TFitzPat87

Hey All,

Paranoid Tom back with another question for you guys. I wonder if I can change my username to that. LOL!

Anyway... I know my thermostat is working (opening) as my XJ isn't overheating cause its stuck closed, but it doesn't seem to pop open until after 210*. If I had to guess it maybe opening at like 215ish (maybe a little higher). Is this normal, or is this reason for concern? Once opened it cools back down to 210, and stays there + or - a degree or two. It only warms up past 210 if I'm not moving for a bit, but then cools back down to 210 when I'm moving again.

As always, thanks for the imput!

Crazy 8s

Buy a new one and replace it. Flush your coolant while you are there because summer is coming up. It sucks to overheat in traffic in the middle of summer.

FruitSnacks

Yes, pick up a 195° tstat and give 'er a good flush

TFitzPat87

Thanks guys. I was thinkin the same thing. Is this reason for concerns though?

I do seem to be very slowly loosing coolant, but I have no milky oil, and no white smoke out of the exhaust, and again, most importantly, I'm not over heating. The only time it warms up above 210 is before the tstat opens up, and if I'm stuck in traffic, it creeps up until the fan kicks on.

Speaking of which, does that mean I have an electrical fan, or do all XJ's have a fan clutch? Still learning here, so thanks for the help!

98XJSPORTSATINJADED

Mine stays at 200 constant the original t stat is 192° that's what I replaced mine with.

md21722

Your 1997 Cherokee has two fans: a mechanical fan with a fan clutch and an electric fan. The electric fan should cycle in response to the coolant temperature.

If your temperatures are creeping up at idle or low speed, your fan clutch may old and weak. Replace the fan clutch. The ones from NAPA cost about $35. Make sure you put the fan back on the way it came off. They will bolt up to the clutch backwards and forwards. Also make sure your condenser and radiator are not filled with sand, dirt, and bugs. That can really restrict airflow.

If you are losing coolant you should find out from where. You could have a leaky hose, leaky radiator, leaky water pump, leaky thermostat gasket or water pump gasket, leaky freeze plugs, slightly blown head gasket, or cracked head. Try to find an external leak. Make sure the hose clamps are tight. It takes significant coolant in the oil for it to look like a milkshake.

The head is off my 1997 right now because it was losing small amounts of coolant. I know there was coolant in the oil because I had it tested. It too seemed to run a little warmer than my 2001.

TFitzPat87

Thanks MD.

What made you decide to get your oil tested? Were you having any symptoms that made you think it was necessary?

I think I have a small leak on a smaller diameter hose. It's near the left side of the rad (if your sitting in the drivers seat) at the bottom. It's always wet around there, but I never get any puddles under the Jeep. Maybe it's more pronounced when I'm moving...Like I said, it's very little at a time and takes a bit before I can even tell the levels dropped. I'll try and get a picture of where I think it could be leaking from.

I'm not overheating, no white smoke out the exhaust, no milky oil, coolant is green. It might not be perfect coolant but at least it's green. I've actually been driving my jeep like this since I bought it, almost a year ago now. Nothing has gotten any worse. I feel like if I had a cracked head or slightly blown head gasket it would have gotten worse over time. What's the test to see if it is a blown head gasket or cracked head? I've looked under the valve cover, and see oil pumping and nothing else. I only thought to ask because I found it kinda weird that my tstat doesn't open till about 215ish and then cools right back down and stays at 210 unless I'm not moving or in stop and go traffic then it starts creepin.

I guess I'll go ahead and replace my fan clutch, as I have no idea if it's ever been replaced. I'll also get the coolant flushed and drop in a new tstat.

Also, so you all know. 97' Sport, AW4, NP231, 72k miles.

s346k

I think your jeeps operation sounds normal. if you've never flushed the coolant and replaced the tstat I would do that anyway. to check the clutch fan...it should spin freely when cold (check it before you leave in the morning after it has sat overnight; ENGINE OFF)

and check it hot, after the engine has reached 210 or above and been there a few minutes. ENGINE OFF. it should be difficult to spin.

Fred/N0AZZ

^^What he said^^

Firestorm500

Normal operation.

Keep calm and carry on.

md21722

My 2001 XJ rarely goes a needle width past 210.

My 1997 XJ creeps up under load to one full tick past 210.

Cooling systems are in the same condition (everything replaced less than 1 year with the same parts). The only difference between the 1997 and 2001 is that the 1997 also has an older evaporator and transmission cooler in front of the radiator.

I have been testing oil for many years. The loss of coolant and higher than expected engine temperature led me to believe it was ending up in the oil pan. Results showed traces of coolant in the oil.

bigbadon

Are you sure it is actually 215 degrees?

TFitzPat87

Am I sure it's 215 when the tstat opens? I don't know the exact number, that's just an estimate. That is the only time it ever gets above 210, unless I'm stuck in traffic or not moving for a while then it starts creeping up until the efan kicks on or until I'm moving again then it cools back down to 210.

If I'm moving, the needle never passes the 210 mark. Maybe the slightest bit higher or lower, but it's ALWAYS on the 210 mark on the gauge.

Edit: from MD's last post, mine does exactly what your 2001 does. The needle never moves off the 210 mark, except on my initial warm up until the tstat opens.

I wonder if my tstat is just a little old and opening slow, thats why it gets a couple degrees warmer before it opens up enough. Just a thought.

bigbadon

Don't trust a $2 OEM dash gauge

SeaVee

Well, my 02 does the same thing, fan never stays on for more than a minute or so once it kicks in. I've flushed, and check oil and coolant, all good. Gonna do an oil analysis soon, got to change my OFA. Was gonna post to poll the experts but you beat me to it.