Waterpump leak.

[29Rat]

2003 4.0L, replaced the waterpump about 7 times in the last year, along with a new tensioner, fan hub, and fan blades. And a pressure cap, and fresh coolant each time. Still leaking out of the weep hole, the waterpump shaft seal, tried different brands, motorcraft included. Really pissing me off. What else am I missing that would cause a water pump to fail?

 

[Drewmcg]

I've never heard of this before, with several years on this forum. No offense, but how confident are you that the leak is from the pump?

I replaced the water pump on my '02 XLS 4.0L SOHC when I did the timing chains, just b/c I was in there. Where's this "weep hole" that you refer to? (I'm aware of weep holes on other water pumps, but not this one. 2002 FORD EXPLORER 4.0L V6 Water Pump | RockAuto .) Can you send a photo?

Also, are you saying that coolant is leaking out of *both* the shaft seal and the weep hole? Or different leak paths on different units?

If I had to guess, the leak is coming from somewhere else and leaking down the front of the engine/timing cover, causing you to conclude that's its a failed water pump. Could be anything from a bad hose, the ubiquitous thermostat housing leak(s), or bad head gasket. Either that our you have a bad/warped/cracked timing cover.

 

[ptf18]

7 times? Gee... I'll be interested in hearing what the fix is

 

[29Rat]

I've never heard of this before, with several years on this forum. No offense, but how confident are you that the leak is from the pump?

I replaced the water pump on my '02 XLS 4.0L SOHC when I did the timing chains, just b/c I was in there. Where's this "weep hole" that you refer to? (I'm aware of weep holes on other water pumps, but not this one. 2002 FORD EXPLORER 4.0L V6 Water Pump | RockAuto .) Can you send a photo?

Also, are you saying that coolant is leaking out of *both* the shaft seal and the weep hole? Or different leak paths on different units?

If I had to guess, the leak is coming from somewhere else and leaking down the front of the engine/timing cover, causing you to conclude that's its a failed water pump. Could be anything from a bad hose, the ubiquitous thermostat housing leak(s), or bad head gasket. Either that our you have a bad/warped/cracked timing cover.

It is for sure coming out of the weephole, when I refer to shaft seal leak, I am referring to the water coming out of the weep hole, indicating a shaft seal leak. I am positive in that due to the fact that I have washed it off, and pressure tested it, along with having the engine running, and clearly see the water leaking out of the weephole itself. Now I am not 100% positive that it is the weephole on this leak, because I haven't pressure tested it yet, but visually with the car running water is coming out of the weep hole. I have been washing it off and pressure testing it each time though, and will do for this leak too, even though it feels redundant at this time. Along with pressure testing the cooling system, I have pressure tested the coolant reservoir cap, rated at 16psi, popped at 15psi on my gauge.

Here is a photo of the weep hole, https://i.imgur.com/oYrj3c9.jpg , more of a cavern than a hole on this style of water pump haha.

 

[Number4]

Make sure you aren’t having a harmonic balancer issue. Common on the late model 4.0. Will eventually fly off. Look through the forums here to find discussions on it.

 

[Drewmcg]

I like Number 4's thought, though you'd think there'd be a more immediate/audible/visible sign that the serpentine belt out of whack due to failing harmonic balancer than destroying 7 water pumps!

Assuming that you're not repeatedly using cheap, aftermarket crap water pumps, I'll go back to my theory of a warped or otherwise defective front timing cover. It makes more sense to me that when you torque down all the water pump bolts to that cover, you wind up twisting/flexing the pump somehow out of plumb, causing abnormal stress on the bearing, resulting in premature failure.

You can get a replacement cover @ Rockauto, or maybe find a cheaper solution on Ebay or a junkyard. Like I mentioned, this is not a common problem (I've never heard of it), so I wouldn't hesitate to use a junkyard part.

 

[29Rat]

Hmmm good suggestions for sure. The original motor had 200k miles on it before the timing chain gave out, and had the same waterpump issue as this 100k mile motor does. Only thing I swapped from old to new motor was alternator and a/c compressor, as they were both newer, along with fan hub and fan, as the fan hub was bad on the used motor, and fan size was different. I did do a visual inspection of the harmonic balancer before installing the motor, but will take a gander at it when I have a chance to work on it this weekend. Also odds of both timing covers being out of wack? When I pulled the used motor I used that waterpump as it was not leaking, and did not remove the waterpump, but I did use my fan hub and fan as the. That's why when that wasterpump failed I replaced the fan hub, fan, and belt tensioner, as the tensioner was looser than a new one, and the fan hub was cheap. I thought that solved my problem until now.

