Ticking engine noise - please help!
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
People here seem to be chasing piston wrist pin and or spark jump..... I really don't know if your motor was assembled with stockish type pressed in pins with spring locks or the high end forging with floating bronze bushed wrist pins and spiral locks.
I have not built lots of motors in my life time compared to mechanics at a motor machining shop. But do to the fact that you have a lower rpm BBC I have not ever seen wrist pin failure.
Forged pistons have a greater piston to bore clearance because of piston thermal expansion. IT MIGHT ACCOUNT FOR THE PROBLEM DECREASING WITH ENGINE TEMP.
Why it is related to cylinder # 3 is a mystery being so far away. I've listened to motors through a long screw driver and a stethoscope You have to find out if it is in the block or the heads.
I had piston and ring failure that sounded like rod knock in one of my motors. The clue was that it had good oil pressure. Rod bearing failure has decreased oil pressure
I have not built lots of motors in my life time compared to mechanics at a motor machining shop. But do to the fact that you have a lower rpm BBC I have not ever seen wrist pin failure.
Forged pistons have a greater piston to bore clearance because of piston thermal expansion. IT MIGHT ACCOUNT FOR THE PROBLEM DECREASING WITH ENGINE TEMP.
Why it is related to cylinder # 3 is a mystery being so far away. I've listened to motors through a long screw driver and a stethoscope You have to find out if it is in the block or the heads.
I had piston and ring failure that sounded like rod knock in one of my motors. The clue was that it had good oil pressure. Rod bearing failure has decreased oil pressure
Thread Starter
Pro
Joined: Aug 2008
Posts: 744
Likes: 19
From: Salzburg Austria
Hey!
The motor was rebuilt times ago. I checked this since exchanging the cam. How can I figure out if I have forged pistons? If I remove the oilpan, can I see which pistons (forged or stock) are in?
Günther
The motor was rebuilt times ago. I checked this since exchanging the cam. How can I figure out if I have forged pistons? If I remove the oilpan, can I see which pistons (forged or stock) are in?
Günther
Thread Starter
Pro
Joined: Aug 2008
Posts: 744
Likes: 19
From: Salzburg Austria
If I remove the oilpan, can I see which pistons (forged or stock) are in? How can I determine which pistons I have?
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
You can't determine what kind of piston you have by looking at the bottom of them. I have some forged pistons on the shelf and they don't have anything printed on them as to what they are
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Burning Brakes
Joined: Aug 2008
Posts: 878
Likes: 55
From: Deep South Denmark
This boroscope will fit through the spark plug holes:
https://www.amazon.co.uk/dp/B00KV669...767431_TE_dp_1
You may be able to see the numbers on top of the piston with it.
/Karsten
https://www.amazon.co.uk/dp/B00KV669...767431_TE_dp_1
You may be able to see the numbers on top of the piston with it.
/Karsten
Last edited by Danish Shark; May 19, 2016 at 06:23 AM.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,216
Likes: 9,354
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
And you can see the cylinder walls as well. Look for vertical scraping/ gouging
Race Director
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
I understand it's hard to get accurate sound on a laptop. That sound, to me, doesn't sound like the ticking you'd hear with an exhaust leak. It does sound like valvetrain or something else that would create more of a clacking sound. It would be quick and easy to pull the driver's side valve cover to see if anything is wrong on #3. Have you checked under there yet?
Racer
Joined: Sep 2012
Posts: 459
Likes: 6
From: Fort Worth Texas
People here seem to be chasing piston wrist pin and or spark jump..... I really don't know if your motor was assembled with stockish type pressed in pins with spring locks or the high end forging with floating bronze bushed wrist pins and spiral locks.
I have not built lots of motors in my life time compared to mechanics at a motor machining shop. But do to the fact that you have a lower rpm BBC I have not ever seen wrist pin failure.
Forged pistons have a greater piston to bore clearance because of piston thermal expansion. IT MIGHT ACCOUNT FOR THE PROBLEM DECREASING WITH ENGINE TEMP.
Why it is related to cylinder # 3 is a mystery being so far away. I've listened to motors through a long screw driver and a stethoscope You have to find out if it is in the block or the heads.
I had piston and ring failure that sounded like rod knock in one of my motors. The clue was that it had good oil pressure. Rod bearing failure has decreased oil pressure
I have not built lots of motors in my life time compared to mechanics at a motor machining shop. But do to the fact that you have a lower rpm BBC I have not ever seen wrist pin failure.
Forged pistons have a greater piston to bore clearance because of piston thermal expansion. IT MIGHT ACCOUNT FOR THE PROBLEM DECREASING WITH ENGINE TEMP.
Why it is related to cylinder # 3 is a mystery being so far away. I've listened to motors through a long screw driver and a stethoscope You have to find out if it is in the block or the heads.
I had piston and ring failure that sounded like rod knock in one of my motors. The clue was that it had good oil pressure. Rod bearing failure has decreased oil pressure
sounds like piston slap
Thread Starter
Pro
Joined: Aug 2008
Posts: 744
Likes: 19
From: Salzburg Austria
I understand it's hard to get accurate sound on a laptop. That sound, to me, doesn't sound like the ticking you'd hear with an exhaust leak. It does sound like valvetrain or something else that would create more of a clacking sound. It would be quick and easy to pull the driver's side valve cover to see if anything is wrong on #3. Have you checked under there yet?
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I don't even own a compression tester. IMO they are pretty worthless. But leak down testers can actually tell you the health of each cylinder.
I was recently testing my motor.
I was recently testing my motor.
Burning Brakes
Joined: Jul 2015
Posts: 823
Likes: 57
From: Austin TX
Thread Starter
Pro
Joined: Aug 2008
Posts: 744
Likes: 19
From: Salzburg Austria
Hello!
Here we go! I got the endoscope and now I could watch through the spark plug hole.
Pic #1 and #2:
at the piston bottom I can see a sign, or a letter. It looks like a "L" or something similar. Who know what this is?
Pic #3 and #4:
I see scratches at the cylinder wall. Is this critical or "normal"?
Pic #5 and #6:
Do I see the top dead center?
Here a video:
So what do you think? Is the cylinder done and do I have to rebuild the engine? New pistons with 0,03" over?
Or do you think the cylinder looks like "normal" and I can drive it the next years?
And last but not least, do you see the source of the "ticking noise"?
Regards, Günther
Here we go! I got the endoscope and now I could watch through the spark plug hole.
Pic #1 and #2:
at the piston bottom I can see a sign, or a letter. It looks like a "L" or something similar. Who know what this is?
Pic #3 and #4:
I see scratches at the cylinder wall. Is this critical or "normal"?
Pic #5 and #6:
Do I see the top dead center?
Here a video:
So what do you think? Is the cylinder done and do I have to rebuild the engine? New pistons with 0,03" over?
Or do you think the cylinder looks like "normal" and I can drive it the next years?
And last but not least, do you see the source of the "ticking noise"?
Regards, Günther
Burning Brakes
Joined: Jul 2015
Posts: 823
Likes: 57
From: Austin TX
Images like these can be deceptive. It's difficult for someone who can't move the scope around to get a sense of depth or scale. Nevertheless, the marks just above the piston in photo nos. 3 and 4 look like they might qualify as light gouging, not just scratches. If you agree with that, based on what you see in person, you'll need to pull the piston for inspection. The skirt will tell you more about condition and wear. Pulling the piston will also give you a chance to inspect the rod bearing for that cylinder. Be sure to note exactly how everything is installed so it can be reassembled the exact same way if wear is acceptable.
