Topic: Engine noise... can you decipher it?
in Forum: C3 Engines
Already a Member?
Click Here to Login
Not yet a Member?
Click Here to Register for Free!
Okay everyone, I got around to getting the engine recorded... here it is!
Ask away any questions.
http://www.theimam.com/knock.wav
It's 416k and 19 seconds long
Ask away any questions.
http://www.theimam.com/knock.wav
It's 416k and 19 seconds long
SPONSOR AD:: (Our Sponsors help support C3VR)
Former Member
Send PM
BRADENTON, FL - USA
Joined: 8/4/2002
Posts: 669
Vette(s): 1972 convertible 350 auto trans, delux int, air, ps, pb, t/t wheel, pw, 79,000 org miles Rare one year only color
Sounds like a main bearing
|IMG|http://www.c3vr.com/member_uploads/1301_1400/1333/br80.jpg |/IMG|
Ouch! I agree with the other guy's. Sounds like a main.
Good luck, Sarge
Good luck, Sarge

TKO500 5 spd.
Borgeson Steering Box
Born 8/1981
Sequence #3975

Click here to see more pics of my Vette on CarDomain.
Lifetime Member #26
Former Member
Send PM
BRADENTON, FL - USA
Joined: 8/4/2002
Posts: 669
Vette(s): 1972 convertible 350 auto trans, delux int, air, ps, pb, t/t wheel, pw, 79,000 org miles Rare one year only color
is that the orgional engine???
|IMG|http://www.c3vr.com/member_uploads/1301_1400/1333/br80.jpg |/IMG|
No, that's not the original... that's the juiced up engine the PO put in there. It sucked since I've had it, so I'm not that sad to see it go. I've got the original on a stand, but I'm going to rebuild that for peace of mind, before I put it in.
Imran - 74 Convt
Imran - 74 Convt
Former Member
Send PM
BRADENTON, FL - USA
Joined: 8/4/2002
Posts: 669
Vette(s): 1972 convertible 350 auto trans, delux int, air, ps, pb, t/t wheel, pw, 79,000 org miles Rare one year only color
thats good to know that you still have the origonal engine. someday when my engine gets tired i'll put it in a corner somewhere and install a crate engine. i plan on going to the orlando meet around jan 25. hope it warms up a little
|UPDATED|1/14/2003 5:27:53 PM|/UPDATED|
|UPDATED|1/14/2003 5:27:53 PM|/UPDATED|
|IMG|http://www.c3vr.com/member_uploads/1301_1400/1333/br80.jpg |/IMG|
Well, I sure am glad the previous owner did SOMETHING right... this has to be the first positive thing in my books for him, other than owning a Vette :)
I also get the fun choice of deciding what I'll do with the engine that's coming out of the car.
I also get the fun choice of deciding what I'll do with the engine that's coming out of the car.
Former Member
Send PM
arlington, TX - USA
Joined: 11/29/2002
Posts: 30
Vette(s): 1979 Vette L48 Edelbrock Performer EPS Intake, Matching 750 carb Dk blue on Dk blue, 33,000 miles, electric fan and water pump
I just went through the same thing a couple of months ago. It was a rod bearing. It is just as bad as being a main. I got a remanned crank at O'Reillys auto parts with our company discount for $79.00, including the main and rod bearings.
You might as well replace the oil pump while you're at it, because lack of oil is the #1 cause of bearing failure. I ended up doing the entire lower end, and spent less than $400, doing it myself.
Upper end comes this spring, with some goodies I've been eyeballing.
anyways, it isn't hard to do, this was my first rebuild, and I've put quite a few miles on it since. Just seems scary at first.
You might as well replace the oil pump while you're at it, because lack of oil is the #1 cause of bearing failure. I ended up doing the entire lower end, and spent less than $400, doing it myself.
Upper end comes this spring, with some goodies I've been eyeballing.
anyways, it isn't hard to do, this was my first rebuild, and I've put quite a few miles on it since. Just seems scary at first.
Michael and Yolie
Yikes you sure don't need an engine stethoscope to hear that one! 
Sounds to me like rod knock. Bearings have a deeper tone and half the frequency.
|UPDATED|6/11/2003 12:48:24 PM|/UPDATED|

Sounds to me like rod knock. Bearings have a deeper tone and half the frequency.
|UPDATED|6/11/2003 12:48:24 PM|/UPDATED|
Every day man crucifies himself between two thieves - fear of tomorrow and regret of yesterday.
in Forum: C3 Engines
SPONSOR AD: (Our Sponsors help support C3VR)