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#1
08-05-2022, 08:22 PM
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Flat lobe
What are the symptoms of a cam lobe that has gone flat? My friends 400 according to him "is not firing on 2 cylinders". I will go tomorrow and do a compression test.
Last edited by 68WarDog; 08-05-2022 at 08:30 PM. |
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#2
08-05-2022, 08:34 PM
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Loose pushrod, sometimes the pushrod gets bent as well, then the rocker comes off the top.
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73 T/A 455, 4speed |
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#3
08-05-2022, 08:55 PM
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Loose Rocker arm. Exhaust popping back thru carb. Dry mouth yet Sweaty steering wheel grip.
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#4
08-05-2022, 08:56 PM
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Quote:
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#5
08-06-2022, 05:44 AM
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Unlikely you'll have a "flat lobe" with a roller cam. When things go bad there it's a DISASTER with lots of broken/bent parts and "trash" everyplace.
Check the simple things first if it's not making a bunch of noise. Plugs, wires, compression, vacuum leaks, or failed intake gaskets...
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#6
08-06-2022, 06:16 AM
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If it’s two cylinders right next to each other, then my moneys on a blown head gasket.
When this takes place and you only read a little compression on each cylinder then what you do to confirm that it’s a blown head gasket is remove either plug and do another test. In doing that you will find that you now have zip for compression.
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