How-to replace the water pump on a Jeep Wrangler TJ

Tim Redman

TJ Enthusiast
Joined
May 25, 2018
Messages
167
Location
Tampa Bay, FL
Tips from an amateur mechanic and first time Jeep owner.

I had my water pump go on me Saturday afternoon (coincidentally, on the way to a Jeep event, but thankfully, not on the trail). I've done water pumps in other cars before, so fortunately, I didn't go into this blind. For step by step instructions, I more or less followed
from Youtuber ChrisFix. But even so, here are my observations on the process.
  1. Hydrate
  2. Fan & Fan Clutch Removal: remove serpentine belt first, remove upper radiator hose, use an 18" pipe wrench on the fan bolt, and a strap wrench on the water pump pulley, strike pipe wrench with hammer (regular carpenter's hammer, not BFH) to knock loose, have patience & be persistent, don't try to muscle strap wrench and pipe wrench together unless the strap wrench is heavy duty, or else you may pull out the rubber strap. Wait until nut is loose before removing fan shroud, undo fan nut last and remove as a group. Expect to lose at least some skin during the process. Celebrate all the new space you have to work in, it'll be your last celebration for a short while.
  3. Hydrate
  4. Pliers, Channel Locks, Vice Grips Or Witchcraft: When it comes to hose clamps, especially the larger diameter ones, use the right tool for the right job; the wrong tool takes entirely too long
  5. Hydrate
  6. Make A Hole: Don't forget to remove the top idler pulley, in order to free up the metal pipe on the water pump
  7. Hydrate
  8. Leverage: Be sure to remove hoses while parts are still securely fastened to the engine; you'll get much better leverage on them, and the same goes for putting them back on.
  9. Did I Mention Hydrate? It's summer, and I'm in Florida.
  10. Appreciate The Little Things: When it comes time to remove the water pump and thermostat housing (you are replacing the stat also, aren't you? You really should), enjoy the relative ease in which most of the bolts come off. You will never get this opportunity again.
  11. Working In The Rain Does Not Count As Hydrating: Though as long as the thunder stays on its side of the playground, it can be refreshing (once again, Florida)
  12. Gasket Mating Surfaces: It doesn't matter how long every other task takes, when you're ready to clean the gasket residue off the mating surfaces, TAKE YOUR BLOODY TIME!!! Everything else can look like a pathetic train wreck; in contrast, this needs to be perfect. Not following this rule means you'll be doing most of these steps again pretty soon.
  13. Workspace Maintenance: Keeping the kiddie pool between the car and the front door of the house can make an effective detour between tasks.
  14. Sealants: Any bolts or other fixtures that act as a water-tight pressure seal will need teflon thread sealant; you can either use the liquid stuff, but I've found that teflon plumbing tape works as well, and makes less of a mess.
  15. Time Management: Don't look at your watch; far more time has passed than you had originally planned for, and you really don't want to know specific details on how much.
  16. Torque Settings: learn them, love them, obey them, or else you do something random like, oh, I don't know, snap the thermostat housing in half and have to fork out $12 at the auto parts store for an emergency replacement (hypothetically, of course). See below for details.
  17. While You're At It: Wouldn't be a bad time to change your serpentine belt, either.
  18. Wrapping Up: By this time, you should be thinking less about a shower and more about somebody just hosing you down in the yard.

Torque Settings:
Thermostat housing bolts: 2004 2.4L - 28 N-m / 250 in lbs
1997-2002 2.5L - 18 N-m / 13 ft lbs
1997-2006 4.0L - 18 N-m / 13 ft lbs
1997-2006 any others - 20 N-m / 15 ft lbs
Water pump bolts: 2004 4.0L - 23 N-m / 200 in lbs
2004 2.4L - 12 N-m / 105 in lbs
1997-2002 2.5L - 31 N-m / 270 in lbs
1997-2006 4.0L - 31 N-m / 270 in lbs
any other 2.5L & 4.0L - 30 N-m / 22 ft lbs
 
Great write-up, and not too shabby for an amateur mechanic. I'm assuming you got it all back together and it doesn't leak or anything?

It must be hot as hell out there too! It's 95 here, but the humidity there in Florida will make you pour sweat!
 
Great write-up, and not too shabby for an amateur mechanic. I'm assuming you got it all back together and it doesn't leak or anything?

It must be hot as hell out there too! It's 95 here, but the humidity there in Florida will make you pour sweat!
Most of my backyard auto projects usually end with a laundry list of things that "you just don't do the way I did them", but like I've always said, I've never learned anything worth learning by doing it right the first time. To me, it's just as important to learn "why" you're doing something, instead of just how to do it. And if I don't trash the car in the end, well, bonus.

But after all is said and done, new water pump, new thermostat, no leaks, and OBDII has it never going over 203 since Sunday (usually sitting between 197 and 203 after it warms up). And, of course, I probably transgressed every conventional wisdom and advice to not go with a Mopar water pump, doing a mid-grade generic auto parts store one instead. But my girl is a daily driver who had to be up and running by 8am Monday morning, and it's not an easy task to find a Mopar water pump on a Sunday within walking distance (or within just about any distance on a Sunday). So I may have to do it all over again in a couple of years, but at least next time, I'll have a better idea of what I'm doing.

You always hear people down here say, "it's not the heat, it's the humidity". No, it's the heat. AND the humidity. I'm sure biologists here have names for all of the different ways you can sweat in Florida.
 
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I've been to Florida several times, and the one thing I remember is getting off the plane in Miami and being like, "WOW, I'm already sweating!". I lived in Phoenix for long enough that I can deal with the heat, but when you add that humidity into the mix, that makes it intolerable for me.

Over here in Oregon we never really deal with any major humidity.

Now as for that non-Mopar water pump, I hope you're one of the lucky ones. I hope I don't see a thread from you in 6 months letting us know it failed. You'll probably be fine though, I'm sure!
 
I've been to Florida several times, and the one thing I remember is getting off the plane in Miami and being like, "WOW, I'm already sweating!". I lived in Phoenix for long enough that I can deal with the heat, but when you add that humidity into the mix, that makes it intolerable for me.

Over here in Oregon we never really deal with any major humidity.

Now as for that non-Mopar water pump, I hope you're one of the lucky ones. I hope I don't see a thread from you in 6 months letting us know it failed. You'll probably be fine though, I'm sure!
Well, like I said, the next time I'll be in a better position to fix it...
 
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Very nice video Tim, I'll bookmark this if I ever need it.
I've visited Tampa a few times in August. Going from the rented car into the building...my shirt was soaked. Loved going over to Clearwater Beach (and Hooters too)
 
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Tim, your video encouraged me to do the pump replacement myself.
Instead of using a strap wrench I removed one of the bolts of the water pump pulley and put a 0.25 inch pin in the hole catching one of the ribs on the pump housing, blocking the viscous fan drive. The fan drive came loose with a single hit on the large wrench I used on the nut. Since the old pump is a scrap item anyway I didn't bother the damage on the housing.
I live a little further south than you, the caribbean (Aruba), where the temperature never gets below 78F. My 2004 TJ had the heater core hoses removed before I got it. To save time and trouble, I tossed the heater pipe and I blocked of the heater pipe connection on the new pump with a quarter inch copper stop from the plumbing department of the local Do-It store.
Thanks for the video and the observations.
 
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In the above video, the guy states to stand the fan up vertically, so that the viscous fluid will not leak out. Is this "fact?" Because, when I received mine, it was laying flat in a box. Now, I'm curious.
 
I'm not entirely sure. I've never heard of a viscous fan before that. I just stood it up because it was easier to keep it out of the way.
 
Anyone know which hole the longer bolt goes in for the water pump? 2004 TJ

My boys removed it but did not take note
 
Tips from an amateur mechanic and first time Jeep owner.

