Well DF folks, here I sit stumped once again...

Thought it was a knocking noise from the oil pump suction tube... Pulled it and unplugged the coil, and the darned noise was still there! It seems to me like the crank was slightly touching the tube, but that isn't evidently causing the noise!

I've got the oil pan off, and am debating pulling the bearings and inspecting. All the lifters are getting oil, and the rocker bolts are tight. So I'm fairly sure it's gotta be a bearing somewhere. Someone mentioned that a bad throwout bearing can make the noise, but I'd have to pull the tranny to check it. So I'm looking for opinions. Any help is appreciated!

My plan is this: Pull the tranny and check the throwout bearing first, because if it's anything related to lifters or bearings in the engine I'm gonna have to pull the engine which'll require me to pull the tranny anyways...

 

A bad throwout bearing will be easily verified by pressing in the clutch. At idle, if the sound stops when you press in the clutch, its a bad throwout. Otherwise, you are definatly looking at something engine related.

 

Not likely a main bearing. They don't knock so much....rod bearings - different story!

Eliminate everything else first!

 

No the noise does not stop at idle with the clutch in.


Prolly rod bearings then... Cuz the noise is loud.... Loud as, well, dropping a hammer held at arms length to the floor without force, just gravity...

So I'm gonna put the new pickup tube in the truck and put the oil pan back on, and fill 'er up with oil and see how it sounds then. If it don't go away then, I will declare it time to pull the engine. Oh, once I get the pan back on I'll pull the serp belt just to make sure that way... I'll update later .

 

As long as you have the pan off, plastigage the rod bearings.

 

Are you saying you spun the motor with no oil in the system? Test the big end of the rods using a whatever see what one has play in it.

 

I unplugged the coil so it wouldn't fire, then I turned it over. I had heavy grade oil in the system so I'm not worried about damage. I only turned it over once to ensure clearance.

I've verified that the rod bearings are going out, they have too much slop so that's why it was hitting the oil pump suction tube.

I'm gonna pull this engine, I'm getting another engine lined up so I can basically just drop it in. What I'm gonna do with this one I don't know yet.

 

a faulty crankshaft main or rod bearing usually makes a knocking sound that is very deep and pitch. Main bearing knock is usually a thumping noise most noticeable when engine is first started. Connecting rod bearings also cause a heavy knocking sound and engine oil pressure may also be low especially at idle.
When the cylinder with the faulty connecting rod bearings is disabled during a cylinder balance test, the knocking sound will diminish.
Camshaft bearings usually do not cause noise unless severely worn.
A piston pin with excess of clearance often makes a double click noise in the engine when its idling and it sometimes can get loud.
When performing a cylinder balance test, piston noise can increase when the faulty cylinders is disabled (the opposite reaction of a bad connecting rod bearing).
Lifters also make a distinct noise loud ticking sound. 1 way to tell the difference between that is to remember that the camshaft operates at half the speed of the crankshaft.
That's everything I could think of

 

Well I've got a engine lined up now to replace the 360 that's in it right now. So I'm gonna have some fun pulling a engine now . I'll start a engine swap thread LOL.

I tried the cylinder balance test, just made the engine run rougher, and the noise was still there...

 

be cool to find out what it is when u go iside the old motor, curius could it be a lifter ?