Mazda cx-9 water pump

[jo552006]

Hi all,



I have a 2013 Mazda CX-9 that almost definitely lost it's water pump a couple days ago.  I left the grocery store and heard some noise from the engine.  Instead of immediately stopping, I drove for a couple miles (you know, because I'm an idiot) but noticed the temp gauge going up.  I stopped before it actually overheated, but it was heading towards the high side of the temp gauge.



I checked the oil after I parked it and it was WAAAAY overfull and very runny.  I'm about 98% sure that my water pump blew.  The engine never seized and I didn't really let it get too hot, though it did make some weird noise.  Almost like a whirring (which i had only ever heard when a water pump on a neon I had went and was machining the timing cover from the inside).



Is their any way to tell if I blew my whole engine or if I can get away with a water pump?  One person I read mentioned changing the oil and running for just a minute to listen for valvetrain/rod noises.  I would take on the water pump repair myself.

[lukebuz]

Sorry guy, if you oil is contaminated with coolant, you almost certainly have a blown head gasket.  Only real interface for oil and coolant to mix.

It's quite the job to do.  Expect at least $1K bill.

If car is otherwise reliable, fix it, keep it, and move on.

[Syonyk]

Sorry guy, if you oil is contaminated with coolant, you almost certainly have a blown head gasket.  Only real interface for oil and coolant to mix.

Not true.  Some cars have the water pump inside the timing covers, and if it leaks, it'll drain into the oil.

Is their any way to tell if I blew my whole engine or if I can get away with a water pump?  One person I read mentioned changing the oil and running for just a minute to listen for valvetrain/rod noises.  I would take on the water pump repair myself.

Get the oil/coolant mix out of there pronto - I'd be inclined to drain the oil, drain the coolant, change it with the cheapest crap I could find, run the engine for a minute or so, drain the oil again, and then work on stuff.  Gallon jugs of Walmart's Best type oil.

The good news is that you've had oil pressure, so I wouldn't expect much in the way of rod/bearing damage.  Don't leave the coolant in, though, it's not very good for bearings and cams.

You might do a compression test while you're in there, just to see if it is a head gasket - if it's blowing that much coolant into the oil, you'll have a cylinder way, way low on compression.  A leakdown test would be better for finding a bad head gasket, but most people don't have the equipment for that.

Worst case, you'd have to swap a junkyard motor in, but if you're doing the water pump, I assume you could do that as well.  Good excuse for an engine hoist if you don't have one!

[jo552006]

Agree with you 100% Syonyk.  I did just that.  I drained the coolant, (to prevent further contamination) then I drained the oil, put in about a cup of K-1, then 5 quarts of oil.  Ran for a small bit.  I didn't drain it again though, but I'll be doing that soon enough once I start going after it.

Compression test is up soon.  Since we're on the exact same page, any other thoughts you have?  I was going to go at the minimum amount of parts possible to get me up and back running.  (A few gaskets and the water pump)  I'd hate to drop hundreds extra on stuff that just isn't that bad.  POSSIBLY a new timing chain and crank sprocket.

PSA for anybody driving an 08-16 Mazda, or ford.  If you have a 3.5 or 3.7L V-6 with a timing chain, find out if you have an internal water pump.  If I hadn't stopped the car when I did, towed it instead of driving it home, and have the ability to work on it, I'd be fucked.  anything over 90k miles on the internal chain driven water pump should be changed.  DOUBLY SO if you have the single sprocket timing setup.  The newer one seem to have side by side sprockets resulting in what is essentially a double chain.

[Syonyk]

I'm not familiar with that engine, so no specific advice other than "It's silly to not replace other stuff in there while you're in there."  I'd rather spend a bit more and do the various bits and pieces exposed while I'm in there.

=========

Sorry, I forgot which forum I was on.  Have you considered leasing a brand new EV?  For the cost of the parts, you could get half a month or more lease time on a brand new EV, versus having to get your hands dirty and, like, fix an ancient, obsolete car that's clearly failure prone!  </s>

[lukebuz]

Not true.  Some cars have the water pump inside the timing covers, and if it leaks, it'll drain into the oil.

My bad.  I guess my wrench turning skills are a bit outdated.  I guess last car I did a water pump on was a 1991...

[gooki]

PSA for anybody driving an 08-16 Mazda, or ford.  If you have a 3.5 or 3.7L V-6 with a timing chain, find out if you have an internal water pump.  If I hadn't stopped the car when I did, towed it instead of driving it home, and have the ability to work on it, I'd be fucked.  anything over 90k miles on the internal chain driven water pump should be changed.  DOUBLY SO if you have the single sprocket timing setup.  The newer one seem to have side by side sprockets resulting in what is essentially a double chain.

My CX-9 engine is up to 240,000 kms. It's a hard call to do a preemptive repair as there's millions of these engines out there, and the repair cost is high. I just keep an eye on the engine temp.

There's a Mazda bulletin for this issue, all it involves is a visual inspection of the water pump weep hole. If there's excessive coolent crystalizing around the hole Mazda recommend a preemptive replacement. Seems a bit basic to me.

[jo552006]

To anybody who was watching this for personal reasons.  The car is now back on the road.  There doesn't seem to be any engine damage, but I guess we'll know for sure a few months from now.  The job sucked, but overall seemed to go well.

As for preemptive repairs, I guess to each their own.  Had I realized my water pump was internal despite having a timing chain, I'd have done it 20,000 miles ago but that's just me.  It was also MUCH cheaper not taking it to a garage or dealership for the work.  Though I did phone a friend who used to work at dealerships and he really helped a lot (he did most of the job TBH).  I don't know if I could have done it without him, but I definitely wouldn't have wanted to.

[gooki]

Great to hear it's back on the road.

[Model96]

Good to hear you were able to repair it fairly easily.
The water pumps on these are not exactly quality, they also lose their plastic impellers easily….