'00 XJ Overheating - Bad Water Pump - Page 2 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Cherokee & Comanche Forums > XJ Cherokee Technical Forum > '00 XJ Overheating - Bad Water Pump

TeraFlex Now at Rockridge 4WD! BEST DEALS around!Alloy usa heavy duty ball joint kitsENGO QUADLUX 6" to 54" LED AMBER AND WHITE MULTI

Reply
Unread 06-26-2012, 11:24 AM   #16
Kalali
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2012
Location: Ocean, NJ
Posts: 517
Quote:
Originally Posted by njsurfmaster View Post
So I drove it for about 30 minutes today in mostly highway traffic. Temp stayed right around the 210 mark, maybe just slightly higher. Decided to turn on the AC to make sure it wasn't going to cause any trouble. After 2 or 3 minutes at 55mph, I stopped at a light. Sitting at the light the temp gauge was at 210. While I was watching it, it immediately jumped into the red zone just before the 260 mark. This was not a gradual or even a quick rise in temperature. It was immediate.
Sean
A jump like that is obviously not physically possible. I do remember reading somewhere that in certain model years the sender is programmed to direct the gauge to jump from 220 right to the red zone in order to get the operator's attention. I don't know how true that is but sort of makes sense.
The best way to validate that hypothesis is using a temperature gun pointed right at the thermostat housing when it happens.

Kalali is offline   Reply With Quote Quick reply to this message
Unread 06-26-2012, 11:50 AM   #17
njsurfmaster
Registered User
2000 XJ Cherokee 
 
Join Date: Oct 2007
Location: Marlton, NJ
Posts: 88
Quote:
Originally Posted by Kalali View Post
A jump like that is obviously not physically possible. I do remember reading somewhere that in certain model years the sender is programmed to direct the gauge to jump from 220 right to the red zone in order to get the operator's attention. I don't know how true that is but sort of makes sense.
The best way to validate that hypothesis is using a temperature gun pointed right at the thermostat housing when it happens.
Makes sense. It jumps up and then the "check gauges" light comes on to get your attention. Agreed on the temperature gun.

Sean
njsurfmaster is offline   Reply With Quote Quick reply to this message
Unread 06-27-2012, 08:03 AM   #18
BillB7581
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2007
Location: New Jersey
Posts: 118
I just did my water pump this past weekend and the temp shot up on the initial test run... I thought it was full initially, but it "sucked in" another gallon a few ounces at a time once things cooled back down enough to take the cap off. I topped off the bottle for good measure and no problems since, it runs below 210 at all times on the guage with a missing fan shroud
BillB7581 is offline   Reply With Quote Quick reply to this message
Unread 06-27-2012, 09:07 AM   #19
CJ7-Tim
Real Jeeps have dents.
 
CJ7-Tim's Avatar
2000 XJ Cherokee 
 
Join Date: Apr 2002
Location: out in the garage - Minneapolis, Minnesota
Posts: 21,823
Quote:
Originally Posted by Kalali View Post
A jump like that is obviously not physically possible. ....
Yes, this is possible. The cooling system is pressurized to 16 lbs to raise the boiling point of the coolant. If the radiator cap becomes weak and unseals the cooling system, the superheated water can instantly flash to steam at any hot spot in the engine block. The steam will reach the water pump, interrupting the flow of coolant, creating more steam at the hot spots.

The ECU may buffer the display on the temp gauge, and the temps may or may not actually be 260*, but the cooling system is in fact overheated.

A new radiator cap is not expensive, I replace the thermostat and the radiator cap every other coolant flush, or about once every 4 years.
__________________
.

Between 2009 when Obama took office, and 2013, median annual household incomes have fallen by more than $2,100.

Progressive Liberalism: Bringing you new Healthcare ideas so wonderful, they have to include mandatory participation ......

Originally Posted by Ronald W. Reagan: Government is not the solution to our problems; Government is the problem.
CJ7-Tim is offline   Reply With Quote Quick reply to this message
Unread 06-27-2012, 09:14 AM   #20
BillB7581
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2007
Location: New Jersey
Posts: 118
And that little "compartment" in the thermostat housing,where the CTS sits is a perfect spot for the coolant to flash into steam (the highest point in the whole system) if you have air in your system. Mine was doing the same thing prior to changing the water pump.
BillB7581 is offline   Reply With Quote Quick reply to this message
Unread 06-27-2012, 09:20 AM   #21
SuperSam
Registered User
2000 XJ Cherokee 
 
Join Date: Jan 2012
Location: Northern, AZ
Posts: 144
fill the system properly as soon as possible. When water flashes to steam like that in an enclosed system it can tear up your internals, i.e. impeller.
SuperSam is offline   Reply With Quote Quick reply to this message
Unread 07-03-2012, 06:20 AM   #22
njsurfmaster
Registered User
2000 XJ Cherokee 
 
Join Date: Oct 2007
Location: Marlton, NJ
Posts: 88
Replaced the fan clutch and still have the issue, so that rules that out. It's really the only part that might not have been bad in the cooling system, but it was cheap enough to try.

I'm going to take it in and get it flushed since even after I flushed it, the coolant is still rusty. Hopefully it's trapped air that's causing the overheating. If not, I'm going to get an oil sample tested for coolant.

