GM 5.3 ltr Rod Bearing failure need help
02-05-2007, 01:20 AM
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GM 5.3 ltr Rod Bearing failure need help ***Newbie mistake I moved this to the Truck forum. ***
Removed the oil pan (Off LS1 motor) and the pickup tube was loose where the flange bolts into the block at the front of the motor.
Automatically thought this was the culprit of the low oil pressure and Rod bearing failure. Bought new bearings for the rear most rods (they were both damaged) but the crank was ok. Buttoned it up and it ran fine.
Then again today after about 4 hours the knock is back. I can hear it better at the rear which would tell me the same bearings are bad again.
Oil pressure at idle is 25pds. mid-throttle is 35-45ish I can get the oil pressure up to 50+ but that is moving at a good pace. Pressure was lower but not much before fixing the pickup.
What is a safe/good pressure for these motors. I did a google search and no luck.
I will wait to tear it apart again until I get home.
WTF is going on here.
I will buy a Oil pump from Summit and put that in as well but is there more than that wrong?
Rod caps were also fine.
anything else??
Thanks.
Removed the oil pan (Off LS1 motor) and the pickup tube was loose where the flange bolts into the block at the front of the motor.
Automatically thought this was the culprit of the low oil pressure and Rod bearing failure. Bought new bearings for the rear most rods (they were both damaged) but the crank was ok. Buttoned it up and it ran fine.
Then again today after about 4 hours the knock is back. I can hear it better at the rear which would tell me the same bearings are bad again.
Oil pressure at idle is 25pds. mid-throttle is 35-45ish I can get the oil pressure up to 50+ but that is moving at a good pace. Pressure was lower but not much before fixing the pickup.
What is a safe/good pressure for these motors. I did a google search and no luck.
I will wait to tear it apart again until I get home.
WTF is going on here.
I will buy a Oil pump from Summit and put that in as well but is there more than that wrong?
Rod caps were also fine.
anything else??
Thanks.
Last edited by patchzx7r; 02-05-2007 at 01:36 AM.
02-05-2007, 05:02 AM
#2
If you spun a rod bearing, you will have to do more than just replace them. You need to tear the engine completly down and take the crank to a machine shop. It probably needs to be turned down to true it up. You also will have lots of little metal pieces inside the engine that you have to find a way to get out of the oiling system.