Idk, need to pressure test the system when I get a day off in a few days. I'll keep ya posted, but 99.9% sure it's that weep hole.

 

[29Rat]

Pressure tested the system today, as expected it was the weep hole. Went to advancedauto and got a refund of my money from their Driveworks water pump. Went to O'reilly's and picked up a Murray water pump, brand new, not refurbed, and a couple of different brands of stop leak... just kidding, I'd never use stop leak. We'll see how it lasts. Even torqued it down this time, never torqued and external water pump before, but what the hell, doesn't take that much more time. Also, the harmonic balancer looked good, no pushed out rubber, or cracking. Thanks for the help!

 

[29Rat]

Well, that Murray water pump lasted the longest. January 13th and it failed... leaking out of the weephole. Thinking of using a different coolant, currently using green, what is the recommended coolant? Maybe the green just isn't compatible with the seal, but you'd think the aftermarket waterpump would use a universal coolant resistant seal. Also thinking of testing my luck with a Motorcraft one, unless I can find that Murray receipt and it's still under warranty. Just figured I'd post back here in the event someone else has the same problem as I do.

 

[Number4]

It’s near impossible to have that many defective pumps.
There has to be a mechanical issue with the front of the engine that’s causing the issue.
Fan blades are okay?

 

[donalds]

I went through 5 yes 5 new gates and other water pumps when I got new engine
Everyone thought it was a problem with the engine it was not
Replace the pump with a motorcraft and replace the pulley and fan clutch
Fill the pump with fluid let it soak overnight
Use prestone fluid DONT ROTATE THE PUMP BY HAND
Problem solved
This is what worked for me I bought my pump from rockauto $75

 

[Number4]

I went through 5 yes 5 new gates and other water pumps when I got new engine
Everyone thought it was a problem with the engine it was not
Replace the pump with a motorcraft and replace the pulley and fan clutch
Fill the pump with fluid let it soak overnight
Use prestone fluid DONT ROTATE THE PUMP BY HAND
Problem solved
This is what worked for me I bought my pump from rockauto $75

How do you know it wasn’t the fan clutch?

 

[donalds]

First wp I just did the pump second time a new pump
Pump #3 I replaced the fan and pump
#4 pump and clutch #5 I replaced the pump with a motorcraft and all is good

Use name brand coolant

All this on a new remanufactured engine
Believe me it was a ***** I will never buy another aftermarket pump again never
Replace it all and call it a day imo
EDIT... I used a Hayden clutch and a motorcraft fan

 

[29Rat]

Forgot to reply to this.

I should have filled the pump when I installed it. Next time I'll do that. I did bleed the system really well this time by squeezing the upper radiator hose, which I always do, but I didn't have to top off the coolant after the first start this time, which means I got 99% of the air out.

Fan clutch is newer, and still good. Fan blades are off of the 2005 engine that I swapped into it after the 2003 engine jumped time. 2003 fan blade had a chunk out of it, hence the swap. Tensioner was done w/ the clutch.

Did use prestone green fluid this time vs the supertech green. Hope that helps. I use supertech green and sca additive in all my vehicles with no issue, but this may just have a different type of seal that isn't compatible with something in the supertech.

This pump was a murray (warranty), but i've used motorcraft, gates, and whatever advance auto's house brand is (can't recall the name at this time)

We shall see, hopefully it lasts until I sell it, transmission goes out, or the motor jumps time and I scrap it. (not worth my time or money to do timing chains or rebuild the transmission).

I do love the '03. ride is smooth, drives well, interior looks really nice, and the seats are very comfortable. Even with 250k miles a minor detail and a passenger side seat bottom (need to check the junkyard) and interior would look new. The only thing I dislike about the car is the rear end whine/groan, but that seems to be normal, and has been like that since I bought the car at 130k miles. And the auto AWD system has a slow reaction time. Probably a sensor or module getting old, or just the clutch pack clearances are out of spec, and I suppose I could dig deeper onto that, but it isn't a concern for me. Used to driving in snow and ice anyways. The fuel economy is my only problem, drive about 1000 miles a week and 15-17 mpg doesn't cut it lol. Looking into a newer 2015ish explorer whenever this one poops out, but still need to research into the reliability of them. Andddd I wrote too much lol. Cheers!

 

[29Rat]

I went through 5 yes 5 new gates and other water pumps when I got new engine
Everyone thought it was a problem with the engine it was not
Replace the pump with a motorcraft and replace the pulley and fan clutch
Fill the pump with fluid let it soak overnight
Use prestone fluid DONT ROTATE THE PUMP BY HAND
Problem solved
This is what worked for me I bought my pump from rockauto $75

Glad to hear I'm not the only one who's had a problem with pumps. This is a problem concerning two different engine longblocks, so has to be an external or accessory issue. I try a motorcraft (again) next time, only reason I did not this time around is because my other vehicle was loaned out and couldn't wait the 2-3 days for a motorcraft one to arrive in the mail, and I was not spending $350 for one at my local auto parts store, talk about price gouging.

 

[29Rat]

Waterpump leaking today... Has something to do with the cold weather, just had our first batch of 20's at night. Going to replace the harmonic balancer this time, as the front main is leaking a tiny bit anyways. Would replace with a Motorcraft water pump, but don't have the time to wait for one to ship (only vehicle), and have warranty on this WP. Also have a junkyard fan to replace the old one with, as I actually have a 2005 fan on it, as the 2003 fan was busted when I swapped in the 2005 engine. Probably order a motorcraft wp to have on hand for this winter...

I pressure tested it, for sure the waterpump shaft seal, coming out of the weep hole on the wp. Will use name brand coolant as usual also. Just thought I'd share this, and just to vent a bit.

 

[donalds]

Drop a bottle of K seal in it and order a motorcraft water pump

Never again will I buy a aftermarket . New or reman..

Only new motorcraft

 

[29Rat]

So, externally the harmonic balancer looks good. But figured I'd replace it anyways. Upon removal of the bolt, I noticed there was a ring loose inside of it. Sounds like it's specific to my 2005 motor (just did a quick search b/c I was curious, could be for all motors). Jeez. Never seen a balancer with a weight/ring inside of it, but live and learn. Going to get parts and hopefully never touch that damned waterpump again.

How to: - 4.0 Harmonic Balancer - know when it's going bad & how to fix

MODS, please "sticky" this thread... I have searched this site and have included the pertinent 4.0 harmonic balancer threads into this one, to make it easier for future reference and to help those who are seeking the proper information regarding the 4.0 balancer issues. This is a very...

www.explorerforum.com

So yeah, in conclusion, my problem is probably a bad balancer. Why the 2003 motor also went through water pumps also is unknown, possibly the same reason.

 

[TechGuru]

Make sure one is using one of the correct fluids:

This is the only stop leak I feel safe using.

 

[AidansCars]

So, externally the harmonic balancer looks good. But figured I'd replace it anyways. Upon removal of the bolt, I noticed there was a ring loose inside of it. Sounds like it's specific to my 2005 motor (just did a quick search b/c I was curious, could be for all motors). Jeez. Never seen a balancer with a weight/ring inside of it, but live and learn. Going to get parts and hopefully never touch that damned waterpump again.

How to: - 4.0 Harmonic Balancer - know when it's going bad & how to fix

MODS, please "sticky" this thread... I have searched this site and have included the pertinent 4.0 harmonic balancer threads into this one, to make it easier for future reference and to help those who are seeking the proper information regarding the 4.0 balancer issues. This is a very...

www.explorerforum.com

So yeah, in conclusion, my problem is probably a bad balancer. Why the 2003 motor also went through water pumps also is unknown, possibly the same reason.

Has your problem fixed itself finally? Or did you junk the car? I also have an 03 that's around 234k miles and it just started pissing coolant a bit. I've changed the radiator cap, flushed the coolant awhile ago (it's still green), I've verified it's not the head gasket as my exhaust manifold is dry as a bone off or on. I've made a post about this because I think I may have something else wrong than just a WP. If you could give a reply here or in my post if you've become more knowledgeable would be very much appreciated.