Is my water pump bad??

[tpattgeek]

Hello everyone, this is in reference to my 07 Civic as you will see in the videos linked below. I get in it a few days ago, start it up, and it has this horrible knocking sound. I immediately took a video of it because I have no idea where to start diagnosing something like that. I get in to start driving (don't ask) and a few minutes later, I heard a pop sound from under the hood so I pulled into a parking lot. I made it into a spot and heard another pop sound. I got out, opened the hood, and all three bolts had popped off of the water pump pulley. The belt was obviously no longer spinning. I immediately turned the car off while the temp was still good. I had it towed (insurance paid) to a good third party shop that is very good with Hondas.

That night, I realized there was some type of recall for the water pump pulley bolts losing tension and breaking. I had it checked/done in 2008. I called my dealer and it was not a recall, but a "product update" that only lasted so long, and ended a couple of years ago. I was one month out of my extended warranty also, go figure. The shop said it was actually a bad water pump that caused the pulley to break. So I'm wondering how can I see if the pump really was bad? Can you do some kind of tests at home? I did see that where the pulley bolts to the pump, that circular piece was pretty hard to spin. It had a lot of resistance. I'm confident the shop is being honest, but the car has 75k miles on it and I bought it brand new and did all maintenance on it. Anyway, what do you think? Any way to know for sure if the pump went first or if it was indeed the pulley/bolts that lost tension? Videos and pics below if that will help:

http://www.youtube.com/watch?v=7HYOtM-OyJA

http://www.youtube.com/watch?v=OmiDhqVGCYc

http://i42.tinypic.com/9h06jl.jpg

http://i43.tinypic.com/b7mhc5.jpg

 

[dishdude]

It looks like the bearing in the WP went and the mounting studs for the water pump pulley sheared off. It's shot.

 

[tpattgeek]

So that signifies a bad pump is what you're saying? I guess they should have put 4 bolts instead of 3?

That reminds me of my old civic that had 4 lug bolts instead of the more common 5. Why did they ever choose 4? Just because it's minimum a small car needed? Sorry to go off of my own topic...

 

[Kool1]

The water pump should not have a lot of resistance. The only resistance from a good water pump is the seal.

Hopefully the shop changed the water pump with a factory Honda OEM pump which is probably upgraded from the original pump and won't have the same issue in the future.

 

[Donald]

If the bearing in a WP seizes what do you want to happen? Its going to break the belt or rip the pulley apart.

 

[tpattgeek]

I would think a belt disintegrating would be cheaper than the pulley falling off and breaking something else. So it's designed to break intentionally in case of a WP failure? I always thought 75k miles is pretty low for a WP failure.

 

[SrDriver]

Neighbor had the same problem with his Civic @ around the same mileage. Soon after that was repaired the alternator had to be replaced too.

 

[tpattgeek]

Thanks for the heads up.

 

[artificialist]

Originally Posted By: SrDriver
Neighbor had the same problem with his Civic @ around the same mileage. Soon after that was repaired the alternator had to be replaced too.


Would that mean that the belt has so much tension that it puts to much stress on bearings?

 

[default]

Looks like a loose bolt problem to me, the belt cannot transmit enough power to shear those bolts off if everything is torqued properly. Had it happen on my wheels before, same deal, knocking noise, then studs start snapping off. The bolts arent supposed to take any load, just provide a clamping load to maintain enough friction between the pulley and pump.

Or as I was once told by an old engineer, "You put bolts in shear, people die"

 

[Merkava_4]

Originally Posted By: default
Looks like a loose bolt problem to me, the belt cannot transmit enough power to shear those bolts off if everything is torqued properly.


Think of what that pulley is attached to - it's attached to a shaft. What is that shaft attached to? The bearing. Visualize the bearing giving way and as a result, the pulley shaking around all over the place. The belt wants the pulley to be straight.

 

[default]

Even if the pump LOCKED UP SOLID, you would either snap/squeal the belt, or those studs would have sheared FLUSH, not with one sticking out like that. If the shaft developed that much play with would throw the belt and nothing else. Tensile strength of grade 8.8 is 85000 psi, shear is typically 2/3 of that IIRC. Ain't happening.

 

[tpattgeek]

They didn't all snap at once. It happened while I was pulling into the parking lot, and there was about 1-2 minutes in between the first one snapping and the second one snapping. I really only remember hearing 2, so maybe the last 2 went at the same time. If only one bolt was loose, shouldn't the other 2 have enough strength to keep the shaft spinning straight? I guess I'm just wondering how losing just one bolt is significant enough to make the others want to snap off, unless of course the pump is putting too much stress on them... I'm just grasping at straws here, but I'm leaning toward a little bit of both... loose bolt and bad pump. The car drove perfectly fine one day, I crank it up the next day, pump is knocking.

Edit: By the way, I asked for the old pump and they gave it to me. They said the bearing was loose before they had even taken it off the car, like they pushed it and it was moving front to back slightly. I can do a video to show resistance of the bearing if that would help. If I can find out if it's a good pump, I can get the bolts tapped out and keep it as a spare or something. Think it's worth it?

 

[mattd]

Originally Posted By: tpattgeek
They didn't all snap at once. It happened while I was pulling into the parking lot, and there was about 1-2 minutes in between the first one snapping and the second one snapping. I really only remember hearing 2, so maybe the last 2 went at the same time. If only one bolt was loose, shouldn't the other 2 have enough strength to keep the shaft spinning straight? I guess I'm just wondering how losing just one bolt is significant enough to make the others want to snap off, unless of course the pump is putting too much stress on them... I'm just grasping at straws here, but I'm leaning toward a little bit of both... loose bolt and bad pump. The car drove perfectly fine one day, I crank it up the next day, pump is knocking.

Edit: By the way, I asked for the old pump and they gave it to me. They said the bearing was loose before they had even taken it off the car, like they pushed it and it was moving front to back slightly. I can do a video to show resistance of the bearing if that would help. If I can find out if it's a good pump, I can get the bolts tapped out and keep it as a spare or something. Think it's worth it?


No.

 

[tpattgeek]

OK, so how do I know this will not happen again? Since it was supposedly fixed several years ago after the problem was known, what was the actual cause of it in the first place? Bad pump design? Bad pump location? Too much stress on the pulley along with weak pulley bolts? I guess I'm just wondering with a new belt, new pump, new bolts, but ORIGINAL pulley, how likely is this to happen again? What was the weak link in the original design? Is that even known?

 

[Fleetmon]

I agree with default, I think the bolts were left loose from the original recall according to the picture.....and loose for a while. i'm willing to bet there was, at least, a slight vibration and possibly some noise before it came undone. good luck getting the dealer to acknowledge it though.

 

[tpattgeek]

I can see that happening... one of the complaints with doing it yourself if the inability to keep the pulley still and supported while tightening the bolts. I can see how and why loose bolts are common. I did have a little bit of ticking sound but figured it was my injectors or valves. It was a little noisier compared to another car like mine with even higher mileage.

Yeah, after having it towed to the shop, Honda wanted me to have it towed to them so they could check it out to see if it was caused by the original recall. But even then, it would not be fully covered since the "recall" ended 2 years ago. I did not want to pay to tow it to Honda then end up paying them double the labor only for them to say "yep, bad water pump..." 75k miles isn't a bad time for a preventative pump and belt so I'm not too bummed out. It was $394 total for Honda coolant/belt/pump/reused pulley, all Gates brand. I would pay someone 100 just to get that serpentine belt off and on LOL