Are these bearings spun? need help (w/ pics)

[American_Muscle]

Hey guys,

I've been hearing a ticking/knocking sound coming from the bottom end of my engine.

Just today I finished removing the kmember and oil pan to check the carnage.
I suspected a spun rod bearing.
I removed 3 rod caps.
The rod bearing on the first rod cap I removed came out separate.
It seemed to be clinging to the crankshaft.
I pushed the piston up the bore to get to the other bearing and it was also no longer attached to the rod.

The other two caps still have their bearings firmly attached.
The two bearings from the one rod are badly scratched and scarred on the side where the bearing meets the crankshaft. So basically both bearings were spun?
Pieces of metal (metal shavings) appear to be peeling off the bearings.
Some of these shavings were also found in the oil pan (but not many).

I checked the crankshaft journal where the bad bearings were. It did not looked to be scratched at all.
Is this a spun bearing? Even if the bearings are so scratched and the crankshaft has no damage what so ever?

Attached are pictures of the bearings.

What do you guys think?

Thanks,
Patrick

View attachment 383277
View attachment 383278
View attachment 383279

 

[the98stang]

Those bearings do look a little worn. If you found a little metal in the oil pan, they are definitely bad. I think you caught the problem just in time. Replace the bearings and the noise should stop.

 

[American_Muscle]

Aren't the bearings supposed to be firmly attached to the rod cap?
As soon as they become loose that's it..they're spun, right?

All other caps had their bearings attached very tightly.
I couldn't even budge them.

But how do the bearings get that worn if the crank journal isn't?
I mean the metal is literally peeling off.

They are very worn..it's hard to see in the pictures but they have pretty deep cuts in them.

The ticking sound was pretty loud.

 

[Skud]

The bearings just sit in the rod cap. To prevent then from spinning there is a notch at the end of each bearing. This notch butts up against the corresponding notch on either the rod cap or the rod itself.

The bearing just sits in there and it shouldn't be too hard for it to come out.

Riley

 

[American_Muscle]

But the scarring is a sure sign of a spun bearing right?
It looks like someone took a knife and scarped pieces of the bearing off.

I just thought it was weird that the bearings that were scratched up were also loose and the others weren't.

 

[trinity_gt]

When the bearing spins, alot of damage is done to the rod's big end. Post some pics of both halves of the rod (rod and cap.)

What does the crankshaft look like?

 

[Skud]

When the bearing spins, alot of damage is done to the rod's big end. Post some pics of both halves of the rod (rod and cap.)

What does the crankshaft look like?

+1

I was going to say post some pics of the backside of the bearing too. It should look pretty marked up if it was spinning inside the big-end of the rod.

Riley

 

[American_Muscle]

Thanks guys!
Well I only have the rod caps out.
The other half of the rod is still in the engine.
I'm doing everything with the engine inside the car.
The cap looks just fine on the inside.
Also the outer part of the bearings look fine as well.
It's just the parts that face the crank that are all ate up.

And the crank seems nice and smooth as well.
I drove the car for about 200 miles after it started making the noise.(not hard though)

What could this be?
I checked almost everything else out when looking for the cause of the noise.
Even swapped out the tranny.

 

[blckstng96]

you've come this far,throw some bearing in there and put it back together.if its anything more your going to have to pull the motor anyway.bearings are cheap so throw em in and see where you stand.

 

[American_Muscle]

Yeah you're right.

Is there a decent guideline on how to install bearings, what to look for etc?

Thanks
Patrick

 

[American_Muscle]

Anyone?