I have a 2004 Dakota with the 4.7 Liter v8. Just today I replaced the water pump for the 6th, yes 6th time. I have replaced them 3 times myself, and the others have been done by a reputable service center I know. I originally replaced them with OEM parts, right from the dealer and that didn't seem to matter. I've had 2 OEM pumps 2 napa, 1 from Oreilly and today from Carquest. SO..I've tried different manufactured parts and that does not seem to matter. I've also used both new and rebuilt. Most of the pumps are blowing out the seals between the engine block and the waterpump. I have also had the pumps leak out the center from the bearing shaft area. I have tried using just the inset, formed gasket that most the pumps come with now. When that didn't work, I've tried trimming that down flush to the face of the pump and using silicone gasket maker. Does not seem to matter. I have followed the sequence of tightening the bolts that the manual recommends, as well as the recommended torque on the bolts. I did realize that I had a bad fan clutch and bearing which I replaced this time also, so this will be the first pump on the truck with the new fan clutch. However, most of the failures are not out the front of the pump bearing area, where you suspect it to be if the bad fan clutch bearing was blowing it out. All of my other pullies on the truck seem to be fine. I've checked them all. The tensioner for my belt seems fine also. The only thing I can think of is that there may be some type of problem with the engine block it self, where it is out of spec and not milled perfectly flat. However, the gasket should take up any of that play, unless it was so bad the gasket couldn't correct it, in which case the fluid should be pouring out of the seal.

I'm at a loss at this point. Has anyone out there had anything remotely close to this happen? I've never had this kind of problem with any other vehicle. Any help or ideas would be greatly appreciated.

 

I will move this to the 2nd Generation Dakota Sub-Forum.

 

i dont like rtv, i use permatex #2, but i think that is not the trouble. try adding 6-8 oz of marvel mystery oil , to lube the seals/ bearings. just my idea.

 

2 thoughts..

Your bad clutch caused most of the failures. Run the truck without the fan; I have for 8 years, no issues. Even though you just replaced it, leave it off as a test. I would suspect that is the issue, at least for the times when the bearing/front seal went.

You may have a minor warpage in the face where your pump mounts. IF it fails again from the seal, not the bearing, you can check with a machinist straight edge. Or, a speed square etc. Like you said, any notable deflection would probably show a leak when standing, etc.

good luck!

 

Replace the clutch-fan with a electric fan. Get rid of that fan clutch.
Make sure the surface of the block is straight.(If you
grind on it with a 3-m disk-green,- or something as
abrasive as that, your removing metal not, just old
gasket material). When you put on the next new pump,
AFTER you make darn sure with a straight-edge the surface
is true replace ALL the bolts for the water pump with new ones.
Use RTV black or Permatex number2 lightly on BOTH mounting
sides. Don't let it tack-up or, harden. mount the pump right away.
Also,.. Check the block at the mounting area and, the bolt hole
areas closely for any signs of cracks. There is spray-on dye at
Napa, (can't remember the name) you can get that will show
more clearly any stress-cracks in the mounting areas of the block.
Good-luck. Let us know the out-come!

 

Are you using rebuilt water pumps, or new?

It's never a good idea to use a rebuilt water pump because the shafts get corroded and wear out the new seals prematurely.

 

Man....that's a tough one. But 6 water pumps replaced on an 04' Dakota??? That is not right and I think it's something more serious than a fan clutch or gasket or the type of seal you're using.

I have an 01' Dakota with over 130,000 on it and I have never had to change my water pump even one (1) time, let alone 6. (KNOCK ON WOOD). Or my fan clutch.

IF you're going through water pumps like that, I would be taking it somewhere, where they can do some pressure testing or something. Sounds like something is plugged up somewhere to me. Have you ever had your engine professionally flushed?

I'm at a loss on this one. But 6 pumps??? Over how long of a period.

 

What about fan belts?? Have you been going through those as well?? Do you have a pulley that is not perfectly straight? This may cause your belt to bind on the water pump and wear out the bearing prematurely.

I'm just throwing some idea out there for you to think about.

Sorry to hear this.

 

A bad fan clutch will take out the water pump. I had this happen to my Durango
Hopefully with the new clutch the new pump will last.

 

check anything that runs off the belt like harmonic balancer water pump If anything is out of wack it will put stress on that bearing especially if it is out of line or to tight