RGPIII

One more video of when I was checking the oil pressure. Not going to run it anymore until I find the cause of this noise.

http://s1361.photobucket.com/user/RG...1gmgy.mp4.html

thirdchildhood

iTrader: (6)

If you raise the revs does oil flow increase?

RGPIII

yes.

AllDodge

iTrader: (1)

Assuming the 40 psi is at idle so the pressure is good and should have plenty to supply cam and lifters. It does sound like the lifters are collapsing and with little oil they are not getting enough. I'm thinking the block was not cleaned out and now the lifter channels are clogged

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mcollinstn

Dodge, that diagram is a smallblock.
A big block is different and oils the rear main journal first.
This feeds the crank, in which oil moves forward, oiling the rods, and each main bearing traveling towards the front. Each main feed upwards to the cam bearing above it. The front main bearing has provisions to oil the timing chain.
The rear cam bearing journal is grooved and feeds the lifter gallery from the back on each side. The gallery runs right thru the center of the lifter bores, and the small diameter portion of the lifter is what passes oil from one lifter to the next as oil passes around that diameter.

Some small base-circle cams can allow standard lifters to drop below the oiling hole in the lifter bore. This would cause starvation to the lifters and top end.
If any lifter bores have been bushed, then the bushing must have the oiling holes aligned properly.

I still haven't heard the noise since the videos still won't load for me.

Best (and cheap) way to isolate weird noises is:

Remove the belts from the motor to rule out any accessory drive item.
Pull the outdrive, so that the drive coupler, U-joints, and driveline noise cannot be making a contribution.

Fire her up. When the noise starts, grab the starter motor and make sure you can't feel any sympathetic hammering on the starter (from a dragging bendix, or misaligned ring gear).
Be extremely aware that exhaust leaks can sound like top end noise, bottom end noise.. Listen CLOSELY around each exhaust port.

You mentioned that you did have a consistent misfire, and pulling plug wires did not silence the noise.
Well, if you have a misfire, pulling plug wires WILL isolate the misfiring cylinder(s). Do your best to figure out which one(s) are misfiring.

As I said earlier, making sure your lifter preload hasn't changed can also help figure out whats up. In fact, some "rebuilds" get returned with the lifter preload never properly adjusted in the first place.

In person, chasing noises is a lot easier, as you can "
get a better sense" of what's happening.

RGPIII

im not quite sure lifter pre load can change, these are the stock non adjustable rockers.

Tinkerer

I say somehow water got into a cylinder and what you are hearing is a bent rod. Or bent pushrods because of hydrolock.

picklenjim

Good point. RGPlll, did you shut off the hose when you turned it off and started it right back up? You need to pull the plugs on that bank, see if one stands out from the others and do a compression check down that side. Need to determine which cylinder this is happening on and then go from there inspecting closer.

dereknkathy

I hydroed a small block and put an S-bend in a rod. the sound of piston skirt hitting crank throw was WAY louder than any rod knock. And it is one bang per rev like a rod knock. And you KNOW when you hydro a motor. Goes from spinning fast on starter to stopping dead. And you think "that was not good". and all 16 pushrods can be seen and spun by hand here. what if OP were to pull the back 2 lifters and spin the oil pump with a pre-oiler in a drill. how much oil flow SHOULD he see at each lifter bore?

JRider

iTrader: (1)

Sounds lifter like to me.