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Need Help, Advice, Input - Knock After Harmonic Balancer Replacement

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Old Jan 19, 2019 | 03:02 PM
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Default Need Help, Advice, Input - Knock After Harmonic Balancer Replacement

My harmonic balancer failed about a month ago and I'm in the process of putting things back together.
While I was replacing the balancer it seemed a good idea to replace the timing sprockets, chain, add a timing chain dampener, oil pump and water pump.
I decided it would be a good idea to see if everything turns over and doesn't leak, so, this morning I started it up briefly.
The throttle body is bolted on and the water pump is in place. Cooling system is still drained and no hoses are connected to the water pump.
The 2 wires are connected to the throttle body. No other wiring or sensors are connected. Steering rack is still out.
I'm getting a knocking noise and can't figure out what it is. I've attached a link to a YouTube video that has the noise on it.
I primed the oil pump per instructions on the Melling website. Getting good oil pressure, 45-50 lbs, better than I've had before on the car.
The car has 194k miles.
Trying to figure out if the knocking is due to all of the accessories that are not connected or if it's an actual problem that I've created during assembly.
Friends that I've asked seem to be split. Some say to get it all back together and the noise will go away once the computers are getting all of their info and properly controlling the engine.
Other say to take it all back apart and check everything.
Any input is greatly appreciated.
Thanks in advance for any help.
https://www.youtube.com/watch?v=JGld...ature=youtu.be

Last edited by Zmeister; Jan 19, 2019 at 08:48 PM.
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Old Jan 19, 2019 | 03:32 PM
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This video is unavailable.

That's what I got when I clicked your link. If it's truly a "knock", no way I would put it back together and try again. Computers don't fix "knock". Maybe your oil pump o-ring is cut, not correctly installed, whatever and you aren't getting oil pressure. Okay, I re-read your post and you said you had good oil pressure? How long did you run it, and did the knock sound like it was low in the engine, or high?

Last edited by frodo84; Jan 19, 2019 at 03:34 PM.
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Old Jan 19, 2019 | 04:12 PM
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Thanks for the reply Frodo.
We're having a hard time telling where the sound is coming from. In the engine is all we've been able to come up with so far. To me it sounds like more from the front, but, my buddy who's been helping me says that to him it sounds more from the rear.
The o-ring seemed to go in very nicely. I was worried based on problems that I've seen others having. We actually seated it 2 or 3 times and then took it off and checked it since I had spares.
When I did the final install and tightening the flange seated perfectly flat against the oil pump. Doesn't guarantee that it didn't get pinched in the final install though!
We've run it a couple of times for 15-20 seconds and then that last time for 30 seconds.
I'm getting the reduced power message on the dic, but, I understand that I should expect that if the steering rack harness is not connected.
I changed the link for the YouTube video. I think/hope it should work now.

Last edited by Zmeister; Jan 19, 2019 at 04:43 PM.
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Old Jan 19, 2019 | 05:22 PM
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I still can't see the video.

If you don't have one of those cheap engine stethoscopes you can put a piece of fuel hose or heater hose to your ear and put the other end close to parts of the engine and listen. If you saw good oil pressure when you ran it, let's be logical. You had oil pressure before you started, you changed the oil pump and think you have that installed correctly. What timing chain/gear did you install? Is it possible that there is some mechanical interference under the timing cover? Either the gear or pump is not installed properly, a problem with the new chain damper? Try that hose trick to listen to the timing cover if you are confident in the oil pressure, if not pull the timing cover back off and look for marks or interference.
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Old Jan 19, 2019 | 07:52 PM
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It's my first YouTube video and I obviously don't know what I'm doing yet!
The new timing sprockets are oem GM parts. The timing chain is the katech C5R chain.
The dampener is from a speed shop that's making them on a cnc machine since there are no oem ones available any longer for my bolt hole spacing.
I don't think there's any interference behind the timing cover, but, only way to know for sure is to take off the cover. I'm never really positive about many things anymore. I've ended up mistaken too many times.
We did turn the crank with a ratchet a few times once we got the harmonic balancer back on and didn't hear anything.
I'll look into getting one of those stethoscopes or some hose tomorrow. Can't let the car run very long since the cooling system isn't all hooked back up yet.
Thanks for the thoughts and tips.
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Old Jan 20, 2019 | 02:14 PM
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Posted the YouTube link this time instead of the actual video into my first post.
After a lot of reading on the Forum and plenty of Googling, I connected the steering rack to the wiring harness this morning and that seems to have stopped the knocking!!
Car still runs rough because most accessories are still not connected to the wiring harnesses.
Still trying to decide if I should take everything back apart to double check what's been done so far, or, move forward with the re-assembly.
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