General Maintenance & Repairs - Piston Slap/Bad Bearing Consequences?




MyFirst01
05-24-2012, 08:41 PM
I still haven't found out what the noise coming from my motor is. I talked to my dad about it saying how I don't want to damage the car and he tells me its fine. Lets assume that it is a spun bearing for a second. What will happen exactly if the engine decides to give out due to the bad bearings? I don't want to be running 70 down the highway and end up dead.

So... What can I expect to happen if I continue to drive this thing? I planned on taking it to the track in the next few weeks, but I'm not confident it will hold.

Also, the oil gauge is almost all the way to the right (like there's way too much oil pressure). And sometimes, I try to turn the car on and the motor just gives out. I was thinking this might be a starter problem, but the motor turns on and almost surges in a way. It will revv up to about 200 rpm, die back down, then revv up again, then die. After this it starts normally. I've been trying to figure out what it is, but I'm not sure what I should be looking for. Any info is helpful. Thanks guys.


dracula4999
05-25-2012, 10:48 AM
Usually if you spin a bearing the engine will seize up or chunk a rod thru the side of the block. From what i understand these engines make some bottom end noise all the time, i dont know for sure cause mine isnt running yet. If it throws a rod going 70 down the highway it will probably scare the S**t out of you, but it wont kill you, just make a bunch of noise. Im not saying your about to blow it up, but i have seen several ls1's throw the #5 rod, and have seen alot of guys rebuilding theirs cause of worn out bearings. Without hearing the noise you are hearing, cant really help much. Id say drive it till it blows, or pull the engine while its still good and put better rods in it cause the gm rods are junk, new bearings, and have the crank checked.

patSS/00
05-26-2012, 12:25 AM
The surging thing sounds like it's doing an idle re-learn, for example it will do that the first time you start it after the battery's been disconnected, then the next time you start it will be normal.


MyFirst01
05-26-2012, 10:09 PM
All I know is this knocking noise is embarrassing.