Just got the KJ back from the shop. Still Getting hot at highway speeds.

[Tech-Mechanic]

I put a new radiator, water pump, thermostat and hoses on my Jeep earlier this week. I was not having cooling issues before the repair. I changed the parts because the radiator had a bad leak, and the water pump worked ok but was seeping a little around the seal.

I bought the car in November, and wasn't sure what type of coolant it had in it so, I decided to flush the radiator. Had a heck of a time getting all the old stuff out. I ran about 12 gallons of distilled water through it to get it to start coming out clear. And an equally difficult time getting the new anti-freeze in. I couldn't get the solution to the right mix because I couldn't cycle enough of the water out. Plus, it did fine just driving it around town but, when I took it up to highway speeds it started getting hot. After trying to get the air out of the system for two days using a no-spill funnel kit, I finally said uncle and took it to a shop to have them do a complete flush and refill.

Just picked it up about an hour ago, and still the same issue. Does fine around town when you're driving under 45 but, take it out on the road and it starts getting hot. I assume the shop wasn't successful in getting the air pocket out. In which case, I can probably just go back Monday and have them fix it. (I did tell them it only gets hot over 2,000RPMs but, I'm betting they just took it on a short drive in town) I know Libertys are known to have cooling issues so, I'm wondering if anyone has any other suggestions as to what could be going on? Do the sympoms I've described sound like air in the system or should I be looking elsewhere? As I said, no cooling issues before the parts changes, the job was done to stop leaks.

Thanks in advance for your time.

 

[tommudd]

Sounds like air in there yet
Sometimes it takes a long while with a lot of hat throwing , saying words your mother would wash your mouth out for to get it

 

[Tech-Mechanic]

Sounds like air in there yet
Sometimes it takes a long while with a lot of hat throwing , saying words your mother would wash your mouth out for to get it

Well, let's hope that's the case...
I took it out and drove it again. Still no issues at lower speeds. I took it out on the highway again and it didn't start to get hot until I turned the heater fan down to 1.
Didn't get as hot as it did earlier today. And started to cool down a bit again when I turned the blower back on. So, yeah the symptoms line up with being low on coolant.
But, I'm P.O.'d after looking under the hood... I asked the guy at the shop what kind of antifreeze they used. He said they used "Gold". (he didn't specify HOAT, but I assumed that was the case, since every automotive site I go to recommends the HOAT gold for 2000 - 2012 Chrysler) But, when I looked under the hood to see if it had pulled anything out of the reservoir, I saw that the stuff that's in it is blue! That's not right, is it?
I guess if they truly flushed the system, you can put anything you want in there, but if they couldn't get the air out, then I'm not confident they got all the old coolant out either. I may have mixed fluids.
Now I'm worried but, they're not open til Monday so, can't do anything about it til then.

 

[uss2defiant]

color doesn't necessarily mean anything but you can't just use any type of antifreeze either after a complete drain and flush.

 

[LibertyTC]

Ya the Jeep definitely needs Hoat or Zerex G-05 only. Did you use a Mopar 195 degree thermostat?
Once cold overnight, see if the coolant is at or below the cold line on reservoir tank. If it's low, add some back to cold line. (May have to repeat a few days)
To get air out, slightly crack the air bleeder slightly open when HOT-- til no bubbles are seen, then close it. see images below.
Use the correct tool to break it free, air bleeder hex, located at top rad hose. Keep centered and use downward force to break it free, don't strip it.
You can also cold fill at bleeder with a small funnel initially.

 

[LibertyTC]

Did not realize you were online, refresh as I may have just edited in extra comments. THX

 

[Tech-Mechanic]

Ya the Jeep definitely needs Hoat or Zerex G-05 only. Did you use a Mopar 195 degree thermostat?
Once cold overnight, see if the coolant is at or below the cold line on reservoir tank. If it's low, add some back to cold line. (May have to repeat a few days)
To get air out, slightly crack the air bleeder slightly open when HOT-- til no bubbles are seen, then close it. see images below.
Use the correct tool to break free the air bleeder hex, located at top rad hose.
You can also cold fill from there with a small funnel initially.

