My step-daughter is driving our 2014 Mazda CX-9, and we had planned to sign it over to her this year. Unfortunately, it's had a bad year. The alternator died when it was 80 miles away, the transfer case let go in September, and just last week I found coolant in the oil. So the dreaded timing chain driven water pump has reared it's head. The last oil change was at 122k miles back in late September, and it's now at 126k, so we were pushing our luck driving it. But I just haven't had time to order parts and replace the water pump and all the "while you're in there" stuff. Well, now I get to make the time.
This is what came out when I removed the oil filter (the sump looked similar). FWICT, the coolant hasn't been in there more than a few weeks. The car was running fine when I noticed this. After draining the oil, there appears to be less than a quart of extra fluid, or about the entire reservoir. I've stripped the top of the engine, ordered a bunch of parts, and pulled one valve cover. Besides a few puddles of somewhat milky oil, the valve-train looks very clean. My plan is to clean up under the valve covers and pull the front cover to replace the water pump and timing chains/guides. I'll also do spark plugs, injectors and thermostat while the plenum is off. With luck, no long term damage was done to the bearings. Worst case, I buy a used engine and swap over the new parts to that. That's on the order of $3k to 4k, so fingers crossed.
My thoughts on returning this to service are to let the sump drain while I'm working on the engine and pour some cheap oil through the block to flush it and help clear the sump. When it's ready to start, it will get cheap oil/fresh filter and drive for 50 miles or so, then more oil changes until it comes out clean. Then I'll fill it with the good stuff and see what happens. Any other options I should consider? There might be some product that binds with the water to help clean out the block.
If this wasn't such a good car otherwise, I'd take it out and shoot it. What a stupid engine design.
02Pilot
PowerDork
12/4/22 9:55 p.m.
Sending off an oil sample to check for bearing material might be prudent before getting stuck in on all that work.
Change the oil twice after you get it running and ship it. You'll be fine.
It takes a loooong time for coolant to damage the bearings. I had a customer with a 3100 Malibu who couldn't afford to do the intake gaskets and put it off for two years. She was fine.
I had another who went longer and we ended up having to replace a few pushrods and rockers because the rockers' pushrod cups galled, as did the pushrod tips.
02Pilot said:
Sending off an oil sample to check for bearing material might be prudent before getting stuck in on all that work.
I saved the drain oil just in case. This may be a good idea for peace of mind and/or planning for the future demise of this engine.
In reply to Pete. (l33t FS) :
Thanks Pete.
I'm really kind of stunned how clean this engine is. I suppose while the spark plugs are out I should check the cylinders with a scope.
My wife ran a 3.4 Chevy with milkshake oil for an unknown period of time. I changed the lower intake gaskets and put it back on the road. That was about 100k miles.
150k later under my son's ownership, it did it again and my son changed the gaskets and put it back on the road. At a little over 300k it hit something harder than it was and went to the bone yard still running and driving.
By far one of the most durable vehicles I have ever owned. Other than maintenance items it only needed two sets of intake gaskets and an alternator in 300k miles.
Fix it and send it.
Even 2 rapid oil changes is probably overkill, probably just 1 rapid change will be fine. Milkshake doesn't tend to damage bearings.
Ugh, my wife has a 2014 CX-9 and I'm suddenly nervous lol (though hers has like 80k miles).....
In reply to irish44j (Forum Supporter) :
I had a customer with 275k on his Flex with the original water pump and timing chains. He had us do them for preventive maintenance.
There are -so- many engines out there with this setup it's funny that everyone dogpiles on this particular one. That is the price of popularity I suppose 
Nissan VQ engines are another common engine that uses this setup. So are Chrysler 2.7... okay bad example.
irish44j (Forum Supporter) said:
Ugh, my wife has a 2014 CX-9 and I'm suddenly nervous lol (though hers has like 80k miles).....
There's a weep hole in the water pump that exits just over the alternator that indicates when the inner seal of the two water pump seals has failed. Check that as an early indicator. Ours was dry, so I'm really curious how it failed. Another 2 quarts of coolant has drained through the sump, so it's a serious leak. I suspect the shaft seal failed. Now that the valve covers are off, it appears the timing chain is fairly slack, so maybe the timing chain tensioner has failed. My thought at this point is to replace the water pump and timing chain/guides every 120k miles for peace of mind. I'm replacing lots of stuff, and the total bill is under $1500.
Keep an eye on the inside of the oil filler cap. That was our first indication of trouble. Also, keep your coolant fresh and cooling system clean. That will help prevent early failures.
My 1979 Trans Am has a hole in the hood (because shaker) and it wasn't properly sealed and the drain was broken, meaning water sat in the crankcase a lot. I have drained chunky milkshake oil out of the thing at least 10 times and it's fine. I think you'll be OK. Good luck with the fix!
For various reasons (death in the family, COVID, and Christmas, in that order) I just now got around to turning the wrenches around on this repair. Nothing was terribly hard, although removing the power steering pump from the firewall side of the engine was not enjoyable. I decided to replace the power steering pump and hoses because I never want to see them again. Here's where it's at now with the new water pump and timing chain/guides in place.
The water pump was indeed shot. It wobbled around quite badly and I am surprised it didn't lock up sooner. Right now I'm waiting on the cam sprocket bolts which are torque-to-yield and should be replaced. In the mean time I'm going to clean up the covers and check the valve clearances because this engine uses shims.
...Now is probably not the best time to tell you that it is possible to change the pump without pulling the sprockets. Assuming that you weren't changing the chains.
It takes some special bent wrenches (they are allegedly brake bleeder wrenches, but they are way more useful than that) to get at the guide bolts that are behind the sprockets, but it is juuuuust doable. The guides don't come off, just get pulled back enough that you can slide the pump out from behind them.
It is downright creepy how these engines are always clean inside, too. If they weren't all attached to Ford transmissions I think they'd be great swap candidates.
In reply to Pete. (l33t FS) :
I wanted to replace the timing chains anyway, but I'd bet they would make it another 100k miles. One of the cam chain tensioners felt really rough, so not a bad call. The factory manual says you can remove the lower guide bolt and swing the guide out of the way, but this guide is on a pin, not held down with a bolt.
I like this engine too. It's been great up until now, and I'm just considering this an issue of deferred maintenance. Given the condition of this water pump, I'd consider this an every 100k job.
Just how critical is replacing the cam sprocket bolts? I'm going to wait for the new ones unless they end up taking months to arrive.
Pete. (l33t FS) said:
...Now is probably not the best time to tell you that it is possible to change the pump without pulling the sprockets. Assuming that you weren't changing the chains.
It takes some special bent wrenches (they are allegedly brake bleeder wrenches, but they are way more useful than that) to get at the guide bolts that are behind the sprockets, but it is juuuuust doable. The guides don't come off, just get pulled back enough that you can slide the pump out from behind them.
It is downright creepy how these engines are always clean inside, too. If they weren't all attached to Ford transmissions I think they'd be great swap candidates.
They are great swap candidates....I have one in the '66. The longblock weighs it at 280lbs, they make 300HP+, get 30mpg, etc. Just ignore the fact that they are as wide and as tall as a 351W. As for the transmissions...nothing wrong with Ford transmissions. The MT82 gets a bad rap because of the poorly designed remote shifter setup and a dual mass flywheel...once you adress those issues there is nothing wrong with the transmission....but the MT82 like all 6 speed transmissions is a gimmick. It has a whole 4 usable gears under normal driving, you would be better off with a 4 speed toploader, or a T5 if you insist on a highway gear. When doing swaps you don't have to stick with the transmission of the car it came out of after all.
In reply to Wicked93gs :
Those are all manuals though, not automatics.
Pete. (l33t FS) said:
In reply to Wicked93gs :
Those are all manuals though, not automatics.
Whats an automatic? I don't drive slushboxes! Seriously though, I really don't drive automatics, I find all of them unreliable compared to manual transmissions...and no fun to drive as well. The only reliable auto I have ever owned was an old TH350 in a '75 Trans-Am...that trans had to be almost as reliable as the manual transmissions I have had since.
In reply to Wicked93gs :
The thing with manual transmissions is you have to lift to shift, which makes them painfully slow in the city. And they are EXPENSIVE. Just a flywheel for a swap might be $1000, let alone the transmission My experience suggests that manual transmissions are maintenance items, so better choose one that is easily and cheaply sourced...
