Jeep CJ 1945-1970 Repair Information

Air Cleaner



To service the oil bath type air cleaner on the L4-134, F4-134, 6-226 or 6-230, first unscrew the oil cup clamp and remove the oil cup from the cleaner body. Remove the oil from the cup and scrape out all the dirt inside, on the bottom. Wash the cup with a safe solvent. Refill the oil cup and replace it on the air cleaner body. Use the same viscosity of oil as you use in the engine crankcase.

To service the air cleaner body (less the oil cup), loosen the hose clamp and remove the hose form the cleaner. Detach the breather hose from the fitting on the cleaner. Remove the two wing nuts and lift the cleaner from the vehicle. Agitate the cleaner body thoroughly in a cleaning solution to clean the filtering element and then dry the element with compressed air. Reinstall the air cleaner body and replace the oil cup. The air cleaner should be serviced every 2,000 miles.

To service the oil bath type air cleaner on V6 engines, first remove the air cleaner from the engine by unscrewing the wing nut on top of the air cleaner. Remove the oil cup from the body of the air cleaner and remove all of the oil from the oil cup. Remove all of the dirt from the inside of the coil cup with a safe solvent. Wash the filter element in solvent, air dry it, and then fill the oil cup to the indicated level with clean oil. Assemble the air cleaner element to the oil cup, making sure that the gasket is in place between the two pieces. Mount the air cleaner assembly in the carburetor, making sure that the gasket between the air cleaner and the carburetor is in place and making a good seal. Secure the air cleaner to the carburetor with the wing nut.


Remove the wing nut or hex nuts on top of the cover. On the 6-225, detach the rubber hose from the engine rocker arm (valve) cover and set the cover aside, being careful not to damage the large diameter hose or hoses to the air cleaner inlet.

If the filter element has a foam wrapper, remove the wrapper and wash it in detergent or a safe solvent. Squeeze and blot dry. Wet the wrapper in engine oil and squeeze it tightly in an absorbent towel or rag to remove the excess.

Clean the dirt from the paper element by rapping it gently against a flat surface. Replace the element as necessary.

Clean the housing and the cover. Replace the oiled wrapper, if any, on the element and reinstall the element in the housing, placing it 180 degrees from its original position.

The oiled foam wrapper element is a factory option for some years. It should be available through Jeep parts. There are also aftermarket variations on this, both dry and oiled.