Hairline Radiator Leaks

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GitEmSteveDave

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So last night when I got home I noticed some smoke coming out from under my hood hear the headlights. Saw leaking fluid, but it was too dark to locate the leak even with my HF light bar.

Drove to work today and popped the hood when I got there and found two leaks, both on the plastic(?) part where the main hose connects to on the drivers side. Link to photos:https://imgur.com/a/FZTStVp

So a few questions: Is this a death sentence for the radiator, or will something like Bars help? How much does replacing the radiator usually run?

and

Should the fluid be green, as in the first photo(was greener in real life)? I wonder if the dealer just threw in Glycol and not HOAT, which has me worried.

I think that since my original cap was so degraded: https://imgur.com/3ajtrfe, it probably had never been under pressure until I replaced it a few weeks ago.
 

Charlesthe2nd

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So a few questions: Is this a death sentence for the radiator, or will something like Bars help? How much does replacing the radiator usually run?

Should the fluid be green, as in the first photo(was greener in real life)? I wonder if the dealer just threw in Glycol and not HOAT, which has me worried.

I think that since my original cap was so degraded: https://imgur.com/3ajtrfe, it probably had never been under pressure until I replaced it a few weeks ago.

I may be wrong, but I think that is a death sentence for your radiator. If you need to extend its life a little then you might be able to patch it with some jb weld for plastic. Just make sure you have some more jb weld and coolant for when the next spot cracks. Also, don't use any coolant stop-leak additive, they are hell on the cooling system and will cause other things to break.

Likely right on the assumption that it hadn't been pressurized until the new cap was installed. Funny how one thing can lead to another.

When was the last time you replaced radiator hoses, hi-pressure lines, thermostat, and water pump?
 

HoosierJeeper

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Who makes an aluminum one?

Skip aftermarket plastic ones and get the Mopar one.
 

tommudd

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Use a MOPAR only
DO NOT use any crap that seals leaks unless you want to spend a lot of money later
Aluminum ones.....yes people been having issues with them, cheap china junk
 

renegade 04

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I bought my all aluminum radiator off of ebay. I know its made in china, but it works great and keeps the engine cool. My engine runs around 188-195 all day every day. And couple that with the severe duty clutch fan and also the severe duty transmission cooler with a transmission thermostat. I would be happy to provide links and also diagrams for my entire cooling system as well.
 

Charlesthe2nd

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Today makes 2 months since I bought it, so I have no idea when/if those were replaced.

Yea, it's a good idea to go ahead and check the whole system out if you're already gonna be draining the coolant to fix the radiator. Better off finding out now rather than later, because it's easier to just pay for coolant once.
 

Dayspring78

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I don’t recommend any radiator stop leak. Reason is it can cause even more problems like clogging your heater core. When that happens you have to replace the heater core which usually means tearing apart the dash to get to it.

My radiator started leaking a few months back and I bought a radiator off eBay. It was around $50 and while most of us would love to put original Mopar parts in our beloved Jeeps, some of us aren’t able to afford the parts. The radiator I purchased comes with a warranty and it’s been holding up well for the past three months. My Jeep’s temperature is right on and it looks just like the radiator that went bad in my Jeep.

Make sure you’re using HOAT coolant. I bought 3 gallons of Zerex G-05. You may want to do a flush if it has green coolant. You don’t want them to mix because again it will cause serious problems. Hope that helps! And if you need to do the water pump there’s you tube videos. It’s pretty easy, but it makes it a whole heck of a lot simpler if you remove the electric fan shroud unit.
 
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tommudd

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I don’t recommend any radiator stop leak. Reason is it can cause even more problems like clogging your heater core. When that happens you have to replace the heater core which usually means tearing apart the dash to get to it.

My radiator started leaking a few months back and I bought a radiator off eBay. It was around $50 and while most of us would love to put original Mopar parts in our beloved Jeeps, some of us aren’t able to afford the parts. The radiator I purchased comes with a warranty and it’s been holding up well for the past three months. My Jeep’s temperature is right on and it looks just like the radiator that went bad in my Jeep.

Make sure you’re using HOAT coolant. I bought 3 gallons of Zerex G-05. You may want to do a flush if it has green coolant. You don’t want them to mix because again it will cause serious problems. Hope that helps! And if you need to do the water pump there’s you tube videos. It’s pretty easy, but it makes it a whole heck of a lot simpler if you remove the electric fan shroud unit.
Buddy bought one with a warranty, 11 replacements in 2 years and he went MOPAR, then no issues, good luck with yours
 

GitEmSteveDave

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For right now I am topping her off and using my OBD reader to monitor the temp while driving. She has not gone above 202 F and hovers around 199 F while driving. After I get done with the dealership repairs, which won't cover the radiator since it's not drivetrain, I'm going to bring to a shop a friend recommended in my area to replace the radiator entirely.
 

