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Old 08-31-2003, 07:42 PM   #1
My Boy's Toy
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Vacuum ?

The vacuum on my rebuilt 275Hp 327 fluctuates between 6 & 9 Hg. . Cant find any vacuum leaks , Any Ideas ?
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Old 08-31-2003, 08:28 PM   #2
JimKshortstep4x4
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Smile

If you have ruled out the carb and vacuum leaks, and the engine has new plugs, etc., I would try reseting the valves. Even though it is messy, I prefer setting them hot with the engine running. I use tabs on the rockers and a cut-off valve cover to minimize the oil splashing, loosen the nuts until the rockers click. Tighten the nut until the noise goes away and tighten an additional 1/4-1/2 turn.

If that does not help, I would check the compression and go from there.

Jim
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Old 08-31-2003, 08:40 PM   #3
My Boy's Toy
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Set the valves at 1/2 Turn , new plugs , pulled the plugs & there still running rich , have the carb leaned out one turn from seated.
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Old 08-31-2003, 10:29 PM   #4
Longhorn Man
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Depending on your cam specs, that may be all the vac you can get out of it.
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Old 08-31-2003, 11:05 PM   #5
My Boy's Toy
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I'm running a 272 Energizer Cam , & I have a Fluctuating Hg. Reading , so i'm thinking i have a leak somewere?
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Old 09-01-2003, 08:35 AM   #6
Huck
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I would bet a vacuum leak around the intake or one of the ports/hoses. Block off all hoses and use a short length of garden hose and listen as you move that hose all over the top of the engine. You may find that leak.
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Old 09-01-2003, 09:05 AM   #7
jay6891
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I have never tryed the garden hose route. I always use carb cleaner and spray around intake, carb, vacuum lines, and if engine speeds up you found your leak. Timing right, I maybe wrong but if it is retarded it with show low vacuum.
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