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Old 06-11-2014, 12:45 PM   #1
Gruman
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What does this do?

What is this vacuum pot for? Its attached to the intake manifold and the tube that comes out the top is not connected to anything else.

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Old 06-11-2014, 12:55 PM   #2
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Re: What does this do?

That is an egr valve. You don't need it. You can replace it with a block off plate or better yet get an aftermarket intake.
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Old 06-11-2014, 12:57 PM   #3
Gruman
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Re: What does this do?

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Originally Posted by junksaver View Post
That is an egr valve. You don't need it. You can replace it with a block off plate or better yet get an aftermarket intake.
Getting another intake will probably happen eventually. Do I need to cap it off if I cant find a block off plate or will it even matter?

Thanks!
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Old 06-11-2014, 01:03 PM   #4
In The Ten Ring
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Re: What does this do?

I had to look it up! "Inert gas replaces a portion of the combustable mixture in the cylinders." So....in other words...you get to lose power. No, you do not need this!
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Old 06-11-2014, 01:05 PM   #5
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Re: What does this do?

Exhaust gas recirculation valve. I introduces a varied amount of exhaust into the intake during certain engine loads and conditions. It's an emissions device that helps fuel burn more completely and efficiently by introducing a stable medium (exhaust) into the intake. It basically has the effect of reducing engine head temps and by extension the chances of detonation.

Most cars before the late sixties didn't have them, and they're really not necessary if your motor is well tuned.
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Old 06-11-2014, 04:08 PM   #6
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Re: What does this do?

Like others have said, it's the exhaust gas recirculation valve. It was installed on engines starting in 1973. It meters a small amount of exhaust gas (water and CO2) back into the intake manifold to cool off the combustion process. This reduces the chance of oxygen and nitrogen combining.

If you have no drivability concerns you can leave it alone. It's not hooked up.
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Old 06-11-2014, 04:19 PM   #7
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Re: What does this do?

Thanks Everyone! It kills me sometimes not to know what something does under my hood. Not being a gearhead most of my life, I'm kind of green when it comes to stuff like this.

Like this... No clue what this is either... (on the fender well)
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Old 06-11-2014, 04:19 PM   #8
truckster
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Re: What does this do?

Quote:
Originally Posted by Gruman View Post
Getting another intake will probably happen eventually. Do I need to cap it off if I cant find a block off plate or will it even matter?

Thanks!
If you remove it, you need to block it off. However, just leaving it in place will have the same result. It's normally closed; vacuum pulls it open, so if no vacuum is attached, it will stay closed. Carbon tends to build up on them over time, so it may not be completely closed, but it should still be OK just to leave it.
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Old 06-11-2014, 04:30 PM   #9
michael bustamante
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Re: What does this do?

Fender thing looks to be aftermarket maybe? I noticed two different kinds of mounting bolts
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Old 06-11-2014, 04:53 PM   #10
Gruman
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Re: What does this do?

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Originally Posted by michael bustamante View Post
Fender thing looks to be aftermarket maybe? I noticed two different kinds of mounting bolts
Lots of things going on with this... The original motor is gone, at one point looked to have an aftermarket A/C installed. (still have the condenser in front of the radiator) Then I think the motor got swapped with an 81 model, aftermarket A/C scrapped and original compressor brackets retained on the 81 motor. (without the compressor)

Also might be why I have an EGR thing on my manifold...
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