2016~2021 Engine coolant leak

Just wondering if anyone had this problem. I recently noticed I had some fluids leaking from the bottom of my 2016 Cx 9. I took it to a shop and they told me that the bolts holding the engine together had pulled out of the engine block because the engine block is made of aluminum which is a soft metal. The loosing of the bolts is allowing the coolant to leak outside of the engine, but thankfully not the internally. Has there been any service bulletin for this problem? The shop said they had to essentially take apart the told part of the engine and clean/check all the gaskets and then rethread the bolts. Estimated cost $2500-$3000.
 
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Mazda CX-9 Grand Touring 2016
Many engine blocks are aluminum these day with no problems. I'd suggest that you contact a dealership, speak with the service manager (not just any service writer) and ask them to put you into contact with the Mazda district rep. Also contact the Mazda corporate office for your country. In the U.S. that is Mazda North America, http://mazda.custhelp.com/app/ask
Their phone staff is off due to this virus.
 
I have to say that the story that shop is selling sounds like complete nonsense. I would promptly get the vehicle out of there and to a reputable shop that will pinpoint the leak and give you a rational estimate of the needed repairs.
 
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2010 CX-9 GT
I'd get a second opinion. I am skeptical that an honest mechanic would jump straight to stripped head bolts from a coolant leak. Most mechanics would diagnose a leak coming from the interface between the head and block as a blown head gasket. You have to remove the valve cover to even get to the head bolts, so unless they already started dismantling the engine I'd be highly suspicious at this point.

And if the head bolts actually pulled out of the block, don't try to re-use a head gasket. After spending $2500, saving $70 trying to reuse a gasket is not wise.
 
As of right now the only thing clear is that the gasket is leaking from the back of the engine. They said they won’t know if the bolts are stripped until they take off the headers. The 3rd party warranty sent an appraiser to look it over and verify what was wrong and he agreed. Right now it’s a waiting game for the appraiser to submit the paperwork.
 
Did you see this thread to see if there is any relationship to your situation? Seems like a very similar issue...

 
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2010 CX-9 GT
As of right now the only thing clear is that the gasket is leaking from the back of the engine. They said they won’t know if the bolts are stripped until they take off the headers. The 3rd party warranty sent an appraiser to look it over and verify what was wrong and he agreed. Right now it’s a waiting game for the appraiser to submit the paperwork.
So the diagnosis right now is a blown head gasket? From your description, it sounds like they were telling you that the exhaust manifold studs might be stripped during the removal process? This can happen if the studs seize in the block. Was this a "worst case" type of thing to prepare you for the potential of a $3000 bill? What is the repair estimate now?
 
So the diagnosis right now is a blown head gasket? From your description, it sounds like they were telling you that the exhaust manifold studs might be stripped during the removal process? This can happen if the studs seize in the block. Was this a "worst case" type of thing to prepare you for the potential of a $3000 bill? What is the repair estimate now?
Right now it’s 2500 to take It apart and repair the gasket. They said if the bolts are damaged and they have to rethread it will be closer to 3000. I asked about their warranty and they said 24 months or 24000 miles. So I’m pretty comfortable with that.
 
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2010 CX-9 GT
That estimate seems high for just replacing the gasket. This is an inline 4, one gasket, and it doesn't seem to have major access issues. I'd expect the price to be $1500 give or take.
 
Just an update, after more digging around the entire engine was replaced. Thank God I had that extended warranty as the job would have cost around ~$8000. I was hoping to get a brand new engine, but unfortunately the third party warranty company didn't want to pay for a new one. However the engine they found only had 29,000 miles on it, compared to my 80,000 miles. Also they looked over the engine, replaced all the gaskets and moved my new spark plugs from the old engine to the new one. Not too shabby.
 
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2010 CX-9 GT
That's 2 or 3 vehicles now with coolant leaks that required an engine replacement. I wonder if there was some sort of casting flaw in the blocks.
 
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2016 Mazda CX-9 GT
Just an update, after more digging around the entire engine was replaced. Thank God I had that extended warranty as the job would have cost around ~$8000. I was hoping to get a brand new engine, but unfortunately the third party warranty company didn't want to pay for a new one. However the engine they found only had 29,000 miles on it, compared to my 80,000 miles. Also they looked over the engine, replaced all the gaskets and moved my new spark plugs from the old engine to the new one. Not too shabby.
mchu123 What was your CX-9 build date?
 
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2010 CX-9 GT
My CX9 is a 2016
Did the repair shop provide a precise diagnosis of the problem? I'm interested to know why the only course of action was replacement of the engine.

Also, the build date is recorded on a plate inside the driver's door on the B pillar. The month and year of manufacture is listed there.
 
Did the repair shop provide a precise diagnosis of the problem? I'm interested to know why the only course of action was replacement of the engine.

Also, the build date is recorded on a plate inside the driver's door on the B pillar. The month and year of manufacture is listed there.
Oh that's good to know. I will check the plate when I get my car back from the the shop repairing the infotainment screen. As far as what else the shop diagnosed, I will check the forms they gave me when I get the car back.
 
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2007 Mazda CX-9 Touring
It was much cheaper for them to go with a low mileage engine. I can't believe the prices i saw on the internet for used engines for a 2016. They had one with only 7k miles for 2500. That's pretty good if you ask me. The first gens are more expensive with high miles.
 
I don't know the details, but the repair shop initially thought it was just the gasket and when they started taking the engine apart they recommended replacing the long engine block. It was also looked at by the extended warranty person, and we all know they try to get out of paying for anything, so it must have been a legitimate issue. The car was built 4/2016.
 
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2010 CX-9 GT
Replacing the long block would point to the head and block warping so much that they couldn't be machined flat without removing too much material. Or, there were cracks in the head/block.

Either way, that's troubling if it is what happened....
 
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2005 Mazda3
I don't know the details, but the repair shop initially thought it was just the gasket and when they started taking the engine apart they recommended replacing the long engine block. It was also looked at by the extended warranty person, and we all know they try to get out of paying for anything, so it must have been a legitimate issue. The car was built 4/2016.
Any updates on your situation? Did you get the block replaced?
 
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