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I'm stuck!! Is there more than one kind of waterpump for the 4.0?

01_XJ

NAXJA Forum User
Location
Emporia, KS
After having overheating issues all this week, and having a leaky radiator and bad thermostat fixed, my water pump went out today. I went to Kragen and bought a new water pump, hoses, thermostat, rad cap, and temp sensor to hopefully get rid of any cooling issues. Well when I finally got the old pump off, and the area cleaned up to put the new one on, it wouldn't fit. It seems that the impeller sticks out on the back side of the pump too far and it rubs on the outside wall of that first cylinder. the bolt pattern is a perfect match for the one I removed, though. I finally gave up on if about a half hour ago, and will go at it tomorrow again. So can anyone tell me if I might have the wrong pump, or is it something I'm doing incorrectly?

Also, this is on a 2001 XJ w/ the stock 4.0.
 
There are numerous pumps for the 4.0/242 C.I.--you probably got one that was shipped in the wrong box.

Please don't tell me it is a reman? Only NEW for water pumps.

You should be able to measure the old and new pumps, take them both in when you return the pump you have.
 
It was a new pump. I guess I'll take it in tomorrow to see what other ones they have. One thing though, my XJ is a 2001 but when I had the radiator replaces last year the guy said that when he tried to put the correct rad for the 2001 in, it didn't fit and that the part for the 2000 did fit. I wonder if this might have something to do with getting the wrong part on the water pump.
 
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Usually when I look up waterpumps for the 4.0 it asks for the hub height/diameter, and there are two different ones:

Water Pump - New
Product Line: Tru-Flow Water Pumps
Comments: w/ 2.31" Hub Height & 3.30" O.D. Hub
Per Car Qty.: 1
Part number: TFW 42004

Water Pump - New
Product Line: Tru-Flow Water Pumps
Comments: w/ 3.72" Hub Height & 2.65" O. D. Hub
Per Car Qty.: 1
Part number: TFW 42002

BUT for your 2001 (and my 95 I just checked as well) it only lists the 42004. :dunno: take your old pump with you and ask if they can interchange the other number I gave you (42002), if it comes up that they have that one in stock check that one against your old one as well.

here are pics of both hubs:

42004
670065.jpg


42002
592738.jpg


hope this helps you out some. Those are NAPA part numbers btw. good luck. As far as I know those are the only two waterpumps in the catalog system for the XJ w/4.0
 
Yea, I think that the last time I changed the water pump on my x-gf's XJ, I used one from Napa, so I will probably head over there tomorrow. It seems like I never have a problem with Napa's parts, but I do occasionally with Kragen and Autozone.
 
for what its worth i just had an idea and looked up the pump for a grand cherokee, and in the "what else it fits" section i noticed the XJ 4.0 was not listed.

this is the GC pump:
592933.jpg


670246.jpg


and it only fits a grand or a wrangler, the 42004 I posted above only fits XJ/MJ models starting at 87 and going up to 2001 (honestly I dont think I've ever seen one take the 42002). If they sold you the one for a grand then you got the wrong pump. you can most likely double check the part number you got on their website by looking up your vehicle and seeing if the number matches.
 
The 42004 looks identical to the one I pulled off, and looks like it is the same as the new one. I just went and compared the pulleys and they are identical. At this point I'm wondering if I'm just doing it wrong.
 
do they look identical in size etc when sitting side by side? if so then yes you are doing it wrong, lol :D if one sticks out further in back than the other you got either a misbox, or a defective pump. Thats the best I can do for you from 2 hours away via the interweb ;)
 
I'm gonna try one more time tomorrow. I started late this evening and was already really frustrated after having my heap overheat everyday for the last week, so I don't doubt that my lack of patience was contributing to the problem. I can't remember, do I need to remove the ps pump, or at least that part of the bracket that sits in front of the water pump a bit?
 
i did my pump about a month a go. i too thought it was too deep, turns out the hard line for the heater core was in the way. and i didnt remove anything else, except the hoses, the pump came off nicely.
 
... I can't remember, do I need to remove the ps pump, or at least that part of the bracket that sits in front of the water pump a bit?

You don't need to remove the P/S pump but you do need to take out the one bolt that the pump shares with the P/S bracket and slide the pump in/out to the left.

...and at the parts store make sure that there is an "R" stamped on the inside (usually on the impeller) to indicate reverse rotation and be sure the belt is routed correctly when you put it all back together.
 
The good news:
I tired it again this morning and everything fit fine. I ended up loosening up the p/s pump and the water pump went right in. I also replaced all the rad and heater hoses, t-stat, temp sensor, and rad cap.

The bad news:
I went to turn the thing on, and as soon as I turned the key over, it all died. I must have got water on something and blew a fuse. Soooo, where do I start now? Main fuse?
 
Describe, in detail, "it all died".

Will it crank the engine?
 
I turned the key to where the gauges and a/c will come on, and it did, but when I turned it over to start the engine there was a click and then nothing. Now when I insert the key, not even the gauges will come on.
 
I just checked the fuses in the cabin and all are intact. I also checked the colored fuses under the hod and all of those are also intact.
 
What is the voltage at the battery terminals?
Are the terminals clean and clamps tight?
Check the positive terminal at the starter to ensure it's clean and tight...
Disconnect the fusible link at the PDC and measure continuity from the terminal end to the alternator to ensure the fusible link isn't blown.
 
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