Smog Pump

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Nissan A.I.S. (Air Injection System) with air pump system -- a.k.a. "smog pump" -- was first fitted to some 1960s Datsuns. The first B-series models to have an Air Pump was the North American B210 series for 1975.

NOTE: No Datsun 1200 was fitted with an air pump.

Overview

An engine driven pump, about the size of the alternator, forces air into the exhaust passages. This allows any unburnt gasoline to burn up in the exhaust system, thus reducing pollution.

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Components:

• Air pump
• Air pump air cleaner. This is large disk mounted down by the Charcoal Canister
• Check valve before going into head. Prevents exhaust from backflowing into pump or air filter
• A.B. Valve (anti-backfire valve) between Air Cleaner and intake port (port on intake manifold). This valve has a single vacuum hose to control it. It prevents backfires in the exhaust system when during acceleration the richer naturally becomes richer, a condition the Throttle Opener also works on. However unlike the throttle opener, it dumps air into directly the intake manifold, causing it to lean out. This only occurs during decceleration so does not lean out the mixture when accelerating or cruising.

California models had these additions to prevent overheating of catalytic convertor:

• Air control valve
• E.A.R.V. (Emergency air relief valve)

or (later models):

• C.A.C. valve. One hose tees into the pump output, the other hose dumps to the air (apparently not connected to anything). This valve has a single vacuum hose to control it

Layout

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1976 B210 USA Federal 4-speed. WIDE bracket contains tensioner and supports the pump
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1979 B310 USA Federal 4-speed. NARROW bracket contains tensioner and supports the pump
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Crankshaft#Pulley. Outer groove is for the air pump V-belt
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B210

B210 USA 1975-1978
* 1975 model year started September 1974
* 1974 did not use a smog pump
* 5-speed cars (FU) did not use a smog-pump, but used a passive Air Induction System

COMMON PARTS
14800-H7206 ASSY-AIR PUMP WITH PULLEY <> 14800-H7205
 * pulley differs slightly between H7205 & H7206
14815-H7200 ASSY-IDLER PULLEY AIR PUMP
14816-H7202 BRACKET-IDLER PULLEY AIR PUMP
14853-H7201 BELT-AIR PUMP (1006 M/M)

FEDERAL 
14842-U6004 Air Pump bracket
lower bracket

CALIFORNIA
14840-H7205 BRAKET-AIR PUMP [lower bracket]
14832-H7360 COMBINED AIR CONTROL VALVE (CAC VALVE) 0876-0777 [1977 model year]
14832-H7361 COMBINED AIR CONTROL VALVE (CAC VALVE) 0877-     [1978 model year]