Normal operating temp, summer + highway? - Page 2

**Jerry Bransford** · 07-09-2010, 09:32 AM

If you mix your own coolant, be sure to only use distilled water and not tap water. Tap water has disolved mineral content which will build up inside the radiator and lead it on a slow path to getting clogged. Distilled water is sold by the gallon in any grocery store in the water aisle.

**Unlimited04** · 07-09-2010, 09:49 AM

Quote:

Originally Posted by BChamberlin

Can someone tell me what the point is of buying the coolant you mix vs. the stuff that already comes mixed and ready to use? I guess I'll go ahead and flush the radiator this weekend. Do I have to use the cleaner that Prestone sells? Seems like a PITA. You have to add it, drive 300 miles, drain it... fill, drain again... fill.... blah!

well i don't believe any company sells a HOAT pre-mix...soo....

remember with the Prestone flush kit, you'll still have a gallon or so tap water left in the block after you drain it...so you can either drain the block (screw fitting under the exhaust manifold), or just ignore it. make sure to buy a anti-freeze tester and distilled water. A little tap water from the hose won't hurt anything as long as everything else you mix is with distilled. then use the tester to make sure you get a good mix, after the radiator is filled....remember you'll have pure water left over throwing off your mix.

DevilDogDoc · 07-09-2010, 09:54 AM

I don't believe his 99 needs HOAT should use the green stuff like my 97 not that it would hurt anything either way...

**Unlimited04** · 07-09-2010, 10:05 AM

Quote:

Originally Posted by DevilDogDoc

I don't believe his 99 needs HOAT should use the green stuff like my 97 not that it would hurt anything either way...

doesn't NEED it by factory spec...but wouldn't hurt anything...won't need changed for another 100k

DevilDogDoc · 07-09-2010, 10:13 AM

Well as I said before it won't hurt but all the manuals I have read state the 100000 change is for the factory fill then it goes to 60000 for coolant changes. Myself it's cheap insurance and I do it every 2 years or so. Overkill? Maybe but my rig never hits hotter than 200 in the blazing desert heat...

skinton · 07-09-2010, 10:23 AM

Don't know about the premix being cheaper. I picked some up at Wal-Mart the other night. 1 gallon of premix was about $1.00 cheaper than 1 gallon of full strength. I think the premix was $9.50. So the cost of 2 gallons the premix route would be about $19.00. Two gallons by mixing yourself would be about $12.50 (assuming distilled water is maybe $2/gallon).

I bought the premix, because I was going to top off the reservoir in the Wal-Mart parking lot and it was just easier that way. I was lazy at midnight when I had to get up for work in a few hours. (doing some late night maintenance on the wife's Jetta)

**Jerry Bransford** · 07-09-2010, 10:25 AM

Quote:

Originally Posted by skinton

Two gallons by mixing yourself would be about $12.50 (assuming distilled water is maybe $2/gallon).

I don't pay much attention when I buy it but I believe a gallon of distilled water is well under a dollar.

**BChamberlin** · 07-09-2010, 10:25 AM

Now the thread went to talks about HOAT. LOL! I didn't even know what that was... and why I should get it. The more I learn on here, the more I don't know!

**Unlimited04** · 07-09-2010, 10:37 AM

Quote:

Originally Posted by BChamberlin

Now the thread went to talks about HOAT. LOL! I didn't even know what that was... and why I should get it. The more I learn on here, the more I don't know!

old school green coolant is IAT (inorganic)
HOAT is new stuff, not green. HOAT = Hybrid Organic

the two do NOT mix...you'll destroy stuff.

HOAT has new anti-corrosion chemistry that lasts far longer than IAT. most people don't realize they need to change IAT every year or so, the anti-corrosion stuff in IAT doesn't last long. people don't change it, the entire coolant pH changes, the system starts rusting/corroding, the radiator & heater core corrodes and starts leaking, then the system clogs and the engine start overheating. by that time the damage is already done and you gotta replace expensive parts. so manufacturers like Ford, Benz and Jeep went to HOAT so it would last longer with less maintenance....meaning less anti-freeze waste poured down drains and into drinking water systems...etc.

**aaonms** · 07-09-2010, 10:49 AM

Quote:

Originally Posted by BChamberlin

The more I learn on here, the more I don't know!

I wholeheartedly agree…

Has your Jeep seen much mud?
If so, might want to consider running water through the radiator (externally) from rear to front.

As to the original question: a bit over 210° is about what I see here in Florida heat.
Periodically renewing the coolant is a good thing.
I do as the others mentioned and use distilled water.
Renewing the radiator cap is good.

Wondering in what condition the thermostat is.
My OEM unit failed a few years back and I was fortunate that it was most of the way open when it did.
My water pump developed a small leak last month so I renewed the four hoses and the thermostat at the same time – cheap insurance. Renewed the coolant too.

Good luck.

**BChamberlin** · 07-12-2010, 12:09 PM

Okay, so the new rad cap definately didn't take care of my problem. This is what I know for sure. Anything under 50MPH and below, normal temp for me is about 210. Doesn't go higher and doesn't stay lower. If I'm going about 60MPH, it jumps to 220 or so but stays there. Today I pushed it up to 70 on the highway and I red lines and the check gauge light came on. It's got plenty of coolant from the last time I added it last week. I'm not missing, sputtering, and I have no signs of white foam under the oil cap. I'm not even shooting anything out of my exhaust. Could it be a bad stat? I haven't flushed the radiator yet but don't see how that could be an issue.

joeskyline06 · 07-12-2010, 12:28 PM

mine runs a little hot too, i have been thinking about buying a 180 degree thremostat, anyone run one? does it keep the engine at 180 constatly or does it just open at 180?

DevilDogDoc · 07-12-2010, 12:42 PM

If your running hot a different thermo won't change that at all you need to find what's causing you to run hotter than normal, correct that then the thermo will keep you running cooler

**BChamberlin** · 07-12-2010, 12:48 PM

Well I can't figure it out. How do I know if I have a leak in my head gasket before tearing the engine apart? I don't want to have to do that work for nothing. What about a water pump? Could that be the cause of anything?