Knock knock!

[alan]

Who's there? :rolleyes:

What will make an engine knock besides main and rod bearings? The mains look OK so far (cap side) except for a little discoloration. I will look at the rods tommorrow, but I didn't see anything unusual when I turned the engine over or wiggled the rods on the crank. If I stacked a rod bearing I think I'd get more than a muffled knock, more like Bang-Bang! (been there!) The flex plate is a thick SFI approved unit. The valve train looks OK. Didn't see pieces of piston missing! :Do No:

Any ideas for other places to look?

[RACEBUICKS]

I had a muffled KNock and found it to be a loose torque converter bolts and I double checked the flywheel bolts too :Do No:

[alan]

I did find the center of a converter stuck in the end of the crank where the pilot bushing goes! I'll double check the bolts holding the flexplate on.

If I don't find anything, I'll put it back together and run the poop out of it! :bglasses:

[alan]

Well, I found nothing nasty with the rod bearings. Other than piston slap or a loose wrist pin, (and converter bolts) I don't know where else to look.

I hope I don't find out the hard way! :ball:

[GSXMEN]

Have you tried isolating the area of the noise with a stethoscope?

Wouldn't the cam bearings/cam make a noticeable noise if one or more went bad?

Maybe the fuel pump rod/timing chain area?

Let us know what you find.

Scott

[QuikBuik]

Scott just hit my next question. Fuel pump arm??

[alan]

Nope, I'm using an electric pump. Here's a picture of the cap side of the rod bearings.

[GSXMEN]

How's the crank look? The bearings don't look bad - although the top one looks like it's wearing a little different.

Scott

[redbuick]

alan, make sure none of the rods/rod bolts are hitting the oil pan in the front half, there isn't much room here and if the pan is bent in just a little it can make contact here....seen it happen......

[alan]

The main bearings look about the same as the rods. The top rod bearing looks "stained", but feels smooth. The engine has a main girdle, so the pan is about 1" lower than normal.