LS3 Won’t turn over.
07-31-2020, 10:03 PM
#1
LS3 Won’t turn over. Alright guys, replaced the cam, oil pump, and springs. DOD delete and VVT delete.
I replaced the cam and oil pump and the the motor turned over fine by hand. Pulled heads and replaced lifters and valley pan. Motor still turned over.
Installed heads and the motor would turn all the way over but felt like it had a drag, so I carefully rotated some more and after a few complete revolutions it hung up and now won’t turn CW or CCW.
Any ideas?
I have disconnected valve train and still won’t turn over. Cam gear is off. Pulled rockers back off and all valves are closed.
I replaced the cam and oil pump and the the motor turned over fine by hand. Pulled heads and replaced lifters and valley pan. Motor still turned over.
Installed heads and the motor would turn all the way over but felt like it had a drag, so I carefully rotated some more and after a few complete revolutions it hung up and now won’t turn CW or CCW.
Any ideas?
I have disconnected valve train and still won’t turn over. Cam gear is off. Pulled rockers back off and all valves are closed.
07-31-2020, 10:09 PM
#2
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If you do not have any the valve train parts connected and the engine won't turn over by hand then something is way wrong. I'm taking it as the engine is still in the vehicle. Did you spin the motor over by hand with the lifters and heads installed before installing the PR's and rockers?
Last edited by 01CamaroSSTx; 07-31-2020 at 10:18 PM.
07-31-2020, 10:14 PM
#4
07-31-2020, 10:20 PM
#5
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Man you need to go back through what you did and double check everything.
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G Atsma (07-31-2020)
07-31-2020, 10:35 PM
#6
If you do not have any the valve train parts connected and the engine won't turn over by hand then something is way wrong. I'm taking it as the engine is still in the vehicle. Did you spin the motor over by hand with the lifters and heads installed before installing the PR's and rockers?
I have not removed the heads yet but I have a hard time believing the head has anything to do with it cause the valves are all closed.
07-31-2020, 10:56 PM
#7
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I'm trying to think of what could be causing it to bind up if you've removed the valve train components from the engine and cylinder heads. Are the spark plugs removed from the heads?
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07-31-2020, 11:06 PM
#8
Yep no spark plugs.
I’m at a loss as well. Probably gonna pull the heads off tomorrow since that was the last thing I did to it and start working my way backwards.
Sounds silly but I hate to order new heads bolts. LOL
I’m at a loss as well. Probably gonna pull the heads off tomorrow since that was the last thing I did to it and start working my way backwards.
Sounds silly but I hate to order new heads bolts. LOL
08-01-2020, 12:04 AM
#9
TECH Enthusiast
Know the feeling. Built my LQ9 two years ago then installed PRC heads last month. This time I ordered ARP bolts for $105 so If they ever come off I won't have to purchase new bolts. I'd been ahead if I would have bought the ARP's to begin with.
08-01-2020, 10:29 AM
#11
Is the engine on a stand or in the car? Did you have the oil pan off? If you did I would start there, Pull the pan and windage tray and make sure nothing fell down into the engine and wedged between the block and crank and make sure the windage tray has clearance.
08-01-2020, 11:10 AM
#12
Ok guys, I just pulled the heads off and the engine turns over perfect cam is turning as well. There was nothing in any of the cylinders. I used new stock .054” head gaskets and new TTY bolts. Oil pump and everything is connected like it would be normally.
What do you all think?
What do you all think?
08-01-2020, 11:42 AM
#13
Ok I think I found the problem. The. Bite size on the head gaskets that I put on new is slightly smaller than the bore of the original head gasket.
What do you all recommend for head gaskets?
What do you all recommend for head gaskets?
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01CamaroSSTx (08-01-2020)
08-01-2020, 11:42 AM
#14
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What bore on engine and bore on head gaskets?
08-01-2020, 11:48 AM
#15
To find out the bore size on the gaskets are 3.95. Mahle 54442. LS3 has a bore diameter of 4.065.
I ordered the DOD delete with the gaskets from Scoggin Dickey and I believe they must have sent the wrong head gaskets. We’ll see if they make it right. The kit was for the 6.2.
I ordered the DOD delete with the gaskets from Scoggin Dickey and I believe they must have sent the wrong head gaskets. We’ll see if they make it right. The kit was for the 6.2.
08-01-2020, 12:18 PM
#16
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That's what I was suspecting. Pistons hitting the hg
08-01-2020, 12:22 PM
#17
Yep. Just as much my fault for not inspecting sizes before installing but you know I just “figured they were right”. But gonna go ahead and order ARP head bolts this time and we’ll see if SD will send me a set of correct gaskets.
Thanks to everyone for their input.
08-01-2020, 12:28 PM
#18
TECH Enthusiast
That solves the mystery... that's a lot of work to have to redo. If it's on their end I'm sure they'll take care of it. If so ask for the ARP bolt upgrade for your trouble lol. The ARP bolts go by three torque steps and not by angle, it's worth the upgrade even if you have to pay the price difference between the OEM bolts.
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Old Geezer (08-02-2020)
08-01-2020, 12:31 PM
#19
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