[Badsneakers]

Hi Huys/gals,

Newbie here. We have a 2000 Cherokee LTD with about 190k on it. The radiator blew a month ago and I replaced it along with the drive belt. All was fine. 2 days ago it started overheating. It warms up normally to 210. It creeps to 220 in about 5 minutes. Fan comes on normal. After about 10 minutes at 220 it shoots all way up to the red. I swapped the Tstat no luck. Still doing the same thing. Heater blows cold also. Top hose is hot, bottom cold. Rad is about 175 degrees, top hose about 220.

Any suggestions?

Thanks!

[Greenz]

Plugged heater core sounds like.

Remove your heater hoses at the thermostat housing and try back flushing with a garden hose.

[Badsneaker]

Hmmm, would a plugged heater core cause the overheating too?

[highwayman]

Sounds like a air pocket. A plugged HC will not cause your rig to OH. The best trick I did when flushing the 4.0l was too pull the gauge temp sender at the rear of the cyl head on the dr side while filling. Dont keep running it hot those heads/gaskets don't like overheating. Hope this helps.

[Badsneaker]

Well no air pocket.

Water pump is shot. The impeller looks like a Chinese throwing star! That that can't be moving the coolant too wel now can it!?

It got dark so I had to wrap it up for tonite. I'll get it swapped tomorrow and let you know the results.

I'll probably need a new heater hose connector too. The old one is rusty and will probably break if I can even get it off the old pump. Also I may have warped the pulley prying it off the pump. It was stuck pretty good. I'll pick these up at the dealer tomorrow. hopefully they have them in stock.

[KevinKrupp]

get a new thermastat. and get a new 185 degree...

also at autozone get this stuff called water wetter.

drain the radiator, and put i whole bottle in....

also does it have an electrical fan?

if so you might have to over ride it. by running it to a switch or a new temp. control. which can tell it when to turn on.


also take a hose and spray out the radiator fins and make sure there is no mud in them

[AZ Jeff]

Originally Posted by KevinKrupp

get a new thermastat. and get a new 185 degree...

I think you mean a 195 degree, NOT a 185. (BTW, I am not sure a 185 exists. A 180 does, but not a 185.)

Originally Posted by KevinKrupp

also does it have an electrical fan?

if so you might have to over ride it. by running it to a switch or a new temp. control. which can tell it when to turn on.

A properly operating XJ cooling system does NOT "need" an override on the electric fan to make it run at it's proper operating temperature of 210 degrees F.

As far as the original poster's problem, if the top hose is hot, and the bottom is cold, I suspect no circulation of water. If the T-stat is new, I have to ask--was it installed the correct direction (spring towards the HEAD)? Also, was the radiator that was replaced NEW, or used? Has it's flow rate been checked by a rad. shop?

[sprintagogo]

Originally Posted by KevinKrupp

also at autozone get this stuff called water wetter.
drain the radiator, and put i whole bottle in....

Don't waste your money onthis stuff. I have tried it on a performance chipped motor that was just a bit to hot for the stock cooling system when on full blast. It made absolutley no difference whatsoever. If your cooling system is up to scratch it will be perfectly adequate in stock condition.

[Badsneaker]

I put a new radiator, Tstat (195) hoses, and serp belt on it. The electric fan works fine. The impeller on the water pump has eroded into what looks like a saw blade.

[mhall02]

Originally Posted by Badsneaker

Well no air pocket.

Water pump is shot. The impeller looks like a Chinese throwing star! That that can't be moving the coolant too wel now can it!?

Wow, sounds pretty worn, how many miles did you get out of it? I've put as many as 150,000 miles on a water pump and the impeller didn't look too bad. I've always had them start leaking out the weep hole as a sign of the time to replace (w/ the exception of the one with 150,000 on it, I thought it was just due after that many miles). My 2000 has 135,000 on it w/ the original pump, but so far no leaks and it runs as cool as it did new.

[Jeepmaster12]

Got a 2000 jeep cherokee sport 4.0L.. When mine OH the motor shakes.. Idk what it is HELP Please

[dcorn]

Originally Posted by Badsneaker

I put a new radiator, Tstat (195) hoses, and serp belt on it. The electric fan works fine. The impeller on the water pump has eroded into what looks like a saw blade.

Makes you wonder where all that excess metal went, eh?

[AZ Jeff]

Originally Posted by Jeepmaster12

Got a 2000 jeep cherokee sport 4.0L.. When mine OH the motor shakes.. Idk what it is HELP Please

Your message has a bit too much shorthand. Are you saying your engine overheated, and now it's shaking when running?

If so, let's ask some background:
1. how MUCH did it overheat? Where did the temp. guage wind up, and for how long? Did steam come out from under the hood?
2. since it overheated, what did you do to repair it?

Answer those questions, and we might be able to help you.

[heepsterxj]

to the OP, just make sure you have a good tstat. I ended up with two faulty ones before getting one that wouldn't get stuck. Was causing no heat in the cab, and engine was overheating.

ended up replacing water pump and tstat and rad cap, all is well in the world....at least for now.

[Millermagic]

Originally Posted by heepsterxj

to the OP, just make sure you have a good tstat. I ended up with two faulty ones before getting one that wouldn't get stuck. Was causing no heat in the cab, and engine was overheating.

ended up replacing water pump and tstat and rad cap, all is well in the world....at least for now.

Had that happen on my Taurus. Problem was, where the temp sensor was, it was showing that it was running cool.