HOW TO: Flush/Change Coolant

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metalmoto

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Jeep would only take 3/4 of a gallon on coolant

My plastic reservoir tank was cracked, right where the small hose goes to the radiator, next to the upper radiator hose. So I got a new tank. I wanted to do a complete flush and fill, and also replace the thermostat. First off, I could not get the bleed screw out to save my life. I tried WD-40 and even heating it with a propane torch. So I gave up on that... Then I went to remove the belt tensioner, to access the thermostat, but the nut was stripped. So I couldn't do that either! So I drained it using the radiator petcock, and used a garden hose in the the radiator, where the upper hose connects. And also ran water through the lower hose on the reservoir tank, and drained it all again. Then I put on the new reservoir tank, connected all the hoses, and filled it with 100% hoat coolant. It would only take about 3/4 of a gallon to reach the full cold mark.
I ran it to normal temperature, the heat was working fine, and I even drove it a few miles. But the level never went down. I'm just afraid I don't have enough coolant in there to prevent it from freezing, when the winter comes!
I have a 12 mile drive to work tomorrow, and hoping it doesn't overheat on the way. I have a Gallon and a quarter of coolant in the back of the jeep and a gallon of distilled water, just in case it gets too hot... My temperature gauge always goes to the middle, and never higher. And the fans never seem to come on, unless I use the A/C. Can anyone help me? I will take any advice to help me keep my Jeep going. Thanks
 

HoosierJeeper

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Have you run it with the cap off? I'd do that for 5-10 mins, shut it down and see if it dropped at all, add more, repeat till it holds steady.
 

metalmoto

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Yes, I ran it for a while with the cap off. but the level never dropped. Then I replaced the cap and took it for a drive for a few miles. It didn't overheat. But the level hasn't gone down yet. My thought is that there was still a lot of water in the engine. If the level doesn't go down, perhaps I will try draining the radiator again, after a long drive. I'm just trying to get the mixture right, so it wont freeze in the coming winter. I will keep you informed. And Thank You!
 

profdlp

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Siphon the reservoir dry and fill it with 100% HOAT. Enough cycles like that and you might be able to balance things out.

If/when you re-do it, try removing the lower radiator hose and drain it there. Combined with the petcock you ought to get it drained pretty well. Of course, the best thing would be to take care of that stripped bolt. Sooner or later that belt is going to go (ask me how I know...) and you won't want to have two problems on your hands. :)
 

metalmoto

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That was exactly what I was thinking. So far, I put a gallon of HOAT into the reservoir tank. And the level is just a little over half, in the the tank. It's not overheating. I figure that I'll buy a new belt tensioner, just in case I have to cut or drill the old one out. Then I'll drain the radiator again, replace the thermostat, replace the tensioner, and add more full strength HOAT to the Reservoir tank. Then check it with a coolant tester. Hopefully this will be good enough to protect it from freezing in the winter. Thanks again!
 

stn

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Still not convinced

I replaced my coolant, T Stat, and water pump the other day, and I've not seen any issues yet. I drained from the radiator drain and replaced as the service manual indicated.. I think the whole thing ran me about $140 in parts including an easy out set for the damaged TStat housing bolt.

However I'm still not convinced that the coolant bleeder is an 8mm HEX...It seems MUCH more like a Torx head to me.

gp
 

profdlp

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...I'm still not convinced that the coolant bleeder is an 8mm HEX...It seems MUCH more like a Torx head to me...
Have you got a fine point pick or scribing tool? Make sure the thing is really cleaned out and crud-free, because:

definitely not a torx. definitely a hex unless you have a non-mopar replacement on yours.
...and it certainly is possible someone swapped it out at some point, unless you bought it new and are sure that a mechanic didn't lose the original and just drop something he had handy in there to get you out the door.
 

LeilaMisConcepcion

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hoses for dummies HELP!!!!