Dayspring78

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Buddy bought one with a warranty, 11 replacements in 2 years and he went MOPAR, then no issues, good luck with yours

Honestly if I have one fail in two years I’ll replace it with the Mopar! I just couldn’t afford the Mopar one at this time. However, the Mopar one for $170 isn’t bad at all!
 

eyebooger

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Use a MOPAR only
DO NOT use any crap that seals leaks unless you want to spend a lot of money later
Aluminum ones.....yes people been having issues with them, cheap china junk


TL;DR- don’t use any of that stop leak crap!

I just went though all this (radiator). Bought my 2004 Sport back in February, when I test drove it, didn’t have much heat.

Joined the forum (First Post!), and read all youse guys experiences.

Backflushed the heater core with a garden hose, got all this rust/junk out of it. Buttoned everything back up, had worlds of heat then... for about two days. WTF? Flushed heater core again, more rust/sand in the catch bucket.

Pulled the upper & lower rad hoses flushed block thru heater hoses/water pump, and radiator. Got a BUNCH of sand/rust crap out of radiator.

Buttoned it all back up, and put my pressure tester on it- which btw, is worth every penny... radiator was leaking.

At this point I engaged my thinker, and realized the crap I was washing out was bars leak or whatever. PO had had a leak and dumped stop leak in, gumming up the heater core.

Happy ending- new Mopar radiator and t-stat, new hoses, new HOAT coolant, flushed engine w/tstat out, flushed heater core again just for funsies. No leaks, lots of heat, I’m a happy Jeepster.
 

Cardhu

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In case it wasn't obvious,

new rad mopar,
water pump (i did napa), upper and lower hose (I picked gates)
mopar thermostat

get a pile of distilled water, its about a buck a gallon and flush the system as best you can to get that green shit out. Pulling thermostat will help.

If you were doing this on a radiator that you weren't changing most recomend dropping lower rad hose instead of pet **** due to leaks and not sealing aftewards.

The water pump replacement thread has most the details you will need. No you don't' need to put that spring back in the lower rad hose(edit: see post 21/22, I've been wrong before, leave spring in new one.).

Stop leaks for quiters.
 
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LibOhToo

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If you were doing this on a radiator that you weren't changing most recomend dropping lower rad hose instead of pet **** due to leaks and not sealing aftewards.

True.

This happened to me. The course plastic threads on the petcock/plug will wear out quickly (believe it or not). Sounds crazy but it's true.

At about the 4th to 5th re-installation of the plug in my case, I could tell something wasn't the same. Visually (looking at the removed plug), you could see how the threads on the plug were failing.

I replaced with a new plug. Too late....internal threads on the radiator petcock hole itself apparently failing also.

Best to limit petcock use sparingly, e.g., for sampling fluid.
 

renegade 04

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I almost destroyed my jeeps engine when the petcock threads failed drain all the coolant from the radiator. Luckly I pulled the jeep over and shut it off as soon as i saw the temperature gauge start moving up. And then after that I ordered my all aluminum radiator.
 

GitEmSteveDave

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Thanks all for the advice. I'm probably going to end up bringing it to a mechanic to fix. If my garage wasn't being rented out for storage, I'd probably do it myself because the guy who owned it before us made it big enough to drive a bus (height wise) in each side and the floors are thick smooth concrete for a creeper. I don't have a paved driveway or anything, so there's really nowhere to evenly set up anything.

I'm def gonna go for the mopar. I figure the one in there last 15 years, so if the new one lasts 15 more, I'll never have to worry about it. I'll get a price for both just the rad and flush and rad/flush/hoses/thermo just in case. My big issue right now is time. I work ~30 minutes away and since racing season is starting, my usual back up ride is going back to work, and that limits the amount of days I can bug her for a ride b/c she ends her mornings at 10:30 and I have to be at work at 11am. If they can promise the radiator in a day, I'm going to have to agree because I'm limited to getting things done on my two days off a week right now.
 

LibOhToo

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.... the petcock threads failed drain all the coolant from the radiator.

Q: Was the petcock/plug still in place (leaking) when you discovered the problem or was the plug completely missing? Any prior service using the petcock/plug leading up to this?

Q: What transmission is in your Jeep? My reason for asking is that, if I recall correctly (or incorrectly), The Jeeps model transmission determined what particular p/n radiator was used. Please correct me if I'm wrong.
 

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