I have recently installed the AIR system on my 1969 350 with a working AIR pump (&804199) and a correct Diverter Valve (29199) that I bought from someone that I trusted.

The seller seemed very knowledgeable and maybe my mistake was to not get any guarantees.

When I finally got around to installing the Pump, belt and diverter valve, I started the motor and found that all of the AIR was coming out of the muffler. After several rev tests, I found that all of the AIR still came out of the muffler.

Since I have never seen or really understood the function of this diverter valve, I took it off the elbow to looked inside to observe the operational mechanism.

I appears that there is a single valve the closes off the air passages to the exhaust manifold and based upon the connection of the vacuum hose, it appears that the closure would occur under high vacuum.

The diverter valve I had purchased for over $200 was stuck in the closed position that did not allow any air to the exhaust manifold. I guess I should have asked if it was tested before I purchased it. It would have been very easy to test this with a vacuum pump.

Luckily, the AIR pump that I have purchased (7804199) had a diverter valve (29190) that was attached to the pump that was almost identical to the 29199. I took this diverter valve off the elbow and observed that without any vacuum the valve was in the "OPEN" position that allows air to pass to the manifold and to the Diverter valve muffler. This diverter valve seems to function properly closing the valve to the exhaust manifold under high vacuum conditions.

As a result of this investigation, I have 2 questions:

1. If the single valve under normal conditions allows air to pass to the exhaust manifold and the Muffler, how does any air get to the exhaust manifold? Doesn't all of the AIR just go to the muffler?

2. Since the correct Diverter valve (29199) is stuck closed and does not appear to be holding a vacuum, who is the best person to perform a rebuild on this valve and how much does it cost?

Thanks for any help that you can give me!

I now understand why almost everyone removes these from almost every corvette I have ever seen!https://www.corvetteforum.com/forums...lies/crazy.gif

 

The valve opens in response to a vacuum signal received from the carb. If there's low or no vacuum, the air from the pump is directed out the muffler. If there's a higher level of vacuum- above the set point of the valve, the air is directed to the exhaust manifolds. There's no need or benefit in sending air to the exhaust manifolds in high vacuum situations. This in fact can cause afterfiring heard during trailing throttle.

I think Bill Hodel can rebuild these valves but many people inhibit the operation of the system by gutting the pumps and leaving the hardware there just for show or the smog inspectors.

 

Thanks for the information. I talked to Bill and he is very knowledgeable and willing to share information. It will be too costly for a rebuild at this time, so I will hold off on the Emissions project until I find a less costly alternative.

Thanks for your help..