Thread: catalytic air pumps

Air pumps for catalytic Heat exchangers. Air pumps are absolutely nessesary because the driven air blows across the coils to heat the catalytic converter. Testing the air pump is easy with a normal gauge we all use. Lift should be around 7-8 hg normally I would have to double check. The air pump is an important and overlooked part on a truckmount with a catalytic converter heat exchanger..

Ara, I was just pondering this issue last night. I was under the impression that the Air Injector pumps were installed on cars in the '70's as test fooling equipment to reduce the exhaust CO2 output PPM. In other words, the Air Injector pumps diluted the exhaust gas by mixing it with air so the engines would meet the government EPA emission regulations. I think my ’73 Chevelle is the oldest car I remember having an air pump.

I have never measured the exhaust gas pressure in an exhaust manifold. I imagine the exhaust gas pulses in the exhaust pipe are well over 8 hg. Adding fresh compressed air to the exhaust stream would actually reduce the exhaust gas temperature as it crosses the catalytic in the HX. So the Air Pump would prevent the catalytic from overheating?

The statements above are rambling thoughts and are not to be misconstrued as based in any factual reference, Analyze at your own peril.

Originally Posted by Newman

Ara, I was just pondering this issue last night. I was under the impression that the Air Injector pumps were installed on cars in the '70's as test fooling equipment to reduce the exhaust CO2 output PPM. In other words, the Air Injector pumps diluted the exhaust gas by mixing it with air so the engines would meet the government EPA emission regulations. I think my ’73 Chevelle is the oldest car I remember having an air pump.

I have never measured the exhaust gas pressure in an exhaust manifold. I imagine the exhaust gas pulses in the exhaust pipe are well over 8 hg. Adding fresh compressed air to the exhaust stream would actually reduce the exhaust gas temperature as it crosses the catalytic in the HX. So the Air Pump would prevent the catalytic from overheating?

The statements above are rambling thoughts and are not to be misconstrued as based in any factual reference, Analyze at your own peril.

Chris, good questions. In reference to your question about cooling and fooling the exhaust with the air pump. Air or oxygen is considered an accelerant when we are dealing with flames. The introduced air actually increases the temperature,and provides a more complete burn while reducing emission and carbon. A truckmount that runs too long without the airpump for the catalytic will definitely have more carbon build-up.

"I imagine the exhaust gas pulses in the exhaust pipe are well over 8 hg." Chris I am not sure what you mean by this but I am sure the exhaust is measured in pressure rather than vacuum. If you are referencing my comment on 8 hg on the airpump itself. The air pump actually pulls vacuum that can be tested to ensure the part is not faulty. I hope I made this clear and I apologize for any misunderstandings.