Rod, lifter, or something else ?
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Teching In
Joined: Jun 2012
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Rod, lifter, or something else ? Here's the problem: new engine installation, crank for oil pressure without fuel or ignition operative, and it develops a knock while cranking. Engine has sat unturned for many years, but was built and dynoed by one of the best. Bought as a ASA motor, I switched to wet sump, swapped the LS1 PCV set-up for the LS6 setup, and swapped the LS1 heads and intake for stock LS6 gear. Rotating assembly wasn't touched.
So the knock was disturbing, and my initial thought (and still is my best guess) is that it's a rod. Best guess is that the starter wasn't turing it over fast enough for pressure to build adequately, and that would be when damage was done.
So my thought was if it was a rod, I'm not going to blow it twice, so I might just as well try and crank it. And if it was a lifter, at least I'd know that it was getting enough oil pressure to make that problem have a solution.
Starts like a champ, 50-60 lbs consistent oil pressure, but it is a loud noise. We initially thought it was coming from the power steering pump, so I took the drive belt off the accessories, and started it for a 30 seconds or so without the front accessories attached, and it sounded like the knock was coming from the back instead of the front. Very strange.
The best alternative I can think of is that this is a collapsed lifter, or another lifter-related issue. But you never know, and there may very well be another cause that the experts here can think of. The engine has only run for 3-4 minutes total, so it's more than a little irritating that the freaking thing, that was supposed to be a really nice unit, now needs some serious attention.
Here's a video:
http://s155.photobucket.com/albums/s...t=IMG_0232.mp4
So my question is: any possibility of an in-car fix? What would you look at besides rod bearings and lifters?
Thanks
So the knock was disturbing, and my initial thought (and still is my best guess) is that it's a rod. Best guess is that the starter wasn't turing it over fast enough for pressure to build adequately, and that would be when damage was done.
So my thought was if it was a rod, I'm not going to blow it twice, so I might just as well try and crank it. And if it was a lifter, at least I'd know that it was getting enough oil pressure to make that problem have a solution.
Starts like a champ, 50-60 lbs consistent oil pressure, but it is a loud noise. We initially thought it was coming from the power steering pump, so I took the drive belt off the accessories, and started it for a 30 seconds or so without the front accessories attached, and it sounded like the knock was coming from the back instead of the front. Very strange.
The best alternative I can think of is that this is a collapsed lifter, or another lifter-related issue. But you never know, and there may very well be another cause that the experts here can think of. The engine has only run for 3-4 minutes total, so it's more than a little irritating that the freaking thing, that was supposed to be a really nice unit, now needs some serious attention.
Here's a video:
http://s155.photobucket.com/albums/s...t=IMG_0232.mp4
So my question is: any possibility of an in-car fix? What would you look at besides rod bearings and lifters?
Thanks
Last edited by Stude; Jun 3, 2012 at 06:26 PM.
Your gonna need to isolate this noise. Use a device to listen "into" the engine, such as a mechanics stethoscope, or a screwdriver with the handle end against your ear. Determine if it's top end or bottom. If its top, pull the valve covers. You will get a visual at that point, to determine if the lifters are up. Start it and observe. If its bottom end, pull it. Those ASA guys were hard on their stuff. I'm a NASCAR driver myself. Hope it works out for you.
Thread Starter
Teching In
Joined: Jun 2012
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Engine out, Nothing apparently hitting BUT for this:
The crankshaft position sensor has obviously gotten a little too cozy with the 24T reluctor wheel.
Will this cause the kind of knock heard in the video?
The crankshaft position sensor has obviously gotten a little too cozy with the 24T reluctor wheel.
Will this cause the kind of knock heard in the video?
