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Compare the deck design of the ford 2.3T, VW/Audi 2.0t, BMW N20 2.0t, and you can see that the Ford has a TERRIBLE design for high boost situations.

Ford 2.3l



VAG 2.0t



BMW N20, this is much closer to the Ford, but at least it still has stiffness added by connecting cylinders 1 and 4 to the block walls.

 

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I don't know how Canada works, but in the US, there's kind of no such thing as "really cheap fuel" since everything is so tightly regulated and there's only a handful of refiners that even make fuel in the first place. It's not like there's a discount refinery behind Walmart cranking out sub-par gasoline that doesn't actually meet standards.
Working in the diesel industry, I see people using their uncles marked gas from his farm that he's had in a holding tank for six months all the time. It almost always ends in disaster on a common rail system. That stuff is meant for 30 year old tractors.

Not only that, tuners have proven the motor is safe WAY past that. Let's face it, that 2.3L is a flop.
Well yeah, that's what headroom is :)
 

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Head gasket wear rate/movement.

It really seems like the open deck design of that motor is really not a good idea for high power operation.
Ding ding ding.

For everyone wondering why it took Ford so long to address the issue, or suggesting that Ford should just change out the gasket material.... Here's why the issue wasn't so simple.
 

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Could someone explain the design defect to the less mechanically inclined?

Looking at the photos one page back the Ford block has a strange empty space around each piston portion. Is this lack of rigidity causing the Ford pistons to move and wear away the wall lining?
 

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Could someone explain the design defect to the less mechanically inclined?

Looking at the photos one page back the Ford block has a strange empty space around each piston portion. Is this lack of rigidity causing the Ford pistons to move and wear away the wall lining?
The Focus RS block is an open deck design, which means the area surrounding the cylinders is open to the mating face of the block. The benefit of an open deck design is that easy to cast (low cost) since you don't have blind coring, and it can improve cooling. The downside is that an open deck block is generally less rigid than a semi-open or closed-deck block. This lack of rigidity can cause movement or flex of the cylinder relative to the head gasket. That relative movement, even if small, can cause fretting or wear of the gasket. Once worn, it can cause the head gasket to leak.

This article does a good job summarizing open vs. semi-closed vs. closed deck blocks:
http://www.enginelabs.com/news/supporting-your-cylinders-open-semi-closed-or-closed-deck/
 

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Could someone explain the design defect to the less mechanically inclined?

Looking at the photos one page back the Ford block has a strange empty space around each piston portion. Is this lack of rigidity causing the Ford pistons to move and wear away the wall lining?
The pistons themselves don't move, but if you mean cylinders, you're basically correct. Because there is less mass of material there, you are naturally going to get higher temps in the metal, more deformation, more movement. They design the block that way for a bunch of reasons, less weight, less material means less cost, more cooling system capacity, but there is a reason why most high performance applications use a closed-deck block, you need the rigidity there.
 

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Could someone explain the design defect to the less mechanically inclined?

Looking at the photos one page back the Ford block has a strange empty space around each piston portion. Is this lack of rigidity causing the Ford pistons to move and wear away the wall lining?
Take a coke can and hold one end and twist the other, you’ll see the surface deform. It’s the same principle except much smaller movement for an engine, the head and block mating surface is moving ever so slightly under high torque loads and wearing the head gasket in the critical areas shown in that picture above. An open deck block allows more movement than closed deck, but like other people have said they have reasons for using that design.


Sent from my iPhone using Tapatalk Pro
 

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I had no idea Ford went with a fully open deck block. What's Honda doing for their Civic Type-R? A quick search says the turbo versions are the K20C1, 2, and 3 as opposed to the more famous normally aspirated versions which are K20A, B, and Z for example. Does anyone know if the K20C in the new Civic Type-R is also open deck like the rest of the K-series engines?
 

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Is it purely an under high boost issue, or maybe something to do with warm up (metal expansion) and boost?
The engineering behind warm up expansion can be quite complicated too.
I saw a 3 rotor Mazda build video a while back on YT that showed the two piece crank (e-shaft) and floating mount of third rotor housing.
I was blown away...it was like a normal two rotor engine with a floating third rotor added- all because the hero sandwich design of a rotor engine had way too many heat expansion issues if hard mounted.
 

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Road and Track has a different theory:

http://www.roadandtrack.com/car-cul...e/a14510137/ford-focus-rs-head-gasket-issues/

Road and Track Magazine said:
Why the Ford Focus RS Is Having Head Gasket Issues
After crawling through forums, patents, designs, and service information, we think we've found the cause of the Focus RS's issues.

BY BOZI TATAREVIC
DEC 28, 2017


The Ford Focus RS is America's first RS and the most powerful version of the hatch that has ever been offered. Enthusiasts who wanted an RS for years but could never get one snatched the car up at the first opportunity. Some of those buyers just wanted a quick daily driver, while others took them right to the track. But, like other first year performance cars, there were issues that popped up.

