Is Water Pump Replacement Urgent / Are Failures Common?

[zakiu]

I'm looking at purchasing a CTSC'd '00 that had it's timing belt done around 8 or 9 years ago, so it is due. The water pump is the original pump from '00. It has 45k miles total and has only had around 10k miles put on it since the servicing was done, and it has been garage kept in socal the entire time. I plan on doing the timing belt and water pump (along with other associated items, such as the hoses, gaskets, balancer, plugs, valve adjustment etc.) in a month or two, but I am nervous about driving it for that time.

I'm not worried about the belt lasting a few months, but I am a little concerned about the water pump since it is 19 years old now. I keep reading that if the water pump fails that the timing belt destroys the engine. I know with a TB failure, it is immediate, unpredictable, and catastrophic given the interference engine. That said I don't understand if the water pump is so immediate or catastrophic. Half the posts say change it as it will fail without warning and the other half say that it will leak, make noise, overheat, etc. before it destroys anything.

In my experience, all one can do is look at the cars and their specific designs. For example- on the E36, the water pump explodes on all of them sooner or later due to the plastic impeller getting brittle. I've never heard of a failed pump on an S2000. The NSX sample size is small and most people probably change their pumps at 9-15 years at the worst, so I can't imagine there are too many cars running on 20 year old water pumps at this point.

Does anyone on here happen to have any knowledge about how worried I should be? I figure the odds are low over 1-2 months of driving, but given that it is supercharged, I'm completely uncertain.

Roman at Niguel Motors says he wouldn't even be able to take the car in for another 3 weeks and I'm certainly not taking it to Autowave given their bs quotes ($3500 for TB/WP and over $7000 for that plus hoses, gaskets, valve adj, plugs, etc.). That said if anyone has a good mechanic near westside LA they could refer me to, I'd appreciate that too.

 

[goldNSX]

If it was my car I wouldn't be worried about driving it for next 1-2 month. The CTSC doesn't add more stress on the TB/WP. If you heared unusual noises from the engine or if you detect the smell of coolant in the engine bay it might be a different story. The problem is that the CTSC makes it difficult to detect other noises.

I'd be more worried about the fuel system not being fully capaple to deliver the required amount of fuel CTSC urgently needs if the car has been sitting for an extended time.

 

[zakiu]

Thanks. It doesn't seem to have been sitting consistently for any specific duration since the weather down here is pretty consistently good. I don't smell any coolant at all. I have noticed some kind of weird sound when I get onto the throttle (not the supercharger whine). It's hard to describe the sound - but it only occurs for a brief quarter to half second when I press the throttle. I don't remember it exactly (it has been a couple of weeks since I drove it) but it sounds like a blurb. He mentioned it has sounded like that for a long time and from what I remember it may be normal?

 

[nis350]

I think it is fine to drive it locally. water pump failure usually starts with slow leaks that you can detect easily.

However, I am a bit puzzled that the water pump was not replaced along with the time belt.

 

[goldNSX]

Maybe the car had very low miles back then... WP are said to be designed to 150k+ miles. Regular coolant changes make it easier for the WP to reach that high no.

 

[Old Guy]

Maybe the car had very low miles back then... WP are said to be designed to 150k+ miles. Regular coolant changes make it easier for the WP to reach that high no.

++ on maintaining the coolant in good condition.

In the good old days when water pumps were driven by the fan / alternator V belt and you adjusted tension by cranking on the alternator and then tightening the retaining bolt, it was really easy to overtighten the belt which put a lot of lateral stress on the water pump bearing usually leading to wear on the bearing and seal and subsequent leaking / noise from the bearing and seal. The drive arrangement of the NSX pump pretty much reduces that over tensioning risk. Keep the coolant fresh and the pump will likely enjoy a long life. Since I have been on Prime I have no recollection of anyone ever suffering from a water pump failure. Of course, I don't ever recall hearing of a timing belt failure.

Plastic impellers on the BMW water pump just strikes me as bizarre.

 

[goldNSX]

Since I have been on Prime I have no recollection of anyone ever suffering from a water pump failure.

They can go bad like in my case when we detected quite a noisy WP bearing at 75k miles and 17 years. I couldn't hear it in the cabin or in the engine bay but when I turned it by hand it was clear. It was still the orginal one. The dealer choose not to change it after 10 years. Not sure how long it would have lasted but we changed it anyway.

 

[Old Guy]

They can go bad like in my case when we detected quite a noisy WP bearing at 75k miles and 17 years. I couldn't hear it in the cabin or in the engine bay but when I turned it by hand it was clear. It was still the orginal one. The dealer choose not to change it after 10 years. Not sure how long it would have lasted but we changed it anyway.

Now you have made me paranoid :smile:! My car is 19 years old with the original pump and has about 75 k miles on it. I was planning on replacing the pump next year when I have the timing belt done because it would likely be 2028 before the belt gets done again and 28 years might be pushing it on pump life.

Its probably splitting hairs; but, you didn't have a pump failure. Your pump was showing signs of wear which all pumps will demonstrate. Perhaps the no record of outright failure on Prime (leakage or obvious noise) is a result of the tendency of people to replace their pumps on a pre-emptive basis, much like the timing belt.

 

[goldNSX]

Now you have made me paranoid :smile:!

I don't understand the difference between the two intervals Honda states:
- in the service booklet it says every 6 years/?? miles, whatever comes first
- in the SM it says to replace it after 90k miles without any years noted

I know of a lot of first Gen cars with the TB done after 10 years and nothing happened.

Is the 1st schedule on purpose dealer friendly to keep the workshop busy? Is Honda fearing losing its good reputation for their reliable engines if a TB breaks due to not being changed? I don't know. They are taking into account every worse condition the engine faces and reduce the interval to the minimum. If you know that your engine doens't face all that extreme scenarios why not entending the interval?

I for myself decided the stretch the interval up to 10-12 years, knowing how the car is driven. But after that time I'm doing a complete job with everything included (the AutoWave $7000 option). Extending the interval is in the responsability of the owner, of course.

I'm not familiar with F-cars. The early ones had to replace the belt every 3 years. Does it blow up if you extend it significantly? I guess it all depends on the usage of the car.

 

[drew]

Somewhere Kaz states that JDM folks tend to ignore time and only replace on distance milestones. I can envision quite a few 30 year belts currently on cars being driven now. Worse there is no date code that I can find on Honda timing belts...

Water pumps tend to give a LOT of warning before they fail catastrophically: a lot of noise and dumping coolant. In my experience, you should get a quick plan to replace once it starts leaving drip spots on the ground and stop *immediately* if it turns into the tinyiest of streams. It is usually after continuing to drive while ignoring a tiny stream of coolant and filling up the radiator a couple of times that the water pump will eject the pulley axle...

 

[Old Guy]

The North American service manual for the 1997+ cars specifies 105,000 miles / 7 years. By the time mine gets done the belt will be 10 years old. However, my car has definitely been pensioned out (like an old race horse) and has a pretty relaxed life. You have to know that when Honda gives you a recommended service interval on something like a timing belt it will definitely be on the very conservative side.

From what I have seen on worn timing belts, outright failure where the belt separates would be a very extreme case. My old neighbour's Fiat 128 did have a complete belt separation at less than the recommended maintenance interval. Only case that I am aware of and was probably due to a manufacturing flow because he was not an aggressive driver. I think the more likely issue is wear on the tooth surfaces with the possibility that it might contribute to a tooth hop on a botched shift or something like that. The belts contribution to the problem might not get recognized because the problem was attributed to the driver botching the shift.

 

[zakiu]

I don't understand the difference between the two intervals Honda states:
- in the service booklet it says every 6 years/?? miles, whatever comes first
- in the SM it says to replace it after 90k miles without any years noted

I know of a lot of first Gen cars with the TB done after 10 years and nothing happened.

I for myself decided the stretch the interval up to 10-12 years, knowing how the car is driven. But after that time I'm doing a complete job with everything included (the AutoWave $7000 option). Extending the interval is in the responsability of the owner, of course.

An interesting note - I'm not from CA and noted years ago that many manufacturers require timing belt changes at 60k. The noteworthy part, IIRC, was that CA required by law that timing belts last 90k. So on the car I was paying attention to, Mazda recommended 60k service on the Miata TB in 49 states and a 90k service in CA. The timing belt was manufactured to last past 90k miles, but Mazda specified a shorter interval. On a non-interference engine. Sooooo...your guess is as good as mine.

 

[goldNSX]

An interesting note - I'm not from CA and noted years ago that many manufacturers require timing belt changes at 60k. The noteworthy part, IIRC, was that CA required by law that timing belts last 90k. So on the car I was paying attention to, Mazda recommended 60k service on the Miata TB in 49 states and a 90k service in CA. The timing belt was manufactured to last past 90k miles, but Mazda specified a shorter interval. On a non-interference engine. Sooooo...your guess is as good as mine.

Thanks for the interesting info. Sometimes the manufacturers get incredibly 'inventive'. Icing on the cake would have been to design a different version of the part for CA and price it accordingly. On the other hand the weather esp. in south california is mild and pretty ideal for any car.

I like the image of a 'pensioned out race horse' which Old Guy mentioned. In my case it's about to reach that state for the car and the driver soon. Easy miles are on the other extreme Honda has to define the maintenance interval. So no worry to extend the interval IHMO.