Thanks for that advice. I didn't use a Mopar thermo. I used Gates, which have served me well in the past, although I don't see anything on the packaging or the website I bought it from that mentions the temp rating. It does have a vent on it which I'm pretty sure I put at or very near the top.

That bleeder valve wrench sounds like a handy tool. I'll probably pick one up but, I don't want to add anything yet because I'm not sure what they used. Same with the thermostat it would be easy enough to change out with a Mopar part but, I'd lose more coolant, and I don't know what kind to add.

I did test the solution and the tester says it's good to like -40 so, at least they got that right... That's the only reason I took it to a shop. I would have tried to work it out myself but, I couldn't get the mix right. I tried using the Peak gold antifreeze but, because I couldn't cycle enough of the water out, I couldn't get the solution to test better than -10°F. It's supposed to be -7° here on Monday so, that's a margin I didn't want to mess with. Also, with the air pocket, I wasn't sure if it was circulating properly, and wasn't convinced what I was testing at the radiator cap was representative of what was actually in the block. So I decided just to pay a couple hundred bucks and have it done "right", and this is where that got me.

At any rate, now that I've paid someone to do it, it's their problem... At least until I lose confidence in them. I've used this place several times over the last few years but, never for anything major. But, they've always done decent work and have been fair. (This is the first time I've taken the Jeep there. My last car was a Subaru and it rarely needed maintenance) I'm going back over there Monday and see if they can burp the rest of the air out and see what they have to say about the fact that they told me they put "gold" coolant in but when I opened the hood it was blue.

 

[tommudd]

Live and learn, some lessons cost a lot though

 

[LibertyTC]

Get the Mopar thermostat in hand first (not expensive) & then do the Hoat coolant together. (also a good time to consider Mopar hoses ?)
The Mopar has an air bleed hole and built in gasket.
Note correct orientation.

 

[Tech-Mechanic]

Get the Mopar thermostat in hand first (not expensive) & then do the Hoat coolant together. (also a good time to consider Mopar hoses ?)
The Mopar has an air bleed hole and built in gasket.
Note correct orientation.

I made sure to take lots of pictures as I was taking things apart. So I did get the thermo' installed in the right direction. I put the vent in the exact same orientation as the one it had in it which was about at the 1 o'clock position. It wasn't getting hot with the old one so I assume that's close enough.
The old one wasn't bad. Maybe I'll put that one back and see if it changes anything. But, I gotta talk to the shop first about the coolant they used.

 

[LibertyTC]

Was the old one a mopar thermostat?

 

[JeepJeepster]

Getting warm only when putting the engine under load sounds like a cooling capacity issue to me... This is backed up by the fact that it doesnt overheat when you have the interior heat on.

Either you have some sort of blockage, which would be odd at this point, or that tstat isnt fully opening..... I would install a mopar tstat before wasting anymore time. This is assuming the 'new' water pump is good.

Idk what year vehicle youre working on, but the pre-2007 is pretty much self bleeding with the hose running from the radiator to the coolant tank. Fill it up with the bleed s-crew removed till coolant comes out, then cap it and youre done. This doesnt apply to the 2007 KJ or the 4.7 WJ engine. Ive struggled to bleed a 4.7 in a WJ, even with the big funnel you can use to burp them.

 

[Tech-Mechanic]

Getting warm only when putting the engine under load sounds like a cooling capacity issue to me... This is backed up by the fact that it doesnt overheat when you have the interior heat on.

Either you have some sort of blockage, which would be odd at this point, or that tstat isnt fully opening..... I would install a mopar tstat before wasting anymore time. This is assuming the 'new' water pump is good.

Idk what year vehicle youre working on, but the pre-2007 is pretty much self bleeding with the hose running from the radiator to the coolant tank. Fill it up with the bleed s-crew removed till coolant comes out, then cap it and youre done. This doesnt apply to the 2007 KJ or the 4.7 WJ engine. Ive struggled to bleed a 4.7 in a WJ, even with the big funnel you can use to burp them.

