75. DESCRIPTION.

a. Intake System. The air intake system consists of oil bath air cleaner, connecting air hose, and carburetor intake hose fitting. This system is located on left side of vehicle.

b. Exhaust System. The exhaust system consists of muffler and tailpiece assembly, front exhaust pipe assembly, and rear exhaust pipe. Exhaust pipe ends are a slip fit in cylinder exhaust ports.

76. AIR CLEANER (figs. 46 and 47).

a. General. Air cleaner should not be submerged in water, nor should high‐pressure stream be directed into cleaner louvers (where air enters on rear of body) when cleaning vehicle. Either water or dirt entering air cleaner in excessive quantities will raise the oil level in oil cup and choke off proper air supply to carburetor.

b. Service. With vehicle in normal use on hard‐surfaced roads, clean and refill air cleaner oil cup with engine oil (seasonal grade) at least each time engine oil tank is drained and refilled. CAUTION: Service more frequently under dusty conditions; daily under extremely dusty conditions. Check oil supply daily.

(1) Hold oil cup with one hand and release (unlatch) oil cup retaining spring clips to remove oil cup.

(2) If oil in cup is clean, with no signs of dirt and grit in oil or cup, but the oil level is below the indicated level mark, add engine oil (seasonal grade) to bring level up to mark. NOTE: If oil and cup are dirty, empty out oil and wash out cup with dry‐cleaning solvent. Refill with clean engine oil (seasonal grade) to indicated level mark.

(3) Before installing oil cup make sure that the oil cup gasket is in place and in good condition.

(4) Check baffle plate thumb screw for tightness.

c. Maintenance (fig. 47). The rectangular‐type oil bath air cleaner is provided with two filter elements, retained in filter body by means of the baffle plate. If daily check reveals excessive accumulation of dirt and grit in oil and cup, filter elements must be removed and cleaned. NOTE: Check several times daily under extremely dusty or sandy conditions.

(1) Hold oil cup with one hand and release (unlatch) oil cup retaining spring clips; remove cup.

(2) Unscrew baffle plate thumb screw and remove baffle plate.

(3) Filter elements may “bind” in cleaner body. If so, rap side of body with hand to loosen them; or, if necessary, withdraw elements from body with pliers or a hooked wire.

(4) Check for presence and condition of gasket above the two filter elements (in filter body); also for oil cup gasket.

(5) Clean both filter elements thoroughly in dry‐cleaning solvent. Allow elements to dry out (use air hose if available).

(6) Clean oil cup and refill to indicated level mark. Use clean engine oil (seasonal grade).

(7) Dip one screen surface of each filter element about ½ inch into oil in the oil cup (to “oil wet” filter pack). Install the two filter elements, baffle plate, and oil cup immediately after “oil wetting” the filter elements. Make sure gaskets are in place. NOTE: Do not add more oil to oil cup after elements have been dipped into it, because excess oil absorbed by elements will drip back into oil cup, bringing level back to normal.

(8) Round‐type oil bath air cleaner used on earlier models does not have removable filter element. Complete cleaner body must be removed from vehicle, immersed and agitated in cleaning solvent to wash out dirt. After cleaning, allow filter element to dry (use air hose if available), then apply a few squirts of engine oil to inside of cleaner element, using oilcan. Refill cup, replace baffle plate and cup, securely tightening clamp band thumb screw.

77. HOSE AND CARBURETOR FITTING.

a. Remove. Carburetor intake and hose connection must be removed from carburetor to remove and/or install air hose.

(1) Loosen screws in the two hose clamps.

(2) Remove four screws retaining carburetor air intake fitting. Remove carburetor fitting from end of hose, and pull hose off air cleaner body connection.

b. Install. Before installing air hose, inspect for breaks or faulty condition that might prevent airtight seal between air cleaner and carburetor fitting.

(1) Install one end of hose on carburetor fitting. Do not tighten clamp screw.

(2) Install other end of hose on air cleaner connection. Do not tighten clamp screw.

(3) Install carburetor fitting. Securely tighten the four screws. Next, center air hose between carburetor fitting and air cleaner connection and securely tighten hose clamp screws.

78. REMOVE AIR CLEANER.

a. Loosen hose clamp screw at air cleaner body connection and remove two nuts and gear‐toothed washers from bolts securing air cleaner assembly to frame bracket. NOTE: Gear‐toothed lock washers are also used under heads of the two mounting bolts. Withdraw cleaner from end of air hose.

b. The same procedure applies to round‐type air cleaners used on earlier models.

