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Discussion Starter · #1 ·
Hi All
Where does one get replacement parts for the pollution stuff namely the diverter valve mine is causing backfire on deceleration and I cant seem to locate a source for one ? 1980 CJ-7 258
TIA

Learn to let go of what does not serve you ,but forces you to serve it
 

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You can also try your local Ford store, or look at some early Fords in the junk yards. They use the valves for their thermactor systems. There were some "high altitude" part numbers as back firing was common on these systems above 6,000 feet.

 

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Early 70's GM air pumps used vacuum actuated diverter valves ....... in fact if you accidentally pulled off the vacuum line you'd blow off the exhaust. ....... well if it was old enough.
GeeAea

 

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Diverter valve help

My diverter valve has a "T" on it that used to go to my old air cleaner and BBD carb. I have since swapped out the BBD for an MC2100 and capped the T. Was this wrong? Is this "T" on the diverter a vent that must be opened or connected to something?
 

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Discussion Starter · #6 ·
My diverter valve has a "T" on it that used to go to my old air cleaner and BBD carb. I have since swapped out the BBD for an MC2100 and capped the T. Was this wrong? Is this "T" on the diverter a vent that must be opened or connected to something?
My diverter valve has a "T" on it that used to go to my old air cleaner and BBD carb. I have since swapped out the BBD for an MC2100 and capped the T. Was this wrong? Is this "T" on the diverter a vent that must be opened or connected to something?
I am not sure what year jeep or size (# of cylinders) you have. Diverter valves usually involved an Air pump, pumping a low pressure air, Through the diverter valve into a manifold that went into your Exhaust manifold.
The purpose was to Add air to the Exhaust gasses so they could be processed, burned up in the catalytic converter, more efficiently.
However when you take your foot off the gas peddle (Decelerate) you are pumping a greater percentage, by volume of raw gas into your exhaust gasses. By adding air to that raw gas and exposing it to the temps of the exhaust system it tends to cause a backfire situation.
So the diverter valve diverts the air supply momentarily so it doesn't backfire. It is activated by a vacuum line usually going to your carb.

There were two different diverter valves made to my knowledge, one that activated off ported vacuum the other worked off manifold vacuum. One involved Computer activation of the vacuum switches mounted on the firewall. the other just activated by Manifold vacuum and was used up till 1980 or whenever they went over to the computer .

Unless you had the pulseair system that drew air from inside the aircleaner?
That system I don't know much about. except it eliminated the air pump and had Two lines going out of the air-cleaner directly to the exhaust system.
 
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