Bad knocking on cold start up.
doubt its a rocker, but since I don't know anything (quote from above) check this post out! listen to the video and then check out #15 reply.
https://ls1tech.com/forums/generatio...ine-noise.html
https://ls1tech.com/forums/generatio...ine-noise.html
Last edited by JOHNNY59; Dec 2, 2013 at 08:24 PM.
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doubt its a rocker, but since I don't know anything (quote from above) check this post out! listen to the video and then check out #15 reply.
https://ls1tech.com/forums/generatio...ine-noise.html
https://ls1tech.com/forums/generatio...ine-noise.html
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Before you try and start it again see if you can turn the engine over with a ratchet on the crank bolt. With it knocking that loud and it stopped running on its own I would guess it either dropped a valve or hydrolocked.
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The last three noisey LS motors I have fixed was with LS4/LSA oil pumps (an LQ9, LQ4, and an LS6). They all had good oil pressure, 40 at idle and 40-60 driving. The two LQ motors had the exact same knock on start up and the LQ9 started having a knock at all times. The LQ9 was my cousins Denali, well taken care of. All were fixed with a new pump.
May not need to drop the pan,(yet) dump the oil into a real clean container and examine it. If it's a rod bearing there will be metal flakes and particles in the oil. You could try draining the oil though some type of filter to catch the carnage. That doesn't sound good. Once heard a cracked flex plate make a similar sound.
The cam is spinning at half the engine speed a rocker or valve would be rythmic and would not vary linearly with rpm. This does, sounds to me bottom end related a hole in the piston would def make it run like that and yes I have seen quite a few spun bearings that make the engine shake and stall like that. Its not very uncommon, a valvetarin problem would be roughly at half engine speed and wouldnt be that "heavy" in sound. Oem rockers very rarely if ever fail and break besides the needle bearings
Last edited by redbird555; Dec 10, 2013 at 03:34 PM.
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Wow prolly a broken piston, rain water leaks past the windshield cowling and runs down on top of the intake manifold. The intake is loose and the water leaks past the seals and into the engine. As you start you slug a cylinder with water and it hydro locks breaking the piston-rod etc. Good Luck.
I knew it wasn't a bearing.....
I knew it wasn't a bearing.....
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Be sure to seal the windshield cowling so this never happens again. You may be able to fix this with a used rod and piston. Pull it apart and see how bad the damage is. If it didn't crack the block you can fix it.