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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Water Pump Troubles

  • Thread starter Thread starter TrueBlue03
  • Start date Start date Feb 26, 2008

TrueBlue03

Member
Dec 9, 2003
372
3
18
Bay Area, CA
Feb 26, 2008
#1
  • Feb 26, 2008
  • #1
My water pump just went out on me for the 3rd time in the past 8 months. maybe i'll be luckier with number 4? pshh.... I am using the OEM Motorcraft waterpumps everytime. Ever since the intake manifold cracked, my car has been on a downward spiral, which pains me as it only just passed 40,000 miles a month ago.

The first waterpump went bad after my intake manifold cracked, spraying out all the coolant.
The pump ran dry and cracked something enternally... I then had the water pump replaced.
The next two crapped out on me 2 months after the first failed, then again 7 months later (last night).


Both the 2nd and 3rd water pump leaks happened in the same sequence:

After driving for for about 15 - 20 min, I slow down as i pull into residential areas and parking lots to park the car. The waterpump would begin to leak as soon as i began to park the car right before i shut off the motor... the second time the leak started as i was pulling into a parking garage. In both cases, within 30 min of parking the car, i came out to find that nearly all of the car's coolant had drained out of the front of the waterpump. (not sure what its called...the smaller circle indentation on the front of it about the size of a quarter.) This leads me to believe it has something to do with the engine heating up and cooling down, considering its happend as i was parking it or shutting it off

Does anyone know could be causing my waterpumps to do this?
I had it done by a mechanic, not myself.
Any help would be much appreciated, because at this point, i'm thinking about returning her to stock, and selling everything including the new stuff i havent installed yet
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Feb 26, 2008
#2
  • Feb 26, 2008
  • #2
theres no sealant or gasket really. theres like 4 bolts an an o-ring. at least its covered under warranty, assuming its motorcraft and you are within 12k miles. wht type of coolant are they running?
 

TrueBlue03

Member
Dec 9, 2003
372
3
18
Bay Area, CA
Feb 26, 2008
#3
  • Feb 26, 2008
  • #3
yea the o ring. not gasket sorry. corrected.
But whats weird to me is that its not the part leaking. Its leaking from the center. Both of the pumps replacing the original have leaked from the circle indentation on the front of the waterpump.

This time i actually didnt ask what they put in. I'll find out tomorrow. As for the warranty. Ford has given me 3 now in 7 or 8 months. Thats not my main concern....its that the car is deemed unreliable now.

Im dredding the next time it decides to dump all the coolant out at 10:30 at night, 20 miles away from home, and I have to wait 1 - 2 hours for a tow.... all while in midterms week
 

RandyStinchcomb

New Member
May 25, 2005
1,159
3
0
Randallstown, Md
Feb 27, 2008
#4
  • Feb 27, 2008
  • #4
check your pulleys and the belt tensioner...these pumps are pretty-much bullittproof, so I'd look at something else being off center and causing an extra load on the waterpump bearing and seal....
 

TrueBlue03

Member
Dec 9, 2003
372
3
18
Bay Area, CA
Feb 27, 2008
#5
  • Feb 27, 2008
  • #5
thats what i thought...pretty durable

i'll check it out, but no one has answered my question....what is the function, if any, of the circular indentation with a hole, that all the coolant is draining from?
 

nyuk98gt

15 Year Member
Oct 10, 2000
1,427
6
79
Chesterfield, MO
Feb 27, 2008
#6
  • Feb 27, 2008
  • #6
TrueBlue03:

Is the hole about 3/8" dia.? I believe that is a weep hole, a 'tell-tale' to warn of impending seal failure. What's supposed to happen is a drip or slow ooze comes out, you see it and can swap out the pump before catastrophic failure.

First things first: check belt routing and the health of the tensioner. If there is some extra load put on the pulley (tension is too high?) then this will wear out the bearing quicker and then the seal will fail.

It could be a faulty seal, right from the factory. Maybe they got a batch and you happen to get 3 out of the same lot?

Next, are you specifically asking for an '03 pump? I know there should not be any differences from late model to late model but I suggest that you get the same part number as the original. Randy would have to tell you if this is bunk but the pumps might "look" the same until you measure all the internal dimensions. Maybe you should order the next new pump from Randy (I don't get a commission) just to get a pump from a different lot? Just a thought.

Lastly, I'm with you about damage being caused by the thermal growth. If there is not enough clearance in the pump housing for the impeller (when things get hot), the impeller may push into the wall and this would stress the bearing. Theoretically, the whole area should be at coolant temperature, 180 or 195 F, whatever your t-stat is set to open. But, we can think it is possible to have a temperature differential, even if it is a transient thing (i.e.--happens until everything warms up to the same temp).

