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#1
08-12-2022, 11:53 AM
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Found the problem
Popping in the exhaust. #1 compression was 15 psi down.
I just touched the pieces and they came away.
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Frank M. 75 Firebird 68 Firebird 400 RAIII 66 Chevy II 461 Pontiac in AZ |
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#2
08-12-2022, 12:14 PM
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Something fall into the carb? Do you know the source of the foreign material?
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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
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#3
08-12-2022, 12:38 PM
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What got in there?
Is it magnetic?
__________________
I do stuff for reasons. |
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#4
08-12-2022, 03:47 PM
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I believe I am diligent about small parts around the carb when the air cleaner is off. Perhaps not as it looks like something small did get in. The pieces are magnetic. Whatever it was might have broken up with most of it leaving with the exhaust. The pieces were embedded but came away when I barely touched them.
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Frank M. 75 Firebird 68 Firebird 400 RAIII 66 Chevy II 461 Pontiac in AZ |
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#5
08-12-2022, 06:01 PM
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I had that happen once
on a 20 ' glasply it was a center chunk of the throttle shaft that busted loose between the screws on the reman q jet looked very similiar |
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#6
08-12-2022, 06:47 PM
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Did that with an aircleaner wingnut..........it was not pretty.
george
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"...out to my ol'55, I pulled away slowly, feeling so holy, god knows i was feeling alive"....written by Tom Wait from the Eagles' Live From The Forum |
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#7
08-12-2022, 07:07 PM
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93 Lumina Euro 3.4L DOHC 4-valve. Cylinder 2 clearly got screwed, but I have no idea when, and after replacing the head gaskets for unrelated problems, the engine ran great.
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#8
08-13-2022, 12:27 AM
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Smooth the sharpness down on the piston and head and she will be OK!. Sharp edged create hot spots and unless you running the jagged edge of compression, Which I think unlikely. a smooth over to knock the sharps off and life will be good
__________________
Dan Pesonen  "If it ain't broke, modify somethin till it is" |
| The Following User Says Thank You to zippy For This Useful Post: | ||
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#9
08-13-2022, 06:36 AM
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While you have it down that far I would pull the valves out of that chamber and confirm that neither Intake or exh valve sealing areas have been nicked up or scratched.
You can even first just pour rubbing Alcohol in each port and see if it weeps out. Otherwise you will be tearing it all down again possibly. If you feel lucky want to play the odds then clean things up, bolt the head on with the new gasket, set the valvetrain in place for that cylinder and do a compression test with no valley pan or intake bolted on. While your at it look close for scratched and nicks on the bore walls.
__________________
I do stuff for reasons. |
| The Following User Says Thank You to 25stevem For This Useful Post: | ||
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