is worth a few extra bucks.
 
I appreciate all the input. I am a bit torn on the preventative side of things. My TJ has 84000 miles and besides the leak in the radiator everything is working fine in the cooling system. While I know that replacing everything is never a bad thing, but it is extra time and money and may not be needed for a long time.

Would it be a bad choice to just replace the radiator, radiator hoses, and the thermostat and flush the system and then do all the other stuff later?
 
I have some updated info on the clamp sizes that is different than I said before. I'll try to update later with more info and part numbers...

I ultimately replaced just the radiator and the thermostat right now. Will leave the water pump and other suggestions for some time in the future.

Upper hose, thermostat side - mine was a 50mm
Lower hose, radiator side - mine was a 50mm
Lower hose, water pump side - mine was a 55mm

Ultimately, got it all in and working. However, I did have one issue I had to work around.

I ordered a 5503-7652-AA-001 radiator. Fit like a glove for a replacement. However, one thing that didn't fit were the fan shroud bolts. The original ones I took out were 1/4"-20's. Those didn't fit the fan shroud holes on the radiator — too big. I then tried M6 bolts, also too big. I then got M5 bolts, but they were too small for the threads, so I just put a nut on the back of them, and called it good. Not awesome when I have to take them out, but a workable solution for the foreseeable future.

However, I still have a question of what the right bolts would be. Anyone have any ideas?