Air Injection Pipe

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Mar 23, 2010 | 09:14 PM

JohnBOV43159

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From: Riverside, CA

Air Injection Pipe

Today I noticed a hole had rotted through the check valve part on my intake manifold air injection check valve. This is the pipe that comes up out of the intake manifold just behind the thermostat, makes a little bend up to the valve and then a hose runs out of the valve and down to the smog pump. Its a 1977 351M. I grabbed the valve and it completely broke off of the pipe. I am assuming that I probably have some vacuum problems at the least.

What does this valve do? Can I just plug it off at the manifold? The smog pump doesn't even have a belt on it so I don't care about making any of the smog stuff work, just want the truck to run its best.

Mar 23, 2010 | 11:11 PM

JohnBOV43159

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From: Riverside, CA

I tried to start the truck with the injection pipe from the intake manifold open, valve broken off and hose unattached, truck wouldn't start and smoke billowed out of the carb.

I just attached the hose coming up from the air/smog pump to the pipe where the valve broke off and the truck started ok. What's going on?

Mar 24, 2010 | 04:04 PM

JohnBOV43159

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From: Riverside, CA

Guess I'm just talking to myself but today I took all the smog crap off the truck and put a 3/4" aluminum pipe plug I got fro the hotrod shop into the Edlebrock intake manifold and the truck runs 100% better than it ever has.