Smog Pumps on 1986 K20 Suburban

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militaryjeep

militaryjeep

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Location
chatsworth
First Name
steve
Truck Year
1986
Truck Model
Suburban K20
Engine Size
5.7
1986 K20 Suburban
Federal spec, no Cats / Dual Smog pumps / EGR / Quadrajet Carb (ALL STOCK)
Stainless factory exhaust manifolds

I have a Fed spec K20 with the dual smog pumps, EGR and Air injection.
The only thing the smog pumps do is shoot air into the manifold tubes
just down stream of the head.
I was changing belts and was unable to get the smog pump belt so I just
left it off as an experiment.
First driving impression was absolutely no difference in drivability or performance.
Any comments as to the long term effects of leaving the pumps disconnected?
Will it affect the temp of the manifolds or the EGR function in any negative way?

Looking for thoughts from the gallery....
 
C

CountKrunk

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Count
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1984
Truck Model
C20 Custom Deluxe 3+3
Engine Size
v8 350
My truck has a smog pump and all the other stock stuff. Smog pump has been beltless for ??? Years. I've put a thousand miles on it no issues.
 
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1STLS1

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MIchael
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1985
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K10
Engine Size
350
AIR pumps just continue the combustion once outside the cylinder. They also promote the catalytic converter lighting off and doing what it supposed to do.
\
In your situation, you will see an increase in start up emissions. The exhaust will run cooler, the EGR should be drawn from the cast passage in the heads and intake so don't see an issue there

Eventually, the pump may seizes, the vanes will get stuck to the walls of the housing and may require replacement if you need to make it work again.
 
fast 99

fast 99

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350
No you won't notice any difference in power provided it isn't a feedback system [O2 sensor]. I question why take any of it off? What are you attempting to accomplish? And yes a stationary pump will seize in a relatively short time and without air circulating the control valves may burn up. Have also seen injection tubes inside the manifold melt without air to cool them. Air pumps hurt nothing with regard to power or drivability.
 
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