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vacuum created by engine, is this good?

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R

recordsj

Jedi Warrior
Offline
1500 mg midget

I noticed that my engine is creating a vacuum. I can feel the vacuum when a place my figer over the dipstick tube.
Is this good?
Can someone explain to me what is causing this?
And tell me how it can be fixed it if something wrong is causing this?
 
some vacum is good. Likely what your feeling is a good thing. Unless its so much it actualy sucks oil mist from the crankcase your in good shape. It keeps everything sealed up. Helps restrain oil leaks too!
 
no, if you have no white smoke on decel or downshifting (Large vacum) your okay. Mine actually whistles lightly for a second threw the dipstick tube when shut down. I seen a few do it. That means things are sealed up pretty good. High HP race cars actually run specail high vacum pumps to help seal up the rings. What is making you curious is there a problem your trying to diagnos or just something you noticed?
 
If I could piggy back off this thread a bit; if I wanted to introduce a little vacuum into the rocker cover, on a Weber set up, what's the easiest way to do that? Drill a little hole in the intake manifold below the carb, run a little line into the existing rocker cover breather hose (currently running to air filter housing)?
 
you can go ahead and piggy back... i got the info i needed.

question... I didn't think the weber carb produces much of a vacuum, I may be wrong though... are you trying to induce a vacuum in the rocker cover to help eliminate some leaks?
 
jvandyke said:
If I could piggy back off this thread a bit; if I wanted to introduce a little vacuum into the rocker cover, on a Weber set up, what's the easiest way to do that? Drill a little hole in the intake manifold below the carb, run a little line into the existing rocker cover breather hose (currently running to air filter housing)?
Click to expand...

a good amount of vacum could be introduced with a bit of customizing. Drill a hole in the air filter backing plate and bend a piece tubing inward just above the carb throat opening. (On the primary) than hook up you howe. Should give you just about the right amount. You may be able to tack weld the tube or even use a rubber grommet and a clamp of sorts. seen it done easily with a copable copper tube and a conduit clamp. The key is to try and get the inside of the tube in the intake flow of aire entering the carb.
 
I do have the customary hose from rocker to air filter housing, just enters the housing right smack under the foam element, maybe this is good enough and I'm making trouble out of nothing?
 

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I drilled and tapped a hole just below the carb on the outside of the manifold and then hooked up a vacuum gauge and got what I think is the right amount of vaccum by sizing the screw in hose port. I ran that port to the timing chain cover vent and then the one from the valve cover to the hole in the breather. The breqther hole alone is not enough with the DGV with my experience. All the fords had a plate between the carb and intake with a port in it.
 
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