156640-0621 ZEXEL 9 423 618 536 BOSCH DAMPER 9423618536 1566400621 me738921

Crankcase Breather
Clean
This maintenance is to be performed every other oil change or 600 hours. 1. Loosen hose clamp (1) and remove the hose from the cover.2. Loosen three breather cover bolts (2) and remove cover (3). 3. Remove breather element (4), and wash in clean, nonflammable solvent and allow to dry. 4. Install clean, dry breather element (4).5. Install cover (3) and bolts (2).5. Install hose and clamp (1). Tighten clamp (1) to 27 4.5 lb in (3.0 0.5 N m). Refer to topic Torque Specifications for the proper torque of hose clamp-worm drive band type. If the crankcase breather is not maintained on a regular basis, it will become plugged. A plugged crankcase breather would result in excessive crankcase pressure that may cause crankshaft seal leakage.Refer to the Torque Specifications section of this manual for Torque for Standard Hose Clamps-Worm Drive Band Type hose clamps if your engine is equipped.Alternator, Fan and Accessory Drive Belts
Inspect/Replace
Inspect the condition and adjustment of alternator belts and fan drive belts.Inspect all drive belts for wear and replace if they show any signs of wear.If one belt in a set requires replacement, always install a new matched set of belts. Never replace just the worn belt. If only the worn belt is replaced, the new belt will carry all the load, as it will not be stretched as much as the older belts. All the belts will fail in rapid succession.Belt Adjustment
If belts are too loose, they vibrate enough to cause unnecessary wear on the belts and pulleys.If belts are too tight, unnecessary stresses are placed upon the pulley bearings and belts which might shorten the life of both.The engine is equipped with an automatic belt tensioner, adjustments should not be necessary.To check the belt tension if NOT equipped with an automatic belt tensioner, refer to the vehicle manufacturer's recommendations. Correctly adjusted belts will deflect approximately 3/8 to 5/8 inch (9 to 15 mm).Hoses and Clamps
Inspect
* Inspect all hoses for leaks due to cracking, softness and loose clamps.* Replace hoses that are cracked or soft and tighten loose clamps.Before Replacing Hoses
1. After engine is cool, loosen the radiator filler cap slowly to relieve any pressure and remove the cap.2. Drain the coolant from the cooling system to a level below the hose being replaced.3. Remove the hose clamps, disconnect the old hose and replace with a new hose.4. Install hose clamps. (See the Torque for Standard Hose Clamps-Worm Band Type chart in the Torque Specifications section of this publication for the appropriate torque value.) For constant torque hose clamps, also refer to the Torque Specifications section in this publication.After Replacing Hoses
Refer to Cooling System Specifications in this publication and/or consult your Caterpillar dealer for more detailed specifications.5. Add coolant water mixture to the cooling system. Fill to the proper level by mixing a solution of acceptable water and Caterpillar Antifreeze. Test for supplemental additive (Conditioner) concentration. Add proper amount, or if equipped with a coolant additive element, install the appropriate