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Discussion Starter · #23 ·
But this is after adding fresh fuel to the tank so I guess I should have thought about that first, it would now smell ok.
also is the noise getting any better less noisy fading or getting worse staying the same?
You were right, it was messy running the engine with the valve cover off.

I didnt leave it on for very long, but at least I was able to confirm the oil was not blocked from getting to the rockers.

The noise is coming from the valvetrain, intake side. If I can, and this will be risky, but if I can, I'm going to raise the pistons so that the valves cannot fall, then remove the retainers. Then lower the pistons so that my boroscope can see on top of the valves.

One more thing I forgot to mention. It sort of sounded like something fell after a started the car the second time after the issue started.
 

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Discussion Starter · #25 · (Edited)
Me again how long have you run the engine since the 'noise' started?
Also have you done a compression test yet?
I've not run it for more than 5 seconds at a time. The knocking turns into a grinding metal sound that you heard in the video in that span.

i recorded the cam lobes moving the valves up and down at 240fps, so, 8x slower when played back at 30 fps, and then on top of that I used a nice video editior with a AI powered slow motion effect to make it 9x slower than that.

Even at 72x slower than normal, there does not appear to be an obvious source of the sound, even though it is clearly coming from the 3rd cylinder intake.

I haven't done the compression test yet but that's just because I haven't been able to get to an auto parts store to rent the kit.
 

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Discussion Starter · #26 ·
@EvilChuckie666 Actually the rockers center lobe appear to be pushing the smaller 2 along with it. I'll investigave in a minuite. Would a partially stuck VTEC be the issue?

And now that I say that I know of only one thing that I did different than normal before the event

I got gas.
Then, I was on a wide, open, pretty highway, and decided to gun it and hit VTEC for the first time since I did my transmission rebuild a couple of months ago. It was breif. Like, just a couple seconds, only took her up to like 85, then within 10 seconds I pulled over at another gas station because I forgot cigarettes.

Then I started my car, drove for about 15 seconds and the car stalled after making the grinding noises.
 

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@EvilChuckie666 Actually the rockers center lobe appear to be pushing the smaller 2 along with it. I'll investigave in a minuite. Would a partially stuck VTEC be the issue?

And now that I say that I know of only one thing that I did different than normal before the event

I got gas.
Then, I was on a wide, open, pretty highway, and decided to gun it and hit VTEC for the first time since I did my transmission rebuild a couple of months ago. It was breif. Like, just a couple seconds, only took her up to like 85, then within 10 seconds I pulled over at another gas station because I forgot cigarettes.

Then I started my car, drove for about 15 seconds and the car stalled after making the grinding noises.
Hmmmm, could be the VTEC? but I would have thought that it would be obvious if there as an issue with it, and it would affect all cylinders equally? i'm sure you have looked/checked cylinder 3's rocker/valve and cant see anything?
 

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Discussion Starter · #29 · (Edited)

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I've heard of people putting "rope" into the cylinder to keep the valves up when replacing valve seals, just don't rotate the crank or drop the end in while doing so.

Maybe inspect the lost motion assembly and valve springs in that cylinder. It looks/sounds like it's only on cam lobe contact.
 

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Looking at the slow mo video, that's the vtec cam engaged. Seems like you have vtec when not wanted, as you've stated above. If all the other cylinders are not acting the same, the issue is with the slider pin between the rocker arms on that cylinder. Compare that area v's the adjacent cylinders for differences.
 

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Discussion Starter · #35 ·
Looking at the slow mo video, that's the vtec cam engaged. Seems like you have vtec when not wanted, as you've stated above. If all the other cylinders are not acting the same, the issue is with the slider pin between the rocker arms on that cylinder. Compare that area v's the adjacent cylinders for differences.
On it.
 

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Not really, it is oil pressure that forces the slider pins in the rockers.

Taking the rockers out is a meaty job, Cam belt off, cams out and then sliding out the mounting rod.

If it is one of the rocker assembly's locked in vtec, I'd be putting a lot of effort to persuade it to free off before taking everything apart.
 

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Discussion Starter · #39 ·
Not really, it is oil pressure that forces the slider pins in the rockers.

Taking the rockers out is a meaty job, Cam belt off, cams out and then sliding out the mounting rod.

If it is one of the rocker assembly's locked in vtec, I'd be putting a lot of effort to persuade it to free off before taking everything apart.
Yeah. Now that I think about it, this was the first time I used VTEC since I put these rockers into my new cylinder head from my old one.

I pretty much put all those pins back in drenched in assembly lube, and the rockers and pins never saw a water based cleaner so rust isn't the problem, so I'm not sure why they would become stuck.

As I was writing this, I went to the car and started mashing on the rockers and it dawned on me to mash on the Vtec rockers, too.

Unfortunately, the vtec rockers moved freely.

Knowing the vtec was disengaged, I unplugged the pressure switch and solenoid and turned on the car.

Good news, the awful grind went away after just letting it do its thing. It was hard to get the car started and to keep it running. Almost as if I pulled the plug on my fast idle.

Bad news, the tapping noise persists. Maye it is rod knock after all.

Will do the compression test as soon as I can get to the tool.

Were there any thoughts on the air escaping out of the third spark hole?
 

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Discussion Starter · #40 · (Edited)
@Vtecmec @EvilChuckie666 @Wing8806

Uh. This cannot have anything to do with anything can it?


A few other metrics I read before shutting to motor off was
a vacuum of -6
Engine rpms at 580

It's almost as if the ECU is never told to quit lowering everything as the temperature rises above operating temp...

Also, I made this compression tester. See any flaws before I try it out?
 

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