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If belts are too tight, unnecessary stresses are placed upon the pulley bearings and belts which might shorten the life of both
1. Inspect the condition and adjustment of alternator belts and fan drive belts. 2. To check the belt tension, apply 25 lbs 110 N of force midway between the
pulleys. Correctly adjusted belts will deflect 12 to 34 inch 13 to 19 mm.
1. Adjust Alternator Belts
1. To adjust the alternator drive belts, loosen mounting bolts 1 and adjusting bracket nuts 2.
2. Adjust the alternator in or out by either tightening or loosening adjusting nuts 2, as required, to obtain the correct adjustment.
3. Tighten bolts 1 and nuts 2. 4. If new belts are installed, check belt adjustment again after 30 minutes of engine
operation. Replace belts in matched sets only.
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NOTE: If only one belt of a matched set is replaced, it will carry more of a load than the belts not replaced since the older belts are stretched. The additional load on the new belt
could cause it to break.
2. Adjust Fan Drive Belts
1. To adjust the fan drive belts, loosen mounting bolts and adjust with adjusting bolt. 2. Move the fan drive up or down as required to obtain the correct adjustment. Tighten
mounting bolts.
3. If new belts are installed, check belt adjustment again after 30 minutes of engine operation.
HOSES AND CLAMPS
1. InspectReplace
Hose replacement prior to failure is a cost effective preventive maintenance practice. Replacing a hose before it fails saves money and reduces the chances for unscheduled
downtime. By replacing a hose that is cracked, soft or leaking, you will avoid major repairs that could result in a severe engine overheating problem.
Inspect all hoses for leaks due to cracking, softness and loose clamps. Replace hoses that are cracked or soft, or 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. NOTE: For constant torque hose clamps, see the Torque Specifications section in this
publication.
After Replacing Hoses 1. Add coolant mixture to the cooling system. Bring it to the proper level by mixing a
solution of acceptable water and Caterpillar Antifreeze. Test for supplemental additive concentration. Add proper amount, or if equipped with a coolant additive
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element, install the appropriate element ONLY if using another type of antifreeze. 2. Install the filler cap.
3. Start the engine and inspect for leaks. 4. Check water temperature gauge for proper operating temperature.
ALR-TO-AIR AFTERCOOLER SYSTEM
1. Caterpillar discourages the use of winter fronts or other air flