Fan Shroud Sticker

This partially sandblasted sticker was on my fan shroud. I have not seen a similar sticker on this web site. If this from an aftermarket shroud or different vehicle?

Apologies for being upside down!

 

Looks like it is a California emissions thing.

 

Yes, way back when, early CA vehicles had to have NOX devices. Essentially it's a thermal valve installed in a radiator hose that interrupts your vacuum advance. All in the interest of lowering combustion chamber pressures and attending NOX emissions.
As pre-75 vehicles are not tested in CA now, the device is no longer needed.

Gosh this brings back memories of the bad old days.

 

The above sticker indicates that a Kar Kit was installed on the vehicle. These were not Jeep factory components, but aftermarket kits made by Air Quality Products which were approved for use by the State of California. I found a manual online for the Kar Kit that explains what it does (or hopefully, did....as in past tense).

Note especially #1 below - I put it in bold:


Kar Kit Emission Control System for 1955-65/1966/70 Vehicles
Air Quality Products, Inc. 1976
Orange, CA 92668

The retarded spark timing approach used by Kar Kit controls emissions solely by retarding engine spark advance and carburetor adjustment.
Kar Kit, and all State of California Air Resources Board-approved used vehicle exhaust emission control systems, uses retarded spark timing techniques. Retarded spark control systems are also used on many new vehicles. The various devices either completely or partially disconnect the vacuum advance mechanism, and some systems also retard the vehicle’s base timing for further control. Also, the systems include specific procedures for carburetor idle speed and mixture adjustment. Kar Kit is not recommended for vehicles with impaired or defective cooling systems.

All spark retard systems have the common disadvantage of reduced gas mileage and somewhat higher engine operating temperatures. However, gas mileage reduction is generally very small due to the carburetor adjustments which tend to offset this reduction. Retarding the spark timing means that the spark plug fires at a later time in the compression stroke of the engine. Retarded spark timing is accomplished with Kar Kit by (1) disconnecting the vacuum to a mechanism which causes the plugs to fire earlier under certain operating conditions; and (2) adjusting the basic spark timing to a later setting on most engines.

Retarding the spark timing can reduce the formation of oxides of nitrogen (NOx) by 40% to 50%. The effects of retarded spark timing on your engine result from the fact that gasoline is burned less efficiently in the cylinders. This can cause an increase in gas consumption, less in the city and more on the highways. Part of the increased gas consumed is burned while the gases are being exhausted from the engine, rather than on the power stroke, thus increasing the average temperature of the exhaust gases. The effects of hotter exhaust gases on your engine depend upon the engine design, and the condition of the cooling and lubrication systems. In some engines, more heat will be transferred into the cooling system. In other engines, the heat load on the cooling system may remain the same. The installation of the Kar Kit emission control system include an inspection of the cooling system and the recommended repair of defects because we can not identify the specific engines which cause added cooling system heat load. This maintenance, however, is a good idea, regardless. Test data show that leakage and poor maintenance of cooling systems are far greater problems during periods of hot weather than small increases in coolant temperatures from retarded spark timing.

Exhaust system components of all engines will operate hotter with retarded spark timing, including the exhaust valves, the exhaust manifold, and the exhaust pipes. Possible problems from hotter exhaust manifolds and exhaust pipes can be avoided by checking to see if there is sufficient clearance between these exhaust parts and other parts of the vehicle. This inspection is part of the Kar Kit emission control system.

Engine exhaust gas temperatures normally increase with greater speed and load. These increases, however, are generally greater with spark retard. On later models (1966-1970), the state requires that approved devices which use a significant amount of spark retard include a means for reducing the temperatures above 60MPH. Most approved systems (both new and used car) include an electrical or mechanical switch which restores normal timing at the higher speeds, thus reducing the temperatures. The Kar Kit 1966-1970 (NOx) approved device is designed as a simple low cost system and is recommended only for limited duty vehicles which are not operated at high speed. Therefore the system does not include the expensive switches necessary to restore timing at high speeds. The Kar Kit includes a decal which is affixed to the speedometer to remind the owner not to operate the vehicle for sustained periods above 60MPH.

Installation instructions:
The Kar Kit installation includes several steps which must be followed. They include cooling system inspection, distributor advance check, de-activation of vacuum spark advance, and readjustment of basic timing, carburetor mixture and idle speed to Kar Kit specifications.

Kar Kit use limitations:
The Kar Kit is a low cost NOx control system, designed for limited duty vehicles, and the following use limitations are to be observed. If these installation or operating limitations conflict with your vehicle condition, configuration or operating requirements, DO NOT INSTALL Kar Kit.

• • 1. DO NOT OPERATE vehicles equipped with Kar Kit at sustained speeds above 60MPH (short periods of emergency and passing are OK). Installation of Kar Kit on vehicles which operate a major part of the time at either sustained high speed or have load conditions (such as towing a trailer) is not recommended.
  • 2. DO NOT INSTALL on engines engines less than 50 cubic inches or on engines with distributors without centrifugal or vacuum advance.[/font]
  • 3. DO NOT INSTALL on Volkswagen or Porsche.
  • 4. DO NOT INSTALL on engines with impaired or defective cooling systems.

Step 1) Inspection & maintenance of the cooling system
Step 2) Distributor check
Step 3) Disconnection of vacuum advance
Step 4) Ignition Timing Check and Adjustment (1966-1970)
Adjust timing at an idle speed recommended by the engine manufacturer. Set at 1° BTC on all engines except those where the manufacturer’s specified setting is:

• More retarded than 1° BTC – then set at the manufacturer’s specified setting for these engines
• More advanced than 7.5° BTC – then set at 1/2 of the manufacturer’s specified setting for these engines.

Step 5) Adjustment of Carburetor (1966-1970)
Adjust the carburetor idle speed and idle mixture in accordance with the manufacturer’s specifications.
Step 6) Exhaust system inspection
Inspect clearance between the exhaust system and any point on the chassis. Adjust if clearance is less than 1/2”.
Step 7) Documentation
Affix “limited use” decal to face of speedometer.
Install Tune-Up instruction decal within engine compartment in conspicuous location.
If the vacuum advance unit on your distributor has a hose connected to the engine, you no longer have the Kar Kit installed. If the vacuum advance unit is not connected (hose is plugged), then the Kar Kit is still installed.

 

Man oh man, does all that bring back bad car memories of the seventies. Those NOx devices really sucked monkey butt.

 

Vacuum from engine is still connected to the distributer vacuum advance, so the Kar Kit and the sticker are both gone. Thanks for all the info and history on this.

 

What a great post Maury! Thank you for sharing with us