strange crankshaft wear
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Joined: Nov 2001
Posts: 95
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strange crankshaft wear
I pulled the oil pan off of the car today and also removed the rod ends.
Upon inspection of the crank, I noticed some wear (like scratches where the journals are) but I also noticed a strange pattern.
Where each set meets the crank there is a valley, where I suppose the bearings do not touch the crank. This valley where no bearings have been riding is elliptical. On one side of the crank (let's say lower) it is smooth and flat with the crank. 180 degrees away from that it's raised up about 1/16th of an inch, higher than the bearing surface.
Why did that happen?
Upon inspection of the crank, I noticed some wear (like scratches where the journals are) but I also noticed a strange pattern.
Where each set meets the crank there is a valley, where I suppose the bearings do not touch the crank. This valley where no bearings have been riding is elliptical. On one side of the crank (let's say lower) it is smooth and flat with the crank. 180 degrees away from that it's raised up about 1/16th of an inch, higher than the bearing surface.
Why did that happen?
Safety Car
Joined: Mar 2000
Posts: 3,620
Likes: 2
From: Hillsboro OR
Re: strange crankshaft wear (jopod)
Sounds like the bearing wore into the crank. This can happen without the bearing attaching itself to he crankshaft and spinning. Did the engine assembler put the grooved bearing half in the block or the bearing cap ?
It should be in the block. If they did that correctly, you probably have an oiling problem. Did they put assembly lube on the bearings ?
You'll have to remove the motor and pull the crankshaft and have it turned. You'll also have to check the rest of the rotating components for damage.
I had to pull my 383 and re do it after the first attempt so I know how you feel.
It should be in the block. If they did that correctly, you probably have an oiling problem. Did they put assembly lube on the bearings ?
You'll have to remove the motor and pull the crankshaft and have it turned. You'll also have to check the rest of the rotating components for damage.
I had to pull my 383 and re do it after the first attempt so I know how you feel.
Burning Brakes
Joined: Nov 2001
Posts: 1,189
Likes: 2
From: Austin TX
Re: strange crankshaft wear (jopod)
The reason for the uneven wear is that the power stroke puts alot more pressure on the crank journal during part of its rotation, which causes the journal to get out-of-round, thus causing the elliptical pattern you see in the areas that the bearings don't touch.