Mine is an '07. I think it sounds like a capacity issue too But, I'm still leaning toward low coolant due to having air in the system rather than a faulty thermo'. I'm pretty sure I wasn't able to get as much coolant in as came out, but that's been hard to keep track of because I had to flush so much water through it.
But, if the fluid does have to come back out, I'll swap out the Gates thermo' for a OEM one.

 

[Duster]

Oh, you got an 07.

Air entrapment is a big issue. I have been there and it was bad. Do you have heat? I assume some yes since the time of year and you didn't say no heat. Mine was so bad I had no heat either. I had to get it on a very steep hill front up the hill, run it with heat on wide open the cap off until it spilled over, then put the cap on and crack open the bleeder shown above. After some curse words I got it out. I kept running back and forth checking for heat. I had air in the heater core and some air in the engine.

I personally think it helps a lot if when you refill to refill all you can through the bleeder ***** with a funnel. Then finish up the radiator. I didn't have near the issues last time and I think that is what I did.

You should also CONFIRM that your fan is cycling on when the temp starts to climb.

 

[Wesley]

I put a new radiator, water pump, thermostat and hoses on my Jeep earlier this week. I was not having cooling issues before the repair. I changed the parts because the radiator had a bad leak, and the water pump worked ok but was seeping a little around the seal.

I bought the car in November, and wasn't sure what type of coolant it had in it so, I decided to flush the radiator. Had a heck of a time getting all the old stuff out. I ran about 12 gallons of distilled water through it to get it to start coming out clear. And an equally difficult time getting the new anti-freeze in. I couldn't get the solution to the right mix because I couldn't cycle enough of the water out. Plus, it did fine just driving it around town but, when I took it up to highway speeds it started getting hot. After trying to get the air out of the system for two days using a no-spill funnel kit, I finally said uncle and took it to a shop to have them do a complete flush and refill.

Just picked it up about an hour ago, and still the same issue. Does fine around town when you're driving under 45 but, take it out on the road and it starts getting hot. I assume the shop wasn't successful in getting the air pocket out. In which case, I can probably just go back Monday and have them fix it. (I did tell them it only gets hot over 2,000RPMs but, I'm betting they just took it on a short drive in town) I know Libertys are known to have cooling issues so, I'm wondering if anyone has any other suggestions as to what could be going on? Do the sympoms I've described sound like air in the system or should I be looking elsewhere? As I said, no cooling issues before the parts changes, the job was done to stop leaks.

Thanks in advance for your tIME

I had a similar problem with my Jeep. After many tries I found out that one of the radiator hoses was collapsing at highway speeds. Around town it was never a problem. When I bought the new hoses I assumed (mistake) that there was a spring inside like the old hose. No such luck. I still had the old hose, removed the spring (it was in great shape) put it in the new hose and no more problem. Good luck

 

[LibertyTC]

Welcome Wesley,
I assume you are referring to the Mopar lower rad hose with the spring.
The spring does prevent the lower hose from collapsing, & I'll add the photo below with part number.
The mopar top rad hose does not need nor have a spring.

 

[Tech-Mechanic]

I had a similar problem with my Jeep. After many tries I found out that one of the radiator hoses was collapsing at highway speeds. Around town it was never a problem. When I bought the new hoses I assumed (mistake) that there was a spring inside like the old hose. No such luck. I still had the old hose, removed the spring (it was in great shape) put it in the new hose and no more problem. Good luck

I did replace the lower hose. The new one also did not contain the spring... I still have the old hose. I'll try putting the spring back in.

Would be great if it was that simple.

 

[JeepJeepster]

Twice..... Thats how many times Ive finished up replacing a radiator and looked over and saw that spring... Yes, I drained it and put it back in...

 

[Tech-Mechanic]

So, yesterday, we finally had a day here over 10°, and I got this dam thing figured out.

It had a loose nut behind the wrench... I put the thermostat in backward.

I'm not a smart man.

 

[JRB]

So, yesterday, we finally had a day here over 10°, and I got this dam thing figured out.

It had a loose nut behind the wrench... I put the thermostat in backward.

I'm not a smart man.

I love the saying- "Turns out I wasn't wrong, just mistaken!" for when these moments happen haha! Glad you found the culprit.