CX-9 Water Pump Replacement DIY Guide

wow, just wow, amazing how to write up Thaumaturge, I know a lot of fellow members will really appreciate this, thanks for taking the time to do this. much appreciated !
 
Thanks, you are welcome.

I got a little carried away, but figured too much was better than too little.
 
I have a question for the op. I went to rock auto and under the pentosin A2 coolant it says for vehicles that don't use FL-22 coolant. They also have a pentosin A3 coolant which is premixed but the color is blue and it says for vehicles using FL-22 Coolant. Which is the correct one?
 
just a suggestion.... why not just stick with Mazda brand (no mixing) no guesswork......
costs a little more, but at least you have peace of mind that it's the same fluid Mazda designed for....also, same color if that matters...
for $8 more, I think it's worth getting OEM



 
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Why is it more expensive from amazon. I called the dealer an hour ago and he quoted me 26 dollars for the pre-mixed. I thought it would be cheaper through amazon.
 
Accidentally deleted my edited post...

In short, buy Motorcraft Specialty Green VC-10-A2 from Ford or Mazda F22 Long Life. You can also find Beck Arnley or Zerex products with F22 on the label.

You want to use P-OAT non-silicated green formulations. I don't believe there's any issue with Pentofrost A2, but I will research it further to be certain.
 
Pentosin Antifreeze Update

Kornholio and Rock Auto are correct!

I spoke with Pentosin tech support today (very nice folks BTW) and they confirmed that the FL22-compatible product to use is the Blue A3. It must be used only after a complete flush. They apologized for the lousy info on their bottles and website.

Pentosin A2 is indeed for older Mazdas NOT using FL22.

Since my water pump project is only a couple weeks old, and there was precious little original coolant left in the system, I am not too concerned with gunk buildup or seal damage.

Looks like I will be flushing and replacing my coolant today with a F22 product. Yay! I will now have one heck of a clean coolant system.
 
For those looking to spend a few fun-filled hours changing out their Water Pump, VVT, Timing Chain on the 3.7L engine, here's a 40 page guide for you. This project was done on a 2008 Touring FWD

Please let me know if you find errors or omissions.

I have included the service manual pdf as well.

https://www.dropbox.com/sh/yjma0fz8erwwot0/AABFWhv7jUDn-E1Fl669LHUja?dl=0

Thanks for the write-up!! If I can't get this done under warranty I'll tackle it myself.
Was this preventative maintenance or did your waterpump fail?
 
Has Ford/Mazda changed the waterpump design to have a better seal? Or are we expecting to replace the waterpump again after 70k miles?
 
Thanks for the write-up!! If I can't get this done under warranty I'll tackle it myself.
Was this preventative maintenance or did your waterpump fail?

You're welcome.

This was done as preventative maintenance although I did suspect I had a VVT problem (I did) that would also require the same tear-down, so I went for it for both peace of mind and troubleshooting reasons.

In looking at the old and new water pumps, I saw no change in the seals unless the material is different. The only change that is obvious is the number of impellers with new pumps having more - both types are still plastic.

IMHO, the main problem is unlikely to be the pump outer seals anyway, but is almost certainly the water pump bushing failing over time as it is under tension from the timing chain. There are pictures on the web of catastrophic failure in this engine where the impeller actually came into contact with the timing chain cover and sent impeller pieces flying. That scenario would lead one to believe the bushing is likely the weak link.

Given that Mazda and Ford both charge a $25 core charge to encourage you to return the pump for refurbishing, I suspect they are pressing in a new bushing and impeller assembly while changing out the outer seals. In my case, the outer seals were intact with only one questionable hot spot. Again I had no leaks before replacement and the bushing and sprocket had no play in them at all. I actually toyed with the idea of putting the original pump back in, but the seals were crushed pretty well after 8 years, so I did not.

In short, yes, you'll likely have to still watch for signs of leakage and change the pump again in another 70k miles. I know that's the path I am following.
 
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