Engine knock, with video
08-26-2008, 02:00 AM
#1
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Engine knock, with video
New member here, own B-body LT1's but i thought i post this here also.
i took video of the knock on the 1995 Buick Roadmaster wagon i bought, take a look, what does this sound like to you?
http://www.youtube.com/watch?v=KQkCJ9e4O18
i took video of the knock on the 1995 Buick Roadmaster wagon i bought, take a look, what does this sound like to you?
http://www.youtube.com/watch?v=KQkCJ9e4O18
08-26-2008, 02:03 AM
#2
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here it is with the valve cover off
http://www.youtube.com/watch?v=o0lEBIcPy_A
that's not an illusion, the rocker does stop completely for a few seconds there and goes again.
would a seized lifter bounce up and down against the cam lobe and make that noise? took a couple of the lifters out and the plunger would NOT budge period, had to put it on a vise and put 80-90 lbt ft torque on it just to get it to move, but then you could push it down easy after that.
http://www.youtube.com/watch?v=o0lEBIcPy_A
that's not an illusion, the rocker does stop completely for a few seconds there and goes again.
would a seized lifter bounce up and down against the cam lobe and make that noise? took a couple of the lifters out and the plunger would NOT budge period, had to put it on a vise and put 80-90 lbt ft torque on it just to get it to move, but then you could push it down easy after that.
Last edited by v8killer; 08-26-2008 at 02:12 AM.
08-26-2008, 02:15 AM
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when compression test was done all cylinders were 173-175 except one that was 145, on the side where that noise is coming from.
I wasn't there when compression pressure test was done and can not trust anything that guy had to say,for all i know he didn't even do it. but assuming he was telling the truth, what sort of conclusion could be drawn from it?
I wasn't there when compression pressure test was done and can not trust anything that guy had to say,for all i know he didn't even do it. but assuming he was telling the truth, what sort of conclusion could be drawn from it?
08-26-2008, 09:49 AM
#9
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Yes it will. I recently spun a rod bearing and at first mine would only knock slightly around 2,000rpm. I was at the track when it happened and decided to chance it and drive home like that. 20 miles down the road it sounded like an old diesel knocking so hard. Honestly if you plan on going with a stock rebuild I would quit running it like that and start tearing down if you want to salvage as many parts as possible. All it takes is one start up to finally throw that rod into your block/head and ruin some things. Once again this based on the full belief that that is indeed rod knock which it sure does sound like. Drain your oil and cut your oil filter and half and with as bad as that knock is I would think you could see metal shavings and debris quite easily.
08-26-2008, 01:02 PM
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that was the first thing i checked when i got the car up here, wasn't that or a cracked flexplate.
Last edited by v8killer; 08-26-2008 at 02:37 PM.
08-26-2008, 01:03 PM
#12
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08-26-2008, 03:48 PM
#15
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To me the oil appears very black and fuel fouled. Something like that can easily take out a bearing. I think your best bet at this point is to atleast pull all the valvetrain, cam and lifters out (basically the top end). And look at them for damage. If nothing there I really feel you should start digging deeper. Hope this isn't a daily right now...