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NEED HELP WITH THIS ENGINE NOISE

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Old Oct 18, 2003 | 11:14 PM
  #1  
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Default NEED HELP WITH THIS ENGINE NOISE

I have a loud clanging noise for about 3 seconds when I start the car and lately it would do it (intermittent) and lose power but recover. I put it up and went under to try and isolate where it was coming from. It appeared to be from the oil pan. I dropped the pan and took off the converter cover to inspect. Everything looked fine, except all 3 converter bolts were loose. That can account for the clanging noise, but could it be a cause for the intermittent roughness and loss of power? Maybe because of the external balance? Or could it be spun rod bearings? Can you visually see this condition without taking the rods out? There was nothing in the pan and no indications that anything was striking it from the inside, no dents, scratches or rubs. I rotated the engine while inspecting and everything looked fine. Tell me what you think it could be. :confused:
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Old Oct 18, 2003 | 11:31 PM
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Default Re: NEED HELP WITH THIS ENGINE NOISE (nastee383)

Get your self a mechanics stethoscope and touch the engine in the area where the noise is suspected it will be magnified. Old timers used to use a long screwdriver and can hear noise through the handle.
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Old Oct 19, 2003 | 07:34 AM
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Default Re: NEED HELP WITH THIS ENGINE NOISE (nastee383)

ttt, it was a late post. Still need opinions. Thanks
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Old Oct 19, 2003 | 08:35 AM
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Default Re: NEED HELP WITH THIS ENGINE NOISE (nastee383)

What do you mean by "converter" bolts?
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Old Oct 19, 2003 | 08:44 AM
  #5  
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Default Re: NEED HELP WITH THIS ENGINE NOISE (paul67)

What do you mean by "converter" bolts?
The 3 bolts that attach the torque converter to the flex plate.
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Old Oct 19, 2003 | 11:59 AM
  #6  
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Default Re: NEED HELP WITH THIS ENGINE NOISE (nastee383)

I was thinking cat con for some reason. They do rattle when worn out. As does the heatshield above it. The stethoscope (or bamboo stick) is good advice for pinpointing the source.
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Old Oct 19, 2003 | 12:25 PM
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Default Re: NEED HELP WITH THIS ENGINE NOISE (nastee383)

kinda sounds like a broken flex plate - hope not - dave
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Old Oct 19, 2003 | 06:49 PM
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Default Re: NEED HELP WITH THIS ENGINE NOISE (nastee383)

You probably found the problem already with the loose bolts. If you weren't loosing oil pressure, the bearings are likely fine too. Check the flexplate for cracks, then fire it back up to see what's up after the bolts are tight. Of course, you could always yank the 383, freshen it, put it in the Blazer, build a 540 for the Vette, bolt on a big nasty blower... :crazy:
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Old Oct 19, 2003 | 09:41 PM
  #9  
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Default Re: NEED HELP WITH THIS ENGINE NOISE (dually4wd)

You probably found the problem already with the loose bolts. If you weren't loosing oil pressure, the bearings are likely fine too. Check the flexplate for cracks, then fire it back up to see what's up after the bolts are tight. Of course, you could always yank the 383, freshen it, put it in the Blazer, build a 540 for the Vette, bolt on a big nasty blower... :crazy:
Hopefully that'll be the case. Oil pressure was good as always. I'll tighten/loctite those bolts and check closely for any cracks. Actually I was getting excited about the possibility of getting a 427SB shortblock. I guess the worst part now will be getting the oil pan back on without it leaking! I think I'll try one of those one-piece pan gaskets. Thanks :thumbs:
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