Ok so really stupid question. Where EXACTLY can I find the upper and lower hoses? I'm a newbie to taking care of my 2002 and it really needs a flush. I know how to get it done, but the owners manual has no diagrams that show the location of those hoses. Any hel
p would be much appreciated!
 

uss2defiant

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Ok so really stupid question. Where EXACTLY can I find the upper and lower hoses? I'm a newbie to taking care of my 2002 and it really needs a flush. I know how to get it done, but the owners manual has no diagrams that show the location of those hoses. Any hel
p would be much appreciated!

look for the radiator, what ever hose that is connected to the top of it is the upper radiator hose and likewise if a hose is connected to the bottom it is the lower radiator hose.

For Left hand side Libertys, the upper radiator hose is on the driver side.

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You can see in the picture the overflow line is right on the upper radiator hose, just to the left of the fuse box and battery.
 

05BlueLiberty

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Hey guys, new to the site. I've posted an Introduction in the "introduce yourself" section of this forum. Well my issue is, the Liberty's coolant bleeder is stuck and I am hoping you can straiten out some conflicting info I have read on this and other websites.

To start, I have an 05 Liberty sport 2WD with the 3.7l.

Some videos and threads have stated you need to use the bleeder to remove the trapped air in the cooling system after replacing the coolant/water pump/T-stat etc. but in the original post of this thread it states "NOTE: The engine cooling system will push any remaining air into the coolant bottle within about an hour of normal driving. As a result, a drop in coolant level in the pressure bottle may occur."

So can anyone shine some light on this? Do I need to use the bleeder or not? My bleeder is extremely suck and I do not want to risk damaging the front water pump housing requiring me to replace it.

Any clarification would be great, thanks everyone.
 

profdlp

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The bleeder might speed the process up, but in a case like yours where you're afraid of causing more damage trying to get a stuck one loose I would rely on patience as a sound alternative.

In other words, don't worry about it. (Provided engine temps stay in the normal range. A little gurgling for a few days never killed anyone.)
 

05BlueLiberty

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So it is not necessary to use the bleeder, it is just there to expedite the process of removing air from the cooling system. Got it, thanks for the quick reply profdlp!
 

profdlp

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Just be sure and keep an eye on the temp gauge. These engines do not like to be overheated, not even once.

And you are using HOAT, right? If not, buy a spare water pump while you're at it. ;)
 

05BlueLiberty

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Yep, well aware of the HOAT requirement. Luckily I thoroughly research before working on my cars. Going to be picking up 2gal of MOPAR concentrated HOAT and a T-stat to do the flush. Just replaced my cooling fan due to the low speed going out on me, wife was in a drive through when she noticed it getting hot. She shut the engine down as soon as she saw it. I don't believe it actually overheated because it shows no signs of damage, no CEL codes, and still runs strong.

I figured if the fan died then it was time to start some cooling system maintenance. Especially before this central California summer hits.
 

profdlp

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I plan to do mine soon, as well. Good luck to you! :waytogo:
 

Myke

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What is the high limit for safe Temps on the 3.7?

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K9JEEP

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Hey guys, new to the site. I've posted an Introduction in the "introduce yourself" section of this forum. Well my issue is, the Liberty's coolant bleeder is stuck and I am hoping you can straiten out some conflicting info I have read on this and other websites.

To start, I have an 05 Liberty sport 2WD with the 3.7l.

Some videos and threads have stated you need to use the bleeder to remove the trapped air in the cooling system after replacing the coolant/water pump/T-stat etc. but in the original post of this thread it states "NOTE: The engine cooling system will push any remaining air into the coolant bottle within about an hour of normal driving. As a result, a drop in coolant level in the pressure bottle may occur."

So can anyone shine some light on this? Do I need to use the bleeder or not? My bleeder is extremely suck and I do not want to risk damaging the front water pump housing requiring me to replace it.

Any clarification would be great, thanks everyone.
I had the same thought about the California heat when I picked up my 07 a few months ago so I took it to the dealer and had them do a coolant and transmission flush to prepare for summer so if it were to have any issues I could take it back to them. So far it has been running fine. It wasn't overheating before but I didn't know when the last time the coolant was flushed so I would rather be safe and have everything fresh

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