CX-9 Engine Replacement Compatibility

[vadimkru]

Hello,

I have 2018 CX-9 that has the cracked head with coolant leak (confirmed by dealer). The warranty work was denied due to car having salvaged title.

I’m looking to buy a replacement engine from 2023 CX-9. Do you know if it is a direct replacement?

I know that I have to replace with an engine that is at least 2020+ that has the fixed head design.

 

[N7turbo]

Technically yes but you'll want the 2023 ECU as well. What I don't know is, does that affect any other system.

 

[1010]

Hello,

I have 2018 CX-9 that has the cracked head with coolant leak (confirmed by dealer). The warranty work was denied due to car having salvaged title.

I’m looking to buy a replacement engine from 2023 CX-9. Do you know if it is a direct replacement?

I know that I have to replace with an engine that is at least 2020+ that has the fixed head design.

So why would you replace the whole engine? Just buy the cylinder head. I understand you are not in the USA, but even with shipping and customs fees, it will still be cheaper. I contacted Mazda USA, and they provided me with the part number for the cylinder head. I specifically asked for the updated one, from after 2021. Here is the part number for the updated cylinder head.Look it up on American websites; some of them have promotions now where you can buy it for $650.
PYY1-10-SJ0C

 

[N7turbo]

So why would you replace the whole engine? Just buy the cylinder head. I understand you are not in the USA, but even with shipping and customs fees, it will still be cheaper. I contacted Mazda USA, and they provided me with the part number for the cylinder head. I specifically asked for the updated one, from after 2021. Here is the part number for the updated cylinder head.Look it up on American websites; some of them have promotions now where you can buy it for $650.
PYY1-10-SJ0C

That is certainly preferred to an engine swap which is a huge job--but I would recommend the complete assembly rather than a bare head.

 

[1010]

Это, конечно, предпочтительнее замены двигателя, которая требует огромных усилий, но я бы рекомендовал полную сборку, а не голую головку.

«Ну, это зависит от того, в какой стране вы это делаете. В моей стране, например, замена головки блока цилиндров стоит около 500 долларов. Автор может быть не в США.
Целый двигатель может обойтись в очень большую сумму
С уважением.

 

[N7turbo]

"Well, it depends on which country you do it in. In my country, for example, replacing a cylinder head costs about $500. The author may not be in the USA. Respectfully.

Around here (Midwest USA) you will spend a lot more than $500 to replace a cylinder head.

But what I'm referring to is there are two part numbers--one for the head only and one with the valves etc installed. It saves on labor and eliminates errors. I don't have it but I believe @yrwei52 does.

 

[vadimkru]

I was able to find a complete engine (without turbo, AC, alternator) for $2K from 2023 cx-9 with 22k miles and according to a local shop - they can swap it for $1K and it is a lot less labor than rebuilding the old one (you will need to drop the engine for head swap anyway).

 

[1010]

I was able to find a complete engine (without turbo, AC, alternator) for $2K from 2023 cx-9 with 22k miles and according to a local shop - they can swap it for $1K and it is a lot less labor than rebuilding the old one.

Well, of course, that changes the situation. This is a very good deal

 

[N7turbo]

I was able to find a complete engine (without turbo, AC, alternator) for $2K from 2023 cx-9 with 22k miles and according to a local shop - they can swap it for $1K and it is a lot less labor than rebuilding the old one (you will need to drop the engine for head swap anyway).

There is no reason the engine needs to be removed for a head swap.

And I simply don't believe that a cylinder head with valve assembly is more labor than a complete engine swap, especially considering you still have to install extra parts like the turbo, etc.

That is a good deal on the engine, but there is something wrong with the pricing of this job.

 

[1010]

And by the way, why would anyone need to remove the entire engine to replace the cylinder head? The manual seems to say that it's not necessary to remove the whole engine.
Yes, it's great that you basically get a completely new engine for a small price, which is certainly a plus. But replacing the whole engine turns out to be much more expensive than replacing the cylinder head

 

[N7turbo]

Rarely does an engine need to come out of a car. Usually that happens when you need to do "bottom end" work—things involving the engine block, crankshaft, rods, or pistons.

But for "top end" work, the engine stays in the car.

 

[sm1ke]

This might clear it up a bit more. In the documentation for CSP11, they list the labor hours for each option. Specifically for the CX-9 AWD, cylinder head replacement is 11.3 labor hours, plus 0.8 or 1.3 labor hours for a front wheel alignment. Engine replacement is listed at 10.9 labor hours.

I don't know if the engine needs to be dropped for the cylinder head replacement as the instructions require logging in to MGSS. But the above at least shows that the head replacement, for whatever reason, does require more labor hours compared to an engine replacement.

 

[N7turbo]

This might clear it up a bit more. In the documentation for CSP11, they list the labor hours for each option. Specifically for the CX-9 AWD, cylinder head replacement is 11.3 labor hours, plus 0.8 or 1.3 labor hours for a front wheel alignment. Engine replacement is listed at 10.9 labor hours.

I don't know if the engine needs to be dropped for the cylinder head replacement as the instructions require logging in to MGSS. But the above at least shows that the head replacement, for whatever reason, does require more labor hours compared to an engine replacement.

But is that assuming that the head is not a complete assembly? I think that can make a big difference.

 

[sm1ke]

But is that assuming that the head is not a complete assembly? I think that can make a big difference.

I don't think it's a complete assembly. From TSB 01-002/23, we know that a cylinder head replacement includes reusing the water outlet, fuel distributor, fuel injectors, OCV oil filter, rocker arms, HLA, CMP sensors and engine hanger brackets. That probably contributes a good amount of labor to the total.

Replacing the cylinder head as a full assembly should mean that the overall part cost for cylinder head replacement would increase, but labor hours would be lower. It would still be much cheaper than replacing the whole engine. But the whole point is that for this specific repair, where certain parts are to be reused, the cylinder head replacement does take longer than an engine replacement.