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Bad Rod Bearing
- Thread starter Duiser Offroad
- Start date
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- #2
More photos of the progress
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- #3
Here you can clearing see #3 bearing is completely gone. And wear marks on the crankshaft.
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- #4
Bearing is in the picture
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- #5
The problem was difficult to diagnose as the knock and "slap" were hard to pinpoint. At first we thought it was piston and maybe timing chain. Took valve cover off and checked timing chain but, looked fine. It was hard to see pistons. #3 looked different than the rest but, still fine. Drain oil but, no shavings.
Removed lower oil pan and realized we had very large metal shavings and a lot of them. Concluded it must be piston due to quantity.
Removed engine to find pistons we fine. But, #3 was VERY clean.
Removed upper oil pan and saw #3 bearing was super loose, then discovered it was gone.
Next steps, new crankshaft and bearing. I need to look at #3 piston as well for wear. Probably going to do other PM while in there. Of course new HG, new timing chain and tensioner too. need to look at water pump.
Removed lower oil pan and realized we had very large metal shavings and a lot of them. Concluded it must be piston due to quantity.
Removed engine to find pistons we fine. But, #3 was VERY clean.
Removed upper oil pan and saw #3 bearing was super loose, then discovered it was gone.
Next steps, new crankshaft and bearing. I need to look at #3 piston as well for wear. Probably going to do other PM while in there. Of course new HG, new timing chain and tensioner too. need to look at water pump.
inkpot
SILVER Star
So is the rod bearing missing from just one side, or from all the way around the crank? I saw one once that had submarined around the crank and there were two halves stuck in the rod side while the cap side was empty!
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- #8
I bought the vehicle as is. 170k miles. Head gasket looked good. Oil pressure was fine. I believe the PO probably ran the truck low on oil. The engine also had a lot of oil residue covering it.
No sound clip. Although there have seen other rod bearing posts with similar noises (sound clips) which lead me to lean in that direction before tear down. The "slap" appears to have been the piston hitting the head. Which is why the #3 piston was so clean.
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Thanks for the info. So what's the Mud consensus why that one rod bearing would self destruct, blocked oiling hole/galley??
Anyone remember; was there a TSB about some engines with ?improperly torqued rod bolts or bad rod bearings ie: factory production error??
Anyone remember; was there a TSB about some engines with ?improperly torqued rod bolts or bad rod bearings ie: factory production error??
This looks so much like mine it's not even funny. On mine, I've determined (with help) that the most likely culprit was the front crank bolt. I noticed when I was turning the crank with the front bolt that it "moved" a bit. I knew that wasn't right. Turns out, that bolt clamps the drive gear for the oil pump and power steering. I later learned that that particular bolt should be torqued to 200 something ft-lbs. That's a LOT, and mine was a hair past finger tight.
My engine did the same thing to the #5 rod bearing. It ate the journal as well, so it scrapped the crank. The rod was beyond resizing as well. Luckily, I found both items from a friend for a reasonable price, very reasonable.
My piston was slapping the head, ever so slightly. I could hear the piston tap and then go away for a couple of revs. That was probably the bearing parts moving around the journals. Mine were tin foil when I got to them.
I hope to have my block back from the shop soon. Then the fun begins!
My engine did the same thing to the #5 rod bearing. It ate the journal as well, so it scrapped the crank. The rod was beyond resizing as well. Luckily, I found both items from a friend for a reasonable price, very reasonable.
My piston was slapping the head, ever so slightly. I could hear the piston tap and then go away for a couple of revs. That was probably the bearing parts moving around the journals. Mine were tin foil when I got to them.
I hope to have my block back from the shop soon. Then the fun begins!
So are you going with a new short block?
I'm afraid thats what wine will look like when I tear it down. I couldnt tell if it was up top or down low. Probally because it was both
rod knocking and piston slapping the head. You may be better off doing what I did. And finding a good used rebuildable long block for about $500.
rod knocking and piston slapping the head. You may be better off doing what I did. And finding a good used rebuildable long block for about $500.
how about poor choice in oil filters? I too often see large aftermarket filters that have no check valves installed on these motors.
On start up the oil pump has to pump enough oil to fill the filter and the passages in the block before maintaining pressure. So basically a delay in pressure during the high idle period on initial start up.
I've changed over a few trucks to the small OEM filter and have seen the start up knock reduced or completely eliminated afterwards.
On start up the oil pump has to pump enough oil to fill the filter and the passages in the block before maintaining pressure. So basically a delay in pressure during the high idle period on initial start up.
I've changed over a few trucks to the small OEM filter and have seen the start up knock reduced or completely eliminated afterwards.
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I still don't have a REAL reason for why this may have happened to me. I do know that my front crank bolt was VERY tight. So I doubt that is why. Just sent the block etc off to the shop today. Will know more tomorrow.
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Previous owner had a fram filter on it!!!! maybe???
If it was a system-wide problem with the lube oil, like no or low pressure or filter bypassing debris, you'd see wear on the the mains and the surviving rod bearings. IMHO. If localized to one rod bearing, could be rogue debris particle. What does the main bearing look like that feeds that rod journal?
use the 90915-20004 filter or go and buy an engine rebuild from CDan....
$8.75 a filter. You can't go wrong.
$8.75 a filter. You can't go wrong.
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- #18
Machine shop got back to me. Block, head, pistons are all fine. #3 rod needs to be replaced and crankshaft is salvageable.
That said, when I look at rebuilding the motor and putting it back into the truck, I'd much rather put a 6bt in.
So I'm selling the complete motor. 174,xxx miles. New owner would have to buy new gaskets, and piston rings, #3 rod, bearings and re-manufacture or buy new crankshaft.
$800.00 OBO
That said, when I look at rebuilding the motor and putting it back into the truck, I'd much rather put a 6bt in.
So I'm selling the complete motor. 174,xxx miles. New owner would have to buy new gaskets, and piston rings, #3 rod, bearings and re-manufacture or buy new crankshaft.
$800.00 OBO
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- #20
I was going to put the engine back in myself and I get work and parts at cost so its hard to say.
500.00 in parts?