79. INSTALL AIR CLEANER.

a. Engage air cleaner hose connection in end of hose and mount cleaner assembly on frame bracket with two bolts, gear‐toothed lock washers, and nuts. Securely tighten mounting nuts. NOTE: The plated (whitened) mounting bolts, four gear‐toothed lock washers, and bolt nuts must effect a ground connection between bracket and filter mounting to insure adequate radio bonding. Tighten air hose clamp screw at cleaner body connection.

b. The same procedure applies to round‐type air cleaners used on earlier models.

80. REPLACEMENT OF AIR CLEANER MOUNTING BRACKET.

a. Air cleaner mounting bracket and air cleaner can be removed or installed as an assembly.

b. Remove.

(1) Loosen hose clamp connection at air cleaner body.

(2) Disconnect battery ground wire. This prevents shorting battery when removing cleaner bracket clamp bolt.

(3) Remove the two upper cleaner bracket frame clamp bolts.

(4) Remove lower mounting bolt. Cleaner lower bracket mounting and clutch cable tube mounting are secured to frame bracket by the same whitened radio bonding bolt, gear‐toothed lock washers, and nut. Remove nut and drop bolt to free cleaner bracket.

c. Install.

(1) Engage air hose and cleaner body connection.

(2) Attach lower bracket first. Locate cleaner bracket so that hole lines up with bolt holes in frame bracket and clutch cable tube mounting. Pass whitened radio bonding bolt upward through bracket hole, install shakeproof lock washer, and securely tighten nut.

(3) Attach bracket to the two upper frame clips. Tighten the clamp bolt nuts.

(4) Connect battery ground wire.

(5) Tighten air hose clamp screw at cleaner connection.

81. EXHAUST SYSTEM.

a. Remove Muffler Assembly.

(1) Support vehicle on rear stand.

(2) Remove bolt from end of hanger bracket on left side of vehicle, and remove bolt from muffler clamp and skid plate bracket on right side of vehicle. Drop skid plate.

(3) Loosen nut and bolt on clamp which secures front end of muffler at exhaust pipe connection (clamp is attached to muffler).

(4) Remove muffler rear hanger bracket bolt nut. Pull muffler assembly free from exhaust pipe connection.

b. Install Muffler Assembly.

(1) Engage muffler pipe and exhaust pipe at muffler pipe clamp connection. Do not tighten clamp bolt nut as yet.

(2) Attach muffler rear hanger bracket to frame bracket bolt, installing lock washer, and tightening nut. NOTE: It may be advisable to loosen hanger bracket on muffler so that muffler can be lined up for front end connection.

(3) Tighten muffler and exhaust pipe clamp bolt nut and rear hanger nut.

(4) Raise skid plate into position and install right side mounting bolt which secures muffler front bracket and skid plate bracket to frame clip. Tighten all mounting nuts.

c. Remove Exhaust Pipes.

(1) Refer to step a (1), (2), (3) above.

(2) Remove right side footboard and brake pedal assembly as follows: Loosen footboard rear support stud nut, remove front support stud nut, and pull footboard outward to free end of safety guard. Remove bolt which secures front exhaust pipe clamp, and remove nut from rear support rod, freeing stop light switch and rear end of footboard sidebar. Remove nut from front support rod, and drop footboard and brake foot pedal assembly to provide clearance for exhaust pipe removal. Disengage rear exhaust pipe at cylinder port, at same time prying and pulling front exhaust pipe forward and downward to free from cylinder port. Both exhaust pipes can now be worked downward and removed from vehicle as an assembly.

d. Install Exhaust Pipes.

(1) Position exhaust pipe (front and rear) assembly, working it into position so that front pipe end slips into cylinder port; then, pry and force rear pipe end into rear cylinder port.

(2) Mount footboard, brake foot pedal, and sidebar assembly on support rods, installing washer and nut on front support rod.

(3) Position and mount stop light switch on rear support rod. See that spring and operating control wire exert a straight pull on switch plunger when foot pedal is operated.

(4) Install bolt, washer, and nut which secure front exhaust pipe clamp to footboard sidebar.

(5) To attach safety guard to sidebar, pull front end of footboard away from sidebar, line up holes in sidebar and safety guard end, then pass footboard support stud through both pieces, and secure with washer and nut.

(6) Tighten footboard rear support stud nut.

(7) To complete installation, follow procedure outlined in step b (1) through (4) above.