Rough Vacuum

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  #11  
Old 05-18-2009, 06:51 PM
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if u got flames then u got some lose spark coming from somewhere. bad wires, coil or dist cap. find a dark place or what till its really dark out and park in the darkest plac u can find and open the hood with the engine running. u should see were the spark is comming from. i did it once and it looked like a light show. almost every wire was lighting up. funny thing was it didnt run that bad. remember to be careful of the moving parts, because u cant see its easy to forget the fan or alternator is turning. with the vacumm leak u may be able to take a piece of paper or plasic and move it around on the motor while its running and see were it effects the noise, like wrap it around the fitting that u think is leaking and see if the noise is quiter. that may point u in the direction.
 
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Old 05-18-2009, 07:42 PM
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I went to the parts store i usually use for stuff i need sooner than later. And ordered a "ported vacuum switch". I had no idea that is what it was called so before now i didn't think they were made. So i ordered one that should fit my intake... Hopefully. Its supposed to be here tomorrow so ill change it out when i get home and hopefully that will take care of the problem. and if not, then it just saves me the embarressment of people asking me what kinda crap that is on my intake. And ill check the pcv valve in a bit and to check for arches anywhere.
 
  #13  
Old 05-18-2009, 07:43 PM
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Oh, and my dad said he is almost sure there is a skip in it. But this is pretty much the first old style car ive worked with. So i couldn't even tell, sadly enough.
 
  #14  
Old 05-18-2009, 08:11 PM
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Before we venture into this any farther... Where is the pcv hose supposed to be attached to. and where is the brake booster hose supposed to be?
 
  #15  
Old 05-18-2009, 09:53 PM
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Originally Posted by Orion
Before we venture into this any farther... Where is the pcv hose supposed to be attached to. and where is the brake booster hose supposed to be?
The PCV and brake booster can go on the large fitting at the base of the carb (if it has one) or on the manifold fitting. Doesn't matter which goes where, both ports are manifold vacuum sources.
 
  #16  
Old 05-18-2009, 10:06 PM
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u have a year im not familiar with. at that yr the pcv may be in the valve cover and hook to the carb/tb. the brake assist has always went to the intake manifold on any cars ive had but that does not mean its that way with all cars, my truck is assitsted by the power stearing.
 
  #17  
Old 05-19-2009, 01:04 PM
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The ported vacuum switch that i ordered has a thermostat opening, its not a regular vacuum port with threads on it you can screw into the intake, does anyone know a company i can order one like that off of, with just threads and 2 or 3 vacuum ports on it??
 
  #18  
Old 05-19-2009, 01:18 PM
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better hit some of the local wrecking yards and see what u can find.
 
  #19  
Old 05-19-2009, 04:05 PM
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I don't understand why you bought a ported vacuum switch when you're messing with the brake booster and PCV valve hookups?
For one, a vacuum switch would be used for feeding ported vacuum to the EGR valve until the engine heats up.
Also, the brake booster and PCV valve don't get vacuum from a ported source (a fitting on the carburetor above the throttle plates). You want manifold vacuum (at the intake manifold or a carburetor base fitting below the throttle plates).
 
  #20  
Old 05-19-2009, 04:47 PM
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This is what I need, http://www.yearone.com/serverfiles/f...ings&SM=1&SC=8 . The third one down on that list. What i have on there now is a home rigged cheesy version of that.

But from what everyone i talk to is telling me, because i do have a little bit of an upsized cam the vacuum will be lower, but I don't think it should be that low, and ive sprayed brake cleaner all around the vacuum port i have connected to the intake and the intake itself. so im stumped.

I also read that if the vacuum gauge is jumping a little bit at idle, if you give it gas and keep it there and the vacuum gauge needle starts to settle down and just stay still it has to do with the valve guides. But as far as i know the machine shop put new guides in them around 5 months ago when i had the motor rebuilt. So i don't believe it could be that.
 


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