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Old 01-08-2020, 08:12 AM
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Paul Waterloo
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Default Bore Scoring 101

I have posted before that my daughter's 2013 Hyundai Elantra has a TERRIBLE tick in the engine. Started with less than 50K miles. The car is a rebuilt title, so no factory warranty.

I just bought a used engine for $500 so I could rebuild it and then put it in her car. Parts are cheap! An oversized piston and ring kit for the four cylinders is $80! I figure for about $1200 I'll complete the rebuild, which includes the $500 engine purchase and machine shop services to bore the cylinders. No nickies for this engine.

Anyways, took it apart last night and Jake is right, if you can see scoring at the top of the cylinders from the spark plug hole (I actually inspected the engine before I bought it with a borescope), it's going to be way worse below.

A short video.....need to work on my video skills.....


And going back to the original video with the debris in the pan from her engine, I'm sure the scoring is TERRIBLE in that engine. She went to college in Minnesota, where it has freezing temps. People in Canada complained about these engines first.

Old 01-08-2020, 08:42 AM
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Mike Murphy
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Wow, all 4 cylinders.
Old 01-08-2020, 08:51 AM
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GarrettSR5
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I bet that Hyundai would have run another 500k
Old 01-08-2020, 09:22 AM
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NuttyProfessor
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Originally Posted by GarrettSR5
I bet that Hyundai would have run another 500k
I know you're being a bit facetious, but I would predict these pistons would have cracked or the shedding of metal would have caused severe damage that would lead to engine failure similar to what we've seen in the M96. This problem is turning into a pandemic.
Old 01-08-2020, 09:44 AM
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billh1963
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Originally Posted by NuttyProfessor
I know you're being a bit facetious, but I would predict these pistons would have cracked or the shedding of metal would have caused severe damage that would lead to engine failure similar to what we've seen in the M96. This problem is turning into a pandemic.
One of those unintended consequences of cold starting and direct fuel injection? Maybe carbs or TBI was better?

Old 01-08-2020, 09:50 AM
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NuttyProfessor
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Originally Posted by billh1963
One of those unintended consequences of cold starting and direct fuel injection? Maybe carbs or TBI was better?
haha... yea, sometimes the industry solves one problem and creates more as a result. Have you seen where manufactures are putting pairs of injectors on DI cars? One for combustion and the other to wash the valves.

Old 01-08-2020, 09:55 AM
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danielcooper9
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Scoring on the Elantra was a factory problem. I don't remember the specific details but something about metal debris from manufacturing not being cleaned sufficiently. Hyundai replaced quite a few motors under warranty for this issue.
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Old 01-08-2020, 10:45 AM
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Nice work and nice project to tackle! Great job!
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Old 01-08-2020, 01:18 PM
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hatchetf15
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Originally Posted by danielcooper9
Scoring on the Elantra was a factory problem. I don't remember the specific details but something about metal debris from manufacturing not being cleaned sufficiently. Hyundai replaced quite a few motors under warranty for this issue.
This correlates to what LN recently put out about ensuring the fresh cylinders and pistons are absolutely clean before assembly. Lots of tiny particulates that can get trapped and score bores from new, first start. Good project and thanks for sharing, Paul.
Old 01-08-2020, 03:55 PM
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Argeo
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I've given up being too concerned about the big things. What's next? I've already done two IMS bearings. My only change on this matter is I am not running in cold weather now (under 40F). I put away for the winter anyhow due to salt so not really an issue.

Now seeing plenty of 996/Boxster's on the road, I bet the majority have not a clue about any of this. Envy them sometimes.

I will continue to do the maintenance stuff such as water pump/coolant tank/AOS to allude issues when driving but the rest is not in my hands without sending a lot more money. I love the car but not enough to justify spending what I paid for it.

Old 01-08-2020, 03:59 PM
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5CHN3LL
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Sorry, Paul - can't help myself. Here's some Hyundai pr0n from the past (my torque-steer project before I picked up my 986)...



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Old 01-08-2020, 04:02 PM
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motoo344
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Originally Posted by danielcooper9
Scoring on the Elantra was a factory problem. I don't remember the specific details but something about metal debris from manufacturing not being cleaned sufficiently. Hyundai replaced quite a few motors under warranty for this issue.

I think I remember seeing a post on Reddit where someone worked at a dealership and they just had Hyundai crate engines all over the place because of this issue.
Old 01-08-2020, 09:49 PM
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Flat6 Innovations
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Bore scoring is attacking modern engines across the board. I have been consulting with others like us that deal with domestic, and Asian engines who are just starting to see this.

Old 01-10-2020, 01:02 AM
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pdxmotorhead
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GM 4&6 Cyl eco-tec's, Ford Eco Boost, Fiat's, I've heard the new Alpha's are already seeing too many engine out services..
Honda is still dodging it on some engines with AL blocks and steel sleeves.
The ones without bore scoring are having piston skirt separation issues ...

DI diesels also..

Technology is not always your friend. LOL




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