2012 Mazda CX-7 - 2.5 NA questions

My father in law was driving and the car on I-95 and it overheated. He basically overheated the living hell out of it until he pulled off the highway and  the car shut itself at a light. Would not start anymore and got towed to the house. 

This is my mother in law's car and so I got called. I try to start and there is very little compression. Pull plugs and there is oily water in the cylinders. Mazda quoted $2900 for a head gasket change without seeing it. 

I told them given the car was bought new and has 50k miles its worth fixing. I feel like its going to sit for a while as I was clear that if they find more damage the price will go up fast. 

I don't feel like working on that car, but given they do help us with our kids and I am their car guy I need to get involved here. So a few questions with those that have knowledge of these engines:

1. Chain or t-belt?
2. Does it have some sort of VVTi/VTEC or complicated cam movement that requires specific tools?
3. Aluminum or iron block?

I keep wondering what the chances are he cooked the piston rings or anything else. 

Thanks. 

Timing chain

Yes, variable intake timing, special tools are easily made (I use a piece of flat stock to keep the cams in time)

aluminum all around. 
 

Your best bet is just to pick up another engine.  The long block in that is the same MZR/Duratec 2.5 that is is most Mazda and Ford products of the era: 3, 5, 6, Fusion, Escape, etc.  If you get a Ford version you need to do basically a long block swap using all the Mazda accessories/oil pan/crank pulley/manifolds.  The engines are everywhere and dirt cheap.  

From 2010 - 2012 the base Mazda CX-7 got the NA 2.5L.  I think this is the same 2.5L in the boxy Ford Escape from 2010-2012 as well as the Ford Fusion starting in 2010.  The Mazda5 starting in 2012 used the engine too.  Probably others too.

My point being, this is a plentiful engine and a replacement, JY engine might be cheaper...maybe.  

The site car-part.com may be helpful for finding an engine in your area

EDIT: beat by Sonic!

Just replace the engine.  The bottom end is damaged if it has low compression, especially if he drove it until it stalled.

If you forge ahead, there are no keyways on the cam or crank, so you need special tools.  Special tools being a file with some shims to line up the cams to the head, a special length bolt for a crank stopper (plans available online), and you will need to make a pin to line up the harmonic damper when installing it, because of course they put the crank trigger wheel on a part that is not keyed to the crank.

All internal bolts are use once and throw away.

If this is the same engine as in the Fusion and not after the Duratec/Skyactiv engineering split, these engines never fail and Ford made a bazillion of them, and it is easy to find them in yards with warranty for $300.

Thanks for all the input. 

I checked car-part and it looks like $900 is what the engines go for. I might be able to go get one at a junkyard but I am not sure I want to pull two engines, so $900 might not be a bad option if I am still saving them $1500 after we buy anything else that might be needed. 

I just spoke to my FIL and he said Hyundai offered $2k for the car as is of he trades it in for a new car. He is considering this and will go look at their small SUVs today. 

Will let you guys know what happens and maybe start asking questions if I decide to swap the engine. 

In reply to Slippery :

At 50k miles, this is a $10-$15k car in this market! 

In reply to John Welsh :

Seriously. Even if Hyundai gives him $2k for it, he still has to spend what, at least low 20s.

If he wants to sell it, someone here could give him $2001 and do the engine swap. Then either drive it or sell it for a nice profit.

Fix it. The used car market is so strong and the NA versions of that vehicle are pretty bulletproof. We bought ours new and are sitting at about 145k right now. Not a lick of trouble. 

Might be getting fixed after all. 

They offered him $500 at Honda and they quoted an insane price for an HR-V  ... he is going to Kia tomorrow I guess but he is guving up on that thought. 

Just to close this out. Car got fixed. Found an engine with 60k miles for $2200 and labor was $1060. 

I told him to go for it as he wasn't going to find a replacement car for that much. The replacement engine was most likely overpriced but it came with a warranty and I could not find many alternatives. 

Well done.  Sorry it had to be this way but...

In his possession he had a non running Mazda with a value somewhere between $0, $500, and $2,000.  He added $3,260 to the car.  

He could not have bought a nicer car for $3,260. 
He could not have bought a nicer car for $3,260 +$500 = $3,760. 
He probably couldn't even bought a nicer car for $3,260 + $2,000 = $5,260

Now running, that is still likely a $10-$15k car, in this market.