Abnormal ticking or knock? Videos so you can hear it.

[8bit]

I know Honda valvetrains are not exactly quiet but some ticking sound really stood out to me last night. Here's two videos so you can hear it. The video is just a black screen but the sound is good.

Note: Motor is warm. 136k. Fresh 10w30 AMSOIL. Not sure when last valve adjustment was done. This is after cruising around for about two hours.

I think the abnormal sound (to my ears anyway) is more noticeable in the second video near the end. It's a deeper tone than the normal valvetrain noise and it's not a consistent noise. I'd say more of a knock than clatter, knocks 3 times, pause, knocks 3 times, etc.

Is it something I need to look into or sounds fine to you?

I can get more video today if needed.

 

[silver2002]

Like Music.

Sounds good to me.

 

[imflipside]

The knock at the end sounds a little off to me, but otherwise it sounds pretty good.
When did you last replace your LMAs (Lost Motion Assemblies), do a valve reset or replace your spark plugs?

 

[8bit]

The knock at the end sounds a little off to me, but otherwise it sounds pretty good.
When did you last replace your LMAs (Lost Motion Assemblies), do a valve reset or replace your spark plugs?

Yes that knock at the end is what sounded off to me too. Had to go look through previous owner's receipts. I've only had the car less than a year. Talked with ScienceOfSpeed and they initially said it might be the LMAs as well. (Waiting to hear back after I found LMAs were recently replaced. The car is not with them, just emailing. I'm not in Arizona.).

LMAs and Timing Belt done at an Acura dealer.
3/8/13 126k (only 10mi ago)
PART #14820-PCB-305 (x12)

I'm assuming the valves were adjusted then too. Not sure on the spark plugs, but I bet it was recent (last 2-3 years). I'll dig through more receipts.

- - - Updated - - -

New videos from today. Didn't drive it. Just let the motor warm up to operating temp. When the motor was cold I didn't notice the knocking noise, but as it got warm I could hear it again.

 

[davidf]

That is definitly an abnormal knock. You need to a sound clip from the oil pan area.

 

[dirtbag]

If possible when idling pull a plug wire one at a time. If the sound goes away when you pull a wire, it could indicate a bottom end issue with that cylinder. Do you have your oil analyzed?

 

[docjohn]

I had a weird ticking from the engine bay..it turned out to be a broken screw on my fancy aftermarket cam plate cover.

 

[NSXCessive]

Yes that knock at the end is what sounded off to me too. Had to go look through previous owner's receipts. I've only had the car less than a year. Talked with ScienceOfSpeed and they initially said it might be the LMAs as well. (Waiting to hear back after I found LMAs were recently replaced. The car is not with them, just emailing. I'm not in Arizona.).

LMAs and Timing Belt done at an Acura dealer.
3/8/13 126k (only 10mi ago)
PART #14820-PCB-305 (x12)

I'm assuming the valves were adjusted then too. Not sure on the spark plugs, but I bet it was recent (last 2-3 years). I'll dig through more receipts.

- - - Updated - - -

New videos from today. Didn't drive it. Just let the motor warm up to operating temp. When the motor was cold I didn't notice the knocking noise, but as it got warm I could hear it again.

Hard to say which LMA's you got from dealer that part # you listed comes back as 91-99. In '00 Honda revised the design from the old hydraulic mulit piece design to a single spring in all '00-'05. The spring is slightly shorter requiring a spacer to make up the difference in height. I believe SOS is the only one that includes stainless inserts to correct this otherwise the old design will tick/click again in a matter of time ask me know I know? lol I recently did the LMA's in my project '91 she is quiet now.

Is your ticket from the top or bottom of the motor?

-See post #12 from my build http://www.nsxprime.com/forum/showthread.php/164964-NSXCessive%92s-%9291-Project-quot-Sliding-Knife-quot-Build

 

[8bit]

It sounds like it's coming from the top of the motor. The valvecover at the rear is were I can hear it pretty clear with a stethoscope. I can also kind of hear it from the oil pan (w/ the stethoscope) but it's not as loud.

The car was at a local Honda performance shop this week. They think it's the valvetrain too. Had the valves adjusted. Cylinders 1 & 5 were barely out of spec. The sound is still there. They said the LMA is the newer spring type. Can you tell which type of LMAs I have from these pics (shop took them for me)?

If these are the newer spring type, do you think the noise could be happening because it doesn't have the SOS inserts? I'm sure the Acura dealer that replaced the LMAs did not use an SOS kit to retrofit them.

 

[8bit]

Bringing this thread back to life.
I never really updated what happened with my car, and I've got messages from other members asking about it (because their cars make similar sounds).

I ended up shipping the car to Science of Speed. I didn't want to risk a non-specialist trying to diagnose the issue.
Well turns out it only needed a valve adjustment!



While the car was there they took care of some other maintenance (replaced all coolant hoses) and I got the SOS headers. Best possible outcome for sure. The motor has been perfect ever since. :biggrin:

 

[RC-DEVIL]

Honestly, i just love [MENTION=4260]ScienceofSpeed[/MENTION]. I wish there was another branch in Atlanta lol, SOS in my opinion sets the benchmark in the USA for labor rates/pricing on NSX servicing. I refuse to pay anything higher than what SOS charges. Thank you for sharing the invoice!