Is it common for water pumps to go out suddenly?


#1

I have a 96 Chevy truck that went into the shop recently for something completely unrelated, and shop owner calls me and tells me that the car is leaking radiator fluid. Later he calls and tells me the water pump had to be replaced. The car just had the oil changed a couple of weeks ago and the coolant levels were fine then. No strange noises, no high temp lights. Is it common for water pumps to just up and quit?


#2

Nothing says it “went out” suddenly. It is possible that the shop saw coolant leaking from the water pump weep hole, and that usually is a precursor to the water pump failing. And yes the leak could have developed in the couple weeks since the oil change.


#3

Pvt is reading my mind…
IMHO the shop did you a favor.


#4

A very small leak from the water pump might not change the coolant level noticeably for a long time, at first.


#5

There was no coolant level in the reservoir and radiator was halfway empty.


#6

And… here’s another thing about pressure related leaks.
it is very common…
to see only one leak at first…fix that leak …then see a second…then ( in my case ) fix that and find…leak number three !

Pressure has everything to do with each potential leak actaully leaking, the weakest will naturally be the first to give way. Then, when pressure builds anew …


#7

When was the water pump last replaced?

Water pump failure is not as common as it used to be, but they still happen, especially on vehicles that don’t have timing belts. On cars with timing belts, the water pumps get replaced every 60,000-90,000 miles before they get a chance to fail.


#8

My wife once had a water pump fail catastrophically out of the blue, so it’s certainly possible.


#9

I’ve had the bearings seize on more than one water pump, and ruin the belt. I’ve also had them come apart and have the fan ruin the radiator. OTOH, I’ve had them make funny noises for 10K miles and never leak.

If indeed the pump was leaking, they did you a favor.


#10

Yes I agree it’s a fortunate catch, naturally I’d hate for the truck to overheat!

I can’t remember if the water pump as been replaced.


#11

The reason water pumps often begin to leak slowly is because they’re constructed with a shaft, turned by a pulley, that goes through a bearing and rubber seal to turn an impellar, which is what pumps the coolant. Any rubber seal with a metal shaft constantly spinning in it will eventually lose its ability to prevent fluid passage.

The reason they’re often not noticed initially is because they’re in an out-of-the-way location visually and they begin to seep slowly, usually only when the engine is running and the shaft turning inside the seal, and only when the engine is at operating temperature and the coolant is pressurized. A typical system runs at 15-16psi (the actual number will be printed on your radiator cap).

A water pump beginning to leak past the shaft seal is common. And it does not usually portend the appearance of other leaks developing. It’s a singular and isolated failure of its own. It’s just good that the shop caught it before it became serious.


#12

Yeah they can start leaking pretty fast. More than once when I got home from my 50 mile commute I noticed the pump had started to leak and was ok before I left work. I also had two not leak but the bearing wore enough to throw the belt off. No real warning. Used to have to replace them about every year or two years at the most on the GMs.


#13

They do “go out” suddenly, but they “wear out” slowly. I did a coolant change on my Saturn, the second one in its life at 265k miles and almost 12 years old. The drained coolant was still clear and the car had never lost a drop of coolant. A week after the coolant change, the low coolant light came on and I found the water pump was leaking, just a little, but I changed it before it became a lot.


#14

Any evidence that a fan blade truck wp fails more/less often than a model where wp does not hold fan?