vacuum jumping

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May 18, 2013 | 02:58 PM

palazzopl

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From: Boynton Beach Florida

vacuum jumping

my 81 vacuum at idle jumps from 17 to 20. I just had the heads done and i'm wondering if I set the valves to tight. Any other causes for vacuum problem.

May 18, 2013 | 05:33 PM

scottyp99

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From: Oxford MA-----You just lost the game!!!!

Here's a good article on how to use a vacuum gauge to diagnose an engine. Pay particular attention to scenarios 5, 8, and 15, in your case. Good luck,

http://www.secondchancegarage.com/public/186.cfm

Scott

May 18, 2013 | 05:43 PM

cardo0

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From: Las Vegas - Just stop perpetuating myths please.

Varying vacuum is indication of a bad/leaking valve.

Does it vary at higher rpm?

cardo0

May 19, 2013 | 10:02 AM

palazzopl

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From: Boynton Beach Florida

Quote:

Originally Posted by cardo0

Varying vacuum is indication of a bad/leaking valve.

Does it vary at higher rpm?

cardo0

at high rpm its ok .and I also have a hesatation when I accelerate. I have a can af sea foam I'll try to day. If no help I'll remove the covers and take a look

May 25, 2013 | 10:03 AM

palazzopl

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poured a half a can of sea foam down the carb and the rest in the gas tank. I let it sit for a few days then took it for a short ride. Everything seams to be ok now.