In reply to Pete. (l33t FS) :
What? Maintenance items? Maybe if you beat them into the ground that might be true...but I am approaching 350k on the MTX in my Mazda 6 with only one single clutch change on it(and one slave cylinder and one MC replacement) no grinds, no issues at all. I don't remember the last manual transmission that hasn't lasted me at least 150k miles.....as a matter of fact, I have NEVER had a failure out of manual transmission aside from clutch wear. The opposite is true for the auto transmissions I have owned...aside from that TH350, every singe one has failed...usually before 150k, never any later than 200k. This is the same type of driving on both(no racing aside from the occasional drag strip visit, but occasionally a spirited sprint here and there). As for city driving....glad I don't live in the city any more...but the few times I go to the city, I don't find shifting makes it slow to accelerate, but traffic is a nightmare with a 3rd pedal. I have never in my life paid $1000 for a flywheel, custom swap or not, there is almost always some bolt-up flywheel available you can find used for $50 and get resurfaced, even if some research is required to find what will fit inside a given bellhousing and what diameter of clutch disc will fit on it.
I will admit that there are plenty of manual transmissions that are expensive though(R154, T56, etc) but usually you can find an alternative that will work just as well for what you want(MA-5, T5, etc) if you aren't dead set on having some vanity feature like 2 overdrive gears.
If you like like your tractors engine that makes tons of low end torque and drag racing is your thing....then yes, finding a manual transmission that stands up to that abuse leaves you with fewer options...but they are still out there, Toploader T4, T56, etc(heck, the MA-5 will work for that as well).
I guess it comes down to driving habits. I don't beat my transmissions to death and I find curves a whole lot more fun than accelerating from a dead stop, and I don't live in cities any more(nor would I ever willingly do so again) so the fewer parts in the trans, the more reliable it is for me.
Yup, everybody has their thing. I am usually in 3rd or 4th gear by the time I cross an intersection from a stop, and that is awful slow, but less antisocial than revving out past 3k all the time.
In reply to Pete. (l33t FS) :
I guess that would depend on how obnoxious the exhaust note is. 3k is pretty standard for shifting a MTX under normal driving conditions. Normal driving conditions you really don't need to be hammering the car anyway, I think sometimes people forget this when every car out there is sold on 0-60 times...as if those times even matter anywhere that you aren't actively drag racing. As long as your aren't as slow as a truck it really doesn't make much difference in traffic anyway. More often than not someone in front of you is accelerating a lot slower than you are anyway. If I am hitting 3rd by the time I cross an intersection I have a terrible 1st and 2nd gear ratio or a rear end/final drive ratio that is too low to belong on the street.
JoeTR6 said:
Just how critical is replacing the cam sprocket bolts? I'm going to wait for the new ones unless they end up taking months to arrive.
The only way to really know is ask sloppy mechanics, but a torque to yield that holds on a cam gear seems like a play-it-safe situation.
Paul_VR6 (Forum Supporter) said:
JoeTR6 said:
Just how critical is replacing the cam sprocket bolts? I'm going to wait for the new ones unless they end up taking months to arrive.
The only way to really know is ask sloppy mechanics, but a torque to yield that holds on a cam gear seems like a play-it-safe situation.
Yeah, that's what I'm thinking. It's odd that the full timing chain replacement kit only came with 2 new bolts. Since this kit comes with all new guides and small cam sprockets, you definitely need to pull all four cam sprockets. While I should have been sleeping last night, I was thinking about using the two new bolts I have on the VVT sprockets (which are driven by the main chain) and the used bolts on the smaller sprockets. But that's the sort of desperate stuff you should only consider while half awake.
This is the epilogue on this story. I finally got the parts shipment held up by the stretch bolts about two weeks ago. They went in, the covers went on, and everything went smoothly until I hit the power steering belt. Whoever thought up a belt with no adjuster should be shot, particularly when there's poor access to the pulleys. Here's what I did.
Turning the crank pulled the belt around the power steering pump pulley and got it on, but it took me a few iterations to figure out the right combination of the Gates tool and zip ties, plus a small modification to the tool.
So with that done, the wiring harness was hooked up and it purred back into life. With 70 miles since then, it's running well. I'll change the oil at 100 miles and return it to the daughter. It's a good thing this is a 100k mile service, because I'm not sure I want to do it again anytime soon.
I actually like the belts with no adjuster and find them a lot easier to put on without a tensioner...but then, my engine is also RWD where I have access to the pulleys. On the RWD 3.7L the only belt that is like that though is the AC belt.
