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Help! Can hear knocking...

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Old Jan 6, 2006 | 10:45 PM
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Default Help! Can hear knocking...

I was showing my friends the 'vette today and had the hood opened, when i heard some unusual sounds coming from the passenger-side valve covers. Sounds like knocking? Kind of? Not as loud as I would expect it to be, but still scary. I've never had the valve covers off, and I haven't gotten my hands dirty with the engine yet because I was afraid that I would break something. Well it sounds like something broke anyways, so I want to fix it. Suggestions? I have a new oil pan gasket that I need to put in too, so whatever I do I will do at the same time as the gasket. Thanks!
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Old Jan 7, 2006 | 12:34 AM
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Well, it depends on what the knock sounds like and when it does it. I don't know how much experience you have. If it has a low tone like a thump, it might be bottom end. If it has a high tone like a tick, it's probably top end. Gosh, I've had water pumps make an engine sound like it was going to come apart.
If you don't have any experience, I'd recommend taking it to an honest and reputable mechanic. You mentioned the oil pan gasket, was it ever run out of oil? So much of troubleshooting is tactile in nature, it's almost impossible to say without being there.
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Old Jan 7, 2006 | 12:51 AM
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lol well i think that it's gotta be the top end, because it's only coming from the passenger side. it's just kind of like something is tapping in there i guess, and it was doing it at idle. the oil never got too low i don't think..... might have been a quart and a half low.
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Old Jan 7, 2006 | 01:14 AM
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If no smoke, it is most likely that you just need to adjust the rockers. To find it, with valve cover off and engine running and warm, push down hard on the end of each rocker with the tip of a large flat screwdriver. Whichever one goes quiet when you do this is the culprit. Be aware that you and your engine will get oil all over though. It could also be a weak lifter.
If smoke is coming from the right side tail pipe or oil is coming out of the dipstick tube, you have more serious problems.

Last edited by 79ls1; Jan 7, 2006 at 01:17 AM.
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Old Jan 7, 2006 | 12:08 PM
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Originally Posted by 76mike
I was showing my friends the 'vette today and had the hood opened, when i heard some unusual sounds coming from the passenger-side valve covers. Sounds like knocking? Kind of? Not as loud as I would expect it to be, but still scary. I've never had the valve covers off, and I haven't gotten my hands dirty with the engine yet because I was afraid that I would break something. Well it sounds like something broke anyways, so I want to fix it. Suggestions? I have a new oil pan gasket that I need to put in too, so whatever I do I will do at the same time as the gasket. Thanks!
check the fuel pump. when they start to go it can sound like a bottom end knocking. and passengers side like you say i will bet thats the problem
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