The dreaded knocking noise?

[Jonlopes]

Originally Posted by 67 chevelle

faulty pcv valve will knock [i have experienced this], brake booster could be similar ,[thought i have never experienced this] , some other things i have experienced that made a knock were , a broken piston ring ,rockers hitting valve covers , torque converter bolts hitting transmission ,, and of coarse the obvious crank bearing , with a bad crank bearing you will loose oil pressure

That gives me hope because my oil pressure is a nice and steady 30 psi at idle and 60-70 PSI while driving.

[rharp]

My 1969 396 had a fairly subtle knock during idle that would speed up and become more pronounced with an increase in RPM. It seemed to be coming from the driver's side. I tore it apart a month or so ago to a couple flattened lobes on the cam and shavings got into a couple cam bearings. The motor probably had 10k miles on it after a rebuild. This was at least its 2nd rebuild and it ate the cam up on each one. I'm boxing it up and saving up for a crate motor. Screw it. lol

[Fitz]

Originally Posted by Jonlopes

My engine is making a noise I hate to even think the “K” word but it is more of a knock than a tick. Kind of like if you were knocking your knuckles against a door or something.


Are there any good things to try or should I take it to a mechanic who better understands internal engine issues?

There are as many things that can cause a 'knock' as there are opinions on this board. I always get my 18 inch screw driver when I'm looking for a 'knock' and I probe around the engine by pressing the blade to a likely spot and pressing my ear to the handle. Use it as a stethoscope and probe down each valve cover. If you don't find a sopt that's louder than all of the rest it is unlikely there is a problem under the valve cover (lifters hitting, etc.). Probe each of the header bolts...and on and on and on till your are just sick of that thing sticking in your ear. Sooner or later, you'll get a strong hint of where inside the problem is. Then you need to decide if you attempt a teardown or you take it out to a shop. Your choice. Good luck!

[Jonlopes]

I tried a vacuum gauge and it pulls a steady 17 which is not bad.

Here is a video where you can hear the knocking. click on the link below and click on the picture of the engine.

http://dadgummit.smugmug.com/Cars/Random-forum-uploads

It seems like it is louder under the truck than above but that can be because of the noise of the fan and carburetor up top. What do you think?

[Jonlopes]

Bump hoping some of the guys who chimed in before can watch/ listen to the video linked above and make suggestions.

[kingsolver72]

Originally Posted by Jonlopes

Can that be checked without a full tear down?

With the engine running pull the spark plug wires off one at a time. Listen to see if the knock goes away on any of the cylinders.