Hmm my water pump failed again!!!! Could it be the pulley?!?!

[YarisSedan]

So I just had my water pump changed less than a month ago. Now it is failed again. Could it be cause of the NST pulley? Non dampned vibration at high rpm killing the water pump? Cause i do drive my car to redline every single day. I am afraid if i take it back this time they will claim it has to do with my aftermarket parts.

[Altitude]

I've had my NST pulley on for about 6 months and 5000 miles. No problems yet. I haven't heard of any other reported problems either. It may have more to do with the abuse (red-lining) you are giving to the engine.

[Astroman]

Probably abuse. I've had my pulley on for over 50k miles and I'm doin fine.

[Tamago]

it's the pulley.

[Astroman]

If that's the case, then why is this the first problem with the water pump with hundreds of thousands (if not a million) miles by everyone using the pulleys? Redlining the crap out of a car is more likely to cause stuff to break than a pulley.

[Tamago]

Originally Posted by Astroman

If that's the case, then why is this the first problem with the water pump with hundreds of thousands (if not a million) miles by everyone using the pulleys? Redlining the crap out of a car is more likely to cause stuff to break than a pulley.

if you say so.



the ratio of water pump failures stock vs pulley tells the tale..

[advocate]

Originally Posted by Tamago

if you say so.



the ratio of water pump failures stock vs pulley tells the tale..

There are definitely quite a few people who've had water pump failures with the aftermarket pulleys.

[Astroman]

The only water pump issues I've ever had was with the ol' '71 Ford. Any mechanics you could take it to that might be able to chime in? I just find it odd I've put over 50k miles with a full pulley setup on (not overdrive) without issue. Time will tell I suppose.

[1NZYaris1]

Originally Posted by Tamago

if you say so.



the ratio of water pump failures stock vs pulley tells the tale..

Could it be due to people over tightenning the BELTS

[fmicle]

Originally Posted by Tamago

the ratio of water pump failures stock vs pulley tells the tale..

I beg to differ. This is a typical mistake people make, just because there is a correlation between A and B it doesn't mean A caused B or vice versa.

Let me explain with an example: studies show that households with more books have smarter kids (correlation between books and kids), so a mayor in Illinois thought he'll simply give away free books and make kids smarter. Needless to say, the plan didn't work. Because it's not the number of books that cause the kids to be smart, it's their parents' education, status, emphasis on school, etc. And those families are likely to have more books to begin with. So, there is another parameter C that causes both A and B to go together.

Back to our situation: people with aftermarket pulleys have more water pump failures than the ones driving stock (that's the correlation). So some people incorrectly infer that the pulleys must cause the failure.

Imagine this: people who install aftermarket parts and tune their cars are more likely to drive their cars more aggressively, therefore putting more stress on their parts than those driving stock (grandma, grandpa, uncle Jimmy).

Just remember the basic principle: correlation does not imply causation. For more details check it out on Wikipedia: Correlation does not imply causation

[PHXDEMON]

Originally Posted by fmicle

I beg to differ. This is a typical mistake people make, just because there is a correlation between A and B it doesn't mean A caused B or vice versa.

Let me explain with an example: studies show that households with more books have smarter kids (correlation between books and kids), so a mayor in Illinois thought he'll simply give away free books and make kids smarter. Needless to say, the plan didn't work. Because it's not the number of books that cause the kids to be smart, it's their parents' education, status, emphasis on school, etc. And those families are likely to have more books to begin with. So, there is another parameter C that causes both A and B to go together.

Back to our situation: people with aftermarket pulleys have more water pump failures than the ones driving stock (that's the correlation). So some people incorrectly infer that the pulleys must cause the failure.

Imagine this: people who install aftermarket parts and tune their cars are more likely to drive their cars more aggressively, therefore putting more stress on their parts than those driving stock (grandma, grandpa, uncle Jimmy).

Just remember the basic principle: correlation does not imply causation. For more details check it out on Wikipedia: Correlation does not imply causation

Wisdom

[marcus]

belt might be too tight..

[supmet]

lol @ the denial.

Guys... if aftermarket pulleys were a 100% win/win situation, we would have lightened pulleys stock.

Think about it.

[PHXDEMON]

I personally think it has to do with installation of the pulley. Check the belt it may be slightly misaligned or too tight.

[tk-421]

I just notified MikeNST about this issue. Hopefully he'll chime in soon.

[Altitude]

Maybe we can all agree it is the combination of the pulley or belt too tight and the harsh driving?

[rhino5]

Just a lightweight pulley or an underdrive pulley?

Pulley driven water pumps are really that mysterious, mechanically there's not much to fail. I'd blame shitty casting or belt tension before blaming pulley ratios.

[YarisSedan]

Well to me it just seems very strange within a month the water pump failed. And my original water pump did not fail until after the pulley was installed as well. When i changed the pulley i marked the altenator position with a white out so that it was isntaleld in the exact same position as factory. I am going to go check the tightness of the belt after the water pump was instaleld by the dealer. If it was put on way to tight and compounded with how i drive i would say that would be the cause this time. Or a combination of the pulley and overtightend.