Mileage for water pump replacement?

Hi, all.
I’ve always heard that the water pump should be replaced along with the timing belt, and the belt should be replaced every 60,000 miles. Fine, but what about if the car has a timing chain instead, which doesn’t require replacement? When should the water pump be changed?

Only if having a problem with it.

+1 for @kengreen. I had a Jeep Cherokee that went over 200K without a water pump replacement.

@kengreen Agree; its impossible to tell when a water pump will go. I had to replace one on a 1984 Impala V8 at 156,000 miles when it started leaking. The car was well maintained, but the seal blew when the car was parked outside my favorite coffee shop after a hot summer run. The fix at that time was $250 or so. AAA paid for the towing.

Others have gone much longer so it is an unpredictable event.

The 60k timing belt change interval hasn’t been around for over 10 years. I’ve yet to see one less then 100k miles these days.

But back to the original question…A water doesn’t need to be changed unless there’s a problem. The reason you’d change the pump when you did a timing belt is because the biggest cost in replacing a water pump is the labor. In most cases you have to remove the belt to remove replace the pump…so as long as you’re there you might as well replace it.

There is no rule of thumb when to replace a water pump. I have over 230k miles on my 4runner with the original water pump. Hopefully it’ll last the life of the vehicle. If not I’ll wait until it starts leaking or some other sign that I should replace it.

Leave it along unless you have an obvious issue. If you work with lots of water pumps, you can kinda tell how much life is left. If you turn a new one by hand, there is more resistance than in an older one that has worn seals and bearings. If you remove the belt and try to spin it by hand and it spins freely at all, you are ready to replace it very soon. If other scheduled maintenance puts you in the same area and you see this, go ahead and replace it.

I actually replaced one earlier today on a friend’s 1991 Geo Metro with 132k on it. Since we didn’t know the history of the car as it is new to her, I told her it would be a good idea to change the timing belt and tensioner/idler on this car. Since the water pump is under the timing belt, I decided to have her get one of those too. For $35, you have a lot of peace of mind knowing the water pump is also new. Upon tearing into the car, I noticed that the timing belt was heavily cracked and the water pump spun freely and had a small leak out the weep hole so I think both are originals and due for replacement. The nice thing about the Suzuki/Geo G10 engine is that it is non-interference except on a few rare DOHC models.

Basically, if your car has a timing belt and the timing belt has to come off to get to the water pump, by all means change it at the same time as most of the labor is getting the timing belt off and the water pump is easy from there. Some water pumps are also driven by the timing belt so definitely replace that style if your car has one at the same time as the timing belt.

Some Chryslers like the 2.7L engine have a water pump that leaks internally to the engine oil when it decides to fail. Yes, this is just another reason I won’t buy any MOPAR product. The 9 hour thermostat change on another also helped cure me of any desire to own one. Thermostats are usually easier and quicker than changing the oil but not on this Chrysler.

My 2002 Toyota Sienna, the company says to Inspect the water pump when the timing belt is replaced. At 90,000 they said it would be okay yet.

I was going to replace it anyway at 180,000, but they also said inspection indicated it was time to replace it. I am not assuming other brands have the same policy, nor that they can go 180,000 miles.

The answer to your question may depend on whether you would be doing it yourself, or if you would be paying a mechanic. I sometimes replace things preemptively, when I have the opportunity, because I don’t like being stranded, or forced to pay someone else to fix what I have the capability of doing myself just because I’m not at home with all my tools.

Case in point: A year ago, I acquired a vehicle with a timing chain from someone who made vague reference to some sort of unidentified leak, which was the main reason she decided to park it and buy a newer car. The low price accounted for this uncertain problem. Three months later, that leak finally surfaced as a failed radiator . With 150k on that rad, I was not surprised.

With the coolant drained and the radiator removed, it was a no brainer to replace all the cooling system components: hoses, thermostat, rad cap, transmission coolant lines. I also intended on replacing the serpentine belt, which drives the water pump, since I didn’t know if the belt had been recently replaced. So although there was no sign of a problem with the pump, for $40 and a few extra minutes under the car before the new belt was installed, I significantly reduced the possibility of a water pump failure at an “inconvenient” time. Inconvenient includes it’s snowing (no garage), I’m 1000 miles from home, I’m in the middle of nowhere, I’m going somewhere where I can’t afford to NOT show up, I’m making the 5000 foot climb out of Death Valley on a hot day (best done before sunrise - BTW), etc.

In other words, I’ve decided that DIY pre-emptive maintenance is a way to gain some degree of reliability from decrepit old cars…since I can’t begin to consider buying anything new. Hey, it works for me anyway. If you pay others to work on your car, wait til the pump shows a problem.


The likelihood of a water pump getting you suddenly stranded is very small, unlike a belt.
That’s assuming the cooling system is periodically checked out.
So we treat the pump and belt differently.