The most notable issue shared in owners groups and on forums is blown head gaskets. While there has been some speculation on the underlying issues, there hasn’t been an official answer from Ford. We dug into Ford's service information and patents to find out why so many of these cars have blown head gaskets.

One of many threads on the FocusRS.org forums links to a spreadsheet that currently lists 48 cars with the problem. They vary from completely stock to heavily modified, but the majority of them appear to be early builds from April to July of 2016, with a few later builds sprinkled in towards the end. The issue usually presents itself with an engine that starts to run rough or when white smoke appears out of the exhaust, caused by coolant entering the combustion chamber.

Many theories on the root cause have popped up but it may all come down to an incorrectly delivered gasket. Many Focus RS owners have posted pictures of their failed head gaskets and the design appears to match the gaskets found on the Mustang 2.3L EcoBoost. While the two engines share many components and specifications, the cooling passages in the RS are different from those found in the Mustang.

The Mustang uses a small v-shaped passage cut into the block between the cylinders in order to transfer coolant across, as shown in the image above. There are two connected holes in the gasket which can accept coolant and transfer it all the way to the edge, at which point it can flow into the water jacket. These holes can be seen in the image below, which was pulled from Ford’s online service information website.

The block in the Focus RS is slightly different as it does not have this passage cut into the cylinder block. Instead, the coolant is routed through a passage that is drilled below the deck surface. This type of design only requires one hole on top to connect it to the cylinder head. That's because the other hole comes in from the side and below the deck. Ford has published a patent on this design. It explains that coolant enters adjacent to the block (132 on the diagram) and exits from the top of the deck (178 on the diagram).

Moving one of the coolant entry points from the top of the deck to the side and skipping the v-groove necessitates a change in the head gasket as the second hole and passage in-between is no longer required. Removing the second hole and the bridge in the gasket prevents coolant from seeping into the area between the fire rings where the v-shaped groove would exist on the Mustang block. Since there is no groove there to allow the coolant to circulate back into the block, it gets stuck in the passageway where it can boil and eventually damage the gasket. I've illustrated the area where the coolant would get trapped in red on the patent illustration below.

This head gasket change to one hole can be seen in the service information for the Focus RS and in images of the current Focus RS gasket online. It does not appear in any of the failed head gasket images. Ford even noted that the head gasket has been modified in their service information portal overview of the RS. This leads me to believe that Mustang head gaskets were incorrectly installed on some Focus RS engines.

One reason that the incorrect gaskets may have been installed is as a cost saving measure. However, I find it unlikely that Ford would cut costs there, particularly because the company took the time to redesign the coolant passages in the block. My theory is that both gaskets come from the same supplier and are made on the same lines since they are so similar. It is possible that a supplier incorrectly sent some Mustang gaskets for a run of Focus RSes and, since they physically fit on the block, it was never noticed that they were not correct.

Although we’ve seen a few stories on the subject and a lot of activity on the forums, I do not believe that the issue is widespread because Ford has not sent any type of bulletin or notification to their technicians at this time. We asked them to confirm our findings and let us know if there is a bulletin or recall on the way but they only shared the following statement:

Ford is aware that some 2016-17 Focus RS customers have experienced concerns with their engines, which may initially show white exhaust smoke and/or coolant consumption. We are working on a repair for all customers that will be available in the near future. In the meantime, if vehicles show these symptoms, customers should visit their dealer for an inspection and repair under warranty.

Ford seems to be taking care of the issue and is replacing the gasket, head, and even entire motors as necessary. According to some reports, Ford is a little behind as some cars have been sitting at dealers for weeks waiting on new head gaskets to arrive. Hopefully, it is able to share more information with us soon and confirm the misplaced gaskets so that owners can be at ease to enjoy their cars.
 

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^

Occam's razor (or Ockham's razor) is a principle from philosophy. Suppose there exist two explanations for an occurrence. In this case the simpler one is usually better. Another way of saying it is that the more assumptions you have to make, the more unlikely an explanation is.


The "using the wrong head-gasket because easy to get them mixed up at engine assembly plant" makes more sense than Ford intentionally making a media hyped car with an engine block that flexes too much under boost, causing a failed head-gasket.
 

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^

Occam's razor (or Ockham's razor) is a principle from philosophy. Suppose there exist two explanations for an occurrence. In this case the simpler one is usually better. Another way of saying it is that the more assumptions you have to make, the more unlikely an explanation is.


The "using the wrong head-gasket because easy to get them mixed up at engine assembly plant" makes more sense that Ford intentionally making a media hyped car with an engine block that flexes too much under boost, causing a failed head-gasket.

I tend to agree. It's some good work from MT to figure this out. If this is in fact the problem, certainly helps put some faith back into Ford. It's still a pretty bad screw up but at least it's not an engineering issue or simply trying to save a buck.
 

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Yep it is, and what'll probably happen is that all of the gaskets will have that extra passage from now on, assuming it isn't detrimental to the Mustang 2.3. Basically, every gasket will be the Focus RS gasket, that'll make the revision version essentially idiot-proof (don't quote me on that)
 
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