I had my water pump go on me Saturday afternoon (coincidentally, on the way to a Jeep event, but thankfully, not on the trail). I've done water pumps in other cars before, so fortunately, I didn't go into this blind. For step by step instructions, I more or less followed
from Youtuber ChrisFix. But even so, here are my observations on the process.
  1. Hydrate
  2. Fan & Fan Clutch Removal: remove serpentine belt first, remove upper radiator hose, use an 18" pipe wrench on the fan bolt, and a strap wrench on the water pump pulley, strike pipe wrench with hammer (regular carpenter's hammer, not BFH) to knock loose, have patience & be persistent, don't try to muscle strap wrench and pipe wrench together unless the strap wrench is heavy duty, or else you may pull out the rubber strap. Wait until nut is loose before removing fan shroud, undo fan nut last and remove as a group. Expect to lose at least some skin during the process. Celebrate all the new space you have to work in, it'll be your last celebration for a short while.
  3. Hydrate
  4. Pliers, Channel Locks, Vice Grips Or Witchcraft: When it comes to hose clamps, especially the larger diameter ones, use the right tool for the right job; the wrong tool takes entirely too long
  5. Hydrate
  6. Make A Hole: Don't forget to remove the top idler pulley, in order to free up the metal pipe on the water pump
  7. Hydrate
  8. Leverage: Be sure to remove hoses while parts are still securely fastened to the engine; you'll get much better leverage on them, and the same goes for putting them back on.
  9. Did I Mention Hydrate? It's summer, and I'm in Florida.
  10. Appreciate The Little Things: When it comes time to remove the water pump and thermostat housing (you are replacing the stat also, aren't you? You really should), enjoy the relative ease in which most of the bolts come off. You will never get this opportunity again.
  11. Working In The Rain Does Not Count As Hydrating: Though as long as the thunder stays on its side of the playground, it can be refreshing (once again, Florida)
  12. Gasket Mating Surfaces: It doesn't matter how long every other task takes, when you're ready to clean the gasket residue off the mating surfaces, TAKE YOUR BLOODY TIME!!! Everything else can look like a pathetic train wreck; in contrast, this needs to be perfect. Not following this rule means you'll be doing most of these steps again pretty soon.
  13. Workspace Maintenance: Keeping the kiddie pool between the car and the front door of the house can make an effective detour between tasks.
  14. Sealants: Any bolts or other fixtures that act as a water-tight pressure seal will need teflon thread sealant; you can either use the liquid stuff, but I've found that teflon plumbing tape works as well, and makes less of a mess.
  15. Time Management: Don't look at your watch; far more time has passed than you had originally planned for, and you really don't want to know specific details on how much.
  16. Torque Settings: learn them, love them, obey them, or else you do something random like, oh, I don't know, snap the thermostat housing in half and have to fork out $12 at the auto parts store for an emergency replacement (hypothetically, of course). See below for details.
  17. While You're At It: Wouldn't be a bad time to change your serpentine belt, either.
  18. Wrapping Up: By this time, you should be thinking less about a shower and more about somebody just hosing you down in the yard.

Torque Settings:
Thermostat housing bolts: 2004 2.4L - 28 N-m / 250 in lbs
1997-2002 2.5L - 18 N-m / 13 ft lbs
1997-2006 4.0L - 18 N-m / 13 ft lbs
1997-2006 any others - 20 N-m / 15 ft lbs
Water pump bolts: 2004 4.0L - 23 N-m / 200 in lbs
2004 2.4L - 12 N-m / 105 in lbs
1997-2002 2.5L - 31 N-m / 270 in lbs
1997-2006 4.0L - 31 N-m / 270 in lbs
any other 2.5L & 4.0L - 30 N-m / 22 ft lbs

What is the .stat?

  1. Appreciate The Little Things: When it comes time to remove the water pump and thermostat housing (you are replacing the stat also, aren't you? You really should), enjoy the relative ease in which most of the bolts come off. You will never get this opportunity again.
 
What is the .stat?

  1. Appreciate The Little Things: When it comes time to remove the water pump and thermostat housing (you are replacing the stat also, aren't you? You really should), enjoy the relative ease in which most of the bolts come off. You will never get this opportunity again.

The thermostat.