@circuitsmith Correct; you can’t do proactive maintenance on the water pump. It’s a “run to failure” item on a car with a timing chain. That’s a technical term (RTF) for items that cannot be “condition monitored” and where the failure does not cause a catastrophy.

The likelyhood of the pump failing is small, and many last several hundred thousand miles. And like the water heater in your basement, they start leaking before they fail completely.

On cars with timing beklts, the pump is hidden and the labor o repalce it is significant, while the pump itself is cheap. So you replace it with the timing belt.

@circuitsmith when my neighbor’s water pump failed, it caused the end of the engine.

The impeller broke, and the engine overheated.
He obviously didn’t shut it off in time.
He admitted as much.
I checked compression, and it was laughably low. I’m talking 50-60psi for all cylinders.
I told him that engine will not ever start again, without a major cash infusion, anways.

So perhaps it’s best to replace it at the first sign of a weak bearing, leakage, etc.

As I said, the likelihood is very small, not zero.

“So perhaps it’s best to replace it at the first sign of a weak bearing, leakage, etc”

That’s why I said “the cooling system is periodically checked out”.

Yes, I would replace the water pump at the first sign of failure. This way, you can do it at a convenient time such as the weekend, evening, day off work, etc. as you will still have some time to keep driving it. If the timing belt must come off to do the job and it isn’t brand new, I would definitely do that then too. Many of the old V8’s with timing chains have the water pump on the front of the engine and you just leave all those chains alone unless you believe they are failing, then this wouldn’t be a horrid time to go for that too.

On cars with chains, the pump should absolutely be replaced at the first sign of a problem. But not before. And not after the engine has had a chance to overheat.

The good news is that perhaps (and I confess, I have no data to back me) the most common mode of failure for water pumps is weeping through the seal on the shaft through which the pulley drives the impellar. I promote a routine “look see” of the surrounding areas whenever oding work on a vehicle, as well as rountine monitoring for anything unusual, like new fluid drops on the driveway or a new fluid track down the side of a component. A while back on my old pickup I was doing a “look-see” when I noticed a white crusty area on the radiator. I touched it and, to no surprise, the fins crumbled. I changed out the radiator, and when I was finished I poked my finger right through the crusty area. I caught it just in time.

It’s unfortunate that bd’s neighbor didn’t catch his problem in time.

@mountainbike The other warning is a growling noise that indicates excessive wear.

@thesamemountainbike that neighbor doesn’t take care of his cars at all.

oil changes

Nothing else

I’m a little paranoid about water pumps. Three times in my GM 3800s I’ve had the bearing wear enough to cock the pulley and throw the serpentine belt off. No leaks either time, no noise, and seemed fine and not excessively loose. Once it was 10 below out and couldn’t keep the belt on for even a minute. So that was a case of pre-emptively replacing them with new at 70-80K when convenient. Of course the three failures were on different cars and over 7-800K miles but still. Also had the leaking issues which would let you drive a little but you don’t go very far without a working water pump.

My water pump story. I was driving my 70’s Ford truck through a very small town in western Colorado (population at most 100, including the chickens) some years ago and the water pump failed. About 6 pm on a cold winter Sunday evening. Miles from my destination, and miles from any major town.

I was getting gas at the single gas pump they had there in town when I noticed the leaking, so I asked the station attendent if they had a mechanic, or if there was an auto shop in town. He said, no, they didn’t even have a garage there to work on cars, but he’d call his friends who had some tools and they’d come over if I wanted. So I said “sure”.

Well, these friends of his, I could tell they had some good general car fix-it knowledge, but they didn’t really have much in the way of tools. And it was now completely dark. And getting colder by the minute. But they were game, had some flashlights and warm clothes, and they had found a replacement pump somehow, so I said “have at it”.

I watched them work for a few minutes, then I noticed some loud music coming from a bar across the street. And lots of cars parked in the parking lot. I could tell this water pump job was going to take a while, given the improvised tooling being used. So I moseyed over across the street and went it.

It was a scene unlike anything I’ve ever seen. I’d stumbled across an honest to goodness western cowboy barn dance. All the guys were ranchhands, mostly in their twenties, cowboy boots and cowboy hats, and the gals, pretty as can be, had western style clothing, and everyone was shouting and laughing and stomping their feet and drinking lots and lots of beer.

Well, to make a long story short, I stumbled out of that bar about 2 am, and the 2 guys working on my car were just finishing. They had worked on the water pump in the dark and cold for 8 hours. They started it up, shown me it wasn’t leaking with their flashlight, presented me with the bill: $75. Parts and labor. I paid them $75 plus $175 tip. Thinking I was maybe a little over the limit to drive, I brought out my sleeping bag and slept on the front seat until morning. As you might expect, I required a major aspirin dose.

The lady at the bar where I sought out some aspirin that morning told me I’d won the “dancing fool” prize the night before! What the prize was, I’ll never know … but the water pump never leaked … and one of the most fun evenings I’ve ever had … lol