C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

tapping sound

Thread Tools
 
Search this Thread
 
Old Jan 19, 2013 | 05:18 PM
  #1  
ricwatson's Avatar
ricwatson
Thread Starter
Heel & Toe
 
Joined: Dec 2012
Posts: 18
Likes: 0
From: Fayetteville NC
Default tapping sound

today I noticed my car started tapping loudly. The oil pressure is almost 0 at idle and about 30 in motion. Car has plenty of oil too. Also I noticed if I have to accelerate swiftly a loud knocking sound starts. If I gently accelerate I have no issues. I have a laundry list of things to fix...I really hate to add one more to the do now list. Any one have any ideas?
Reply
Old Jan 19, 2013 | 07:19 PM
  #2  
Scottd's Avatar
Scottd
Drifting
10 Year Member
 
Joined: Jul 2011
Posts: 1,697
Likes: 139
From: Syracuse NY
Default

0 PSI at idle? Is the 'knocking' a metallic 'ting' that gets worse with RPM and almost sounds like something from the inside is trying to break out? You my friend may have smoked a lower end bearing. Yep. Time for a total teardown or motor replacement. Sorry to be so blunt, but I had it happen to me. What was worse was the engine (purchased used from a buddy) 'supposedly' only had 30K on a rebuild. It was my first motor swap, had less than 100 miles on it. My oil pressure was the same way, but I thought 'no way do I have 0 pressure at idle, my cheap Sunpro gauge must be wrong.' Then it started.....TANG-TANG-TANG-TANG-TANG.....smoked a crank and end caps on an otherwise decent 4 bolt main.

Good luck.
Reply
Old Jan 19, 2013 | 10:27 PM
  #3  
19LEW71's Avatar
19LEW71
Racer
20 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Jan 2006
Posts: 313
Likes: 3
From: North of Boston Ma
Default

Try to locate WHICH piston by having the car running and pulling the spark plug wire one by one off the distributor. Rev the engine up on each one untill you dont hear it anymore.(Thats the one)
Good luck
Reply
Old Jan 20, 2013 | 05:14 AM
  #4  
diehrd's Avatar
diehrd
Safety Car
 
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
Default

I would stop running motor , pull it and open it up. That way you wont do more damage looking for something you need to pull motor apart for anyway.
Reply
Old Jan 20, 2013 | 10:07 AM
  #5  
ricwatson's Avatar
ricwatson
Thread Starter
Heel & Toe
 
Joined: Dec 2012
Posts: 18
Likes: 0
From: Fayetteville NC
Default

It appears my #4 cylinder isn't firing the header pipe coming off of it was cool to touch while the others were super hot. The oil pressure picked up this morning. Also she is hard to start in the morning.
Reply
Old Jan 20, 2013 | 11:10 AM
  #6  
garygnu's Avatar
garygnu
Burning Brakes
 
Joined: Sep 2012
Posts: 818
Likes: 0
From: coon rapids mn
Default

pull the valve covers and check the rocker arms while you tune the engine over by hand.
Reply
Old Feb 12, 2013 | 09:16 PM
  #7  
ricwatson's Avatar
ricwatson
Thread Starter
Heel & Toe
 
Joined: Dec 2012
Posts: 18
Likes: 0
From: Fayetteville NC
Default

Yeah the rocker arm came off my number 4 cylinder. Like completely off. I havent started it up since. Hopefully I can seat my push rod and just tighten it back down and adjust the valves. If not I feel it will cost some money or time or both...I have to many items I am working on right now. crazy
Reply
Old Feb 13, 2013 | 12:58 AM
  #8  
SuperBuickGuy's Avatar
SuperBuickGuy
Melting Slicks
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2012
Posts: 2,548
Likes: 379
From: Woodinville WA
Default

Originally Posted by 19LEW71
Try to locate WHICH piston by having the car running and pulling the spark plug wire one by one off the distributor. Rev the engine up on each one untill you dont hear it anymore.(Thats the one)
Good luck
be sure, when you do that, that you pull the plug from the HEI cap so you get the full voltage when you get shocked.


the right way to ground spark plugs is with a ground wire attached to a pointed screwdriver... you poke through the insulation to ground out the plug.... or, you can shock yourself
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-1

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-2

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-3

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-4

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-5

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-6

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-7

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-8

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-9

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
Old Feb 13, 2013 | 06:06 AM
  #9  
Indiancreek's Avatar
Indiancreek
Drifting
Supporting Member
15 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jun 2010
Posts: 1,781
Likes: 15
From: Oxford Ohio
Default

Make sure the gauge is correct, no pressure at idle, If that's correct it doesn't matter about the rest, you need to take it apart to see what's going on.
Knocking and no oil pressure is like the doctor telling you you need heart surgery or your gonna be departing soon.
Reply
Old Feb 17, 2013 | 05:52 PM
  #10  
ricwatson's Avatar
ricwatson
Thread Starter
Heel & Toe
 
Joined: Dec 2012
Posts: 18
Likes: 0
From: Fayetteville NC
Default

I have decided to break the motor completely down and rebuild it. It is stocked original from the factory. Any suggestions on upgrades cam, carb etc. I plan to keep the same block and head just replace all the worn parts i.e. lifters etc, timing chain etc.
Reply

Get notified of new replies

To tapping sound





All times are GMT -4. The time now is 01:28 AM.

story-0
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-1
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-2
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-3
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-4
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-5
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-6
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-7
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-8
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-9
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE