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Discussion Starter #1
will it only pull vacum at full rpms?when i start it ,it stays at 0 when i rev it up a little it moves and bounces a little.is it better to take the line off the valve cover when warming up the motor?
 

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will it only pull vacum at full rpms?when i start it ,it stays at 0 when i rev it up a little it moves and bounces a little.is it better to take the line off the valve cover when warming up the motor?
should pull vacuum at idle
 

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B1 Racing
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With everything set up right you should see a few inches at idle. You might have a leak or the pump speed is too low??? I used to have my data logger hooked up to the engine reading vac. I was pulling about 12 inches at the end of a run back then but it didnt go straight to 12 it takes a little while to pump down to 12. I think I saw 3-4 at idle.
 

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Discussion Starter #5
how long does it take at at idle to see vacum?i started it ,but it was only for about 10 seconds.
 

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how long does it take at at idle to see vacum?i started it ,but it was only for about 10 seconds.
i was thinking about this. if your engine isn't sealed up good and tight (oil pan and valve cover gaskets especially) that might be a reason for it not pulling vacuum. Did you say you blew the dipstick out last time we were at the river? might be your leak right there.
 

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i was thinking about this. if your engine isn't sealed up good and tight (oil pan and valve cover gaskets especially) that might be a reason for it not pulling vacuum. Did you say you blew the dipstick out last time we were at the river? might be your leak right there.

If the pumps not working properly do you think that would of caused the dip stick to push out?
 

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mo balls than $cents$
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slip a longstyle plug boot over the dipstick to seal it off;)
 

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Just a thought here, it could be plumbed with the lines backwards. it would then push into the engine.
 

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Discussion Starter #12
i was thinking about this. if your engine isn't sealed up good and tight (oil pan and valve cover gaskets especially) that might be a reason for it not pulling vacuum. Did you say you blew the dipstick out last time we were at the river? might be your leak right there.
the dip stick is pretty tight.when i started it,i had the relieve valve adjusted almost all the way out.
 

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its plumbed just like yours.
Gotcha. Why are you starting it up with the releif valve open? Just letting the oil warm up before it starts to draw? I warm mine with the belt off if it's sat for a long time, but then it should be good to go. Where are you reading your vacuum from? The opposite valve cover?
 

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Discussion Starter #15
Gotcha. Why are you starting it up with the releif valve open? Just letting the oil warm up before it starts to draw? I warm mine with the belt off if it's sat for a long time, but then it should be good to go. Where are you reading your vacuum from? The opposite valve cover?
that is where it was set out of the box.reading from oppisite valve cover on the back.mounted a guage in the dash so i could watch vacum all the time.
 
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