Sean
njsurfmaster is offline   Reply With Quote Quick reply to this message
Unread 07-03-2012, 08:19 AM   #23
BillB7581
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2007
Location: New Jersey
Posts: 118
Mine took another gallon after I thought it was full, a few ounces at a time
BillB7581 is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 11:03 AM   #24
njsurfmaster
Registered User
2000 XJ Cherokee 
 
Join Date: Oct 2007
Location: Marlton, NJ
Posts: 88
Update: I took the Jeep in today and had it flushed and filled. It still overheated. As a last resort, they recommended replacing the thermostat again just in case the one I put in a few weeks ago was bad. If that's not it, they thought it might be an issue with the head or head gasket.

So in summary...

Replaced heater core (to fix original no heat condition)
Replaced radiator (due to hole)
Replaced water pump (impeller destroyed)
Replaced all hoses
Replaced t-stat
Replaced radiator cap
Replaced fan clutch
"Professionally" flushed and filled

Other than the 0331 crack or maybe a head gasket issue, I'm not sure what else it might be.

Next step is to send in an oil sample for analysis.

Sean
njsurfmaster is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 11:51 AM   #25
n5xl
Registered User
 
Join Date: Oct 2005
Location: Arizona
Posts: 510
Just sitting back and watching all this roll by...I dont have anything to offer up that hasn't already been covered but I do have a comment. I dont think I've ever seen a water pump that bad before and I see you've had a plugged heater core (maybe it was leaking) and hole in radiator to go with it. What kind of antifreeze are you using and at what concentration? Short of running straight water as a coolant, I'm almost wondering if you dont have some sort of electrolysis going on to eat the pump up that way. Additionally, if the cooling system was in that bad of a shape, are the professional flush guys certain they got all the crap out? Maybe some internal passages are still blocked.

Were this my rig, I'd replace the head. Just knowing the history of what its been through coupled with the 0331 casting is enough of a doubt for me to replace it. As a bonus, youll get a head gasket job out of the deal too so you kill two birds.
__________________
Current Jeeps:
99 TJ, AX15, 2"BB,
99 XJ, AW4, 2"OME,
98 XJ, AW4, 2"ACOS/JKS Shackles
n5xl is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 12:20 PM   #26
BillB7581
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2007
Location: New Jersey
Posts: 118
Only thing I can think of is having a wrong rotation water pump. If your WP runs off of the backside of the belt like the 2000's do you need a reverse rotation pump. They look identical but the impeller faces the other way. Is your electric fan coming on?

I just replaced half of what you did in my 2000 and it runs slightly below 210 now even in this weather. I can see the thermostat open and close on the gauge, it creeps up toward 210 then when it opens it drops down slightly.
BillB7581 is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 01:06 PM   #27
BillB7581
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2007
Location: New Jersey
Posts: 118
See if the shop where you took it has one of those laser thermometers. Dont know the exact spec, but you should be getting 40-50 degree drop across the radiator, I would imagine.
BillB7581 is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 01:37 PM   #28
njsurfmaster
Registered User
2000 XJ Cherokee 
 
Join Date: Oct 2007
Location: Marlton, NJ
Posts: 88
Quote:
Originally Posted by BillB7581 View Post
Only thing I can think of is having a wrong rotation water pump. If your WP runs off of the backside of the belt like the 2000's do you need a reverse rotation pump. They look identical but the impeller faces the other way. Is your electric fan coming on?

I just replaced half of what you did in my 2000 and it runs slightly below 210 now even in this weather. I can see the thermostat open and close on the gauge, it creeps up toward 210 then when it opens it drops down slightly.
I replaced the water pump about 3 weeks ago. There was an 'R' stamped in the impeller to signify reverse rotation. The impeller blade direction look the same as what was left of the factory one I was replacing.

Sean
njsurfmaster is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 01:44 PM   #29
njsurfmaster
Registered User
2000 XJ Cherokee 
 
Join Date: Oct 2007
Location: Marlton, NJ
Posts: 88
I just went out (after it had cooled down from the drive home) and the overflow tank was empty. I filled it to about 1/2 way between add and full and ran it for a while. It sucked in everything from the bottle, so I filled it again about 1/2 way between add and full. This time it stayed pretty close to that level.

I ran it for about 45 minutes (idle and a few short trips around the block) before it overheated again. The overflow filled almost to the top of the bottle before it stopped.

One thing that I noticed this time that I have never seen before is the oil pressure was way down after sitting at idle for the last 10 minutes. When I kicked up the RPM's the oil pressure went back up and it overheated right after that.

Is low oil pressure an indicator of the head issue?

Outside temp is 96deg right now.

Sean
njsurfmaster is offline   Reply With Quote Quick reply to this message
Unread 07-05-2012, 04:10 PM   #30
Kalali
Registered User
2000 XJ Cherokee 
 
Join Date: Apr 2012
Location: Ocean, NJ
Posts: 517
Quote:
Originally Posted by njsurfmaster View Post
I just went out (after it had cooled down from the drive home) and the overflow tank was empty. I filled it to about 1/2 way between add and full and ran it for a while. It sucked in everything from the bottle.

Is low oil pressure an indicator of the head issue?

Sean
If there is no external evidence of coolant leak, then I'm willing to bet that missing coolant went right into your oil sump. Check your oil level and you'll find an extra quart or more overfill. Your "head" is talking to you and telling you replace me before I destroy the rest of the engine....
Kalali is offline   Reply With Quote Quick reply to this message
Reply

Tags
overheating

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.