It would be a pain in the rear end but you might try "dry fitting" (no o-ring) the new pump into the block but after you've put the impeller in a shallow pan of boiling water to get it warmed up. If the impeller doesn't turn freely when the warm pump is put in place, then there is a dimensional error in the part (not enough clearance). If it turns freely, I'd have to go back to the bad seal batch argument.

HTH,

Chris
 

TrueBlue03

Member
Dec 9, 2003
372
3
18
Bay Area, CA
Feb 27, 2008
#7
  • Feb 27, 2008
  • #7
Thank you for that very very helpful info

and yes, it is about 3/8" diameter... that would be the weep hole...the hole where the coolant drains out. Except there is no slow drip or ooze, only a catastrophic failure every time. lol.

It happens all at once. It starts dripping rapidly then intermittently turning into a full stream of coolant pouring out of the weep hole. You and RandyStinchcomb have made it very clear to me that something could easily be wrong with the belt and tensioner. thanks for pointing that out. I will take a closer look at both...that seems like the most logical reason why multiple pumps have failed.

Also, both the first 2 pumps came from the same Ford dealer within the same 2 month period. It could very well be a bad batch or something. Another question...after these failed, i've let Ford know about it,, and they have sent replacements under the warranty for their waterpumps... Could it be possible that when they take back the broken ones, that they just open them up, rebuild them or correct the malfunctions, and re-sell them as new? I didnt get a chance to see the supposedly 'new' pump they sent this time, but it was sealed in a Motorcraft box

Also when i talked with the Parts department, they told me that for the 2003 4.6L 2v there were TWO water pump part numbers listed in their computer. There was an 87mm and a 65mm.... which the parts guy described to me as the distance from the outside edge of the pulley straight back to the block (in other words, how far the pulley sits out, if that makes any sense.)

If i had the means, that boiling water test would be a very good way to test what you're describing.
Once again, thanks for all your info. Exactly the stuff i was interested in hearing I really appreciate it, and will be spending the weekend attempting to diagnose this annoying problem i keep having
 

nyuk98gt

15 Year Member
Oct 10, 2000
1,427
6
79
Chesterfield, MO
Feb 28, 2008
#8
  • Feb 28, 2008
  • #8
TrueBlue03:

You're welcome. You'd have to ask Randy for confirmation but I believe that Ford sells new parts as just that, new parts. Not a lawyer but parts have to be labelled "remanufacturerd" if they are not new pieces. There are two "snouts", a long one and a short one. Again, good question for Randy. (I thought the short one was for NPI and the long one for PI engines but this, obviously, is incorrect since there are both lengths for an '03 [PI] engine).

If you have a frying pan, you can dunk the pump in some boiling water, wrap it in a towel, and run out to the car to test fit the pump. Evans (evanscooling.com) makes a high performance water pump, too, for our cars. You might give that a try if there is another failure (I sure hope the next pump works out for you).

GL,

Chris
 

TrueBlue03

Member
Dec 9, 2003
372
3
18
Bay Area, CA
Jul 28, 2008
#9
  • Jul 28, 2008
  • #9
Well.... im reviving this old thread because i got to the bottom of the problem...

I went to my dads mechanic friend two days ago and he guessed it on the fist try. We went ahead and tested the coolant resevior and there is exhaust in my cooling system...

So.... i've got a leaking head gasket or my heads are warped. Good times....


When the *REVISED* (aluminum crossover) intake manifold melted, the car overheated instantly causing the damage.
Water pumps keep failing because too much pressure builds up in my cooling system and pours out of the water pump's weep hole.
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
24
58
Jul 28, 2008
#10
  • Jul 28, 2008
  • #10
Oh ~~~~....

How the hell did the intake manifold melt???



Sorry to hear about that man.

Whats your plan of action going to be?
 

TrueBlue03

Member
Dec 9, 2003
372
3
18
Bay Area, CA
Jul 28, 2008
#11
  • Jul 28, 2008
  • #11
the car had 39 or 40k miles on it.... the intake manifold plastic under the aluminum crossover melted at the thermostat housing and blew out coolant everywhere...

i replaced the intake manifold, thermostat and multiple water pumps and have been driving her for a year now with a leaking headgasket or head damage. Ford wouldnt do a damn thing because my intake manifold is the "Revised Version."

that stock plastic manifold is a joke...
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
24
58
Jul 28, 2008
#12
  • Jul 28, 2008
  • #12
Man that REALLY sucks to hear.

Hope the damage is minimal and you get it all worked out...

I'd definatly keep it though, your car is a work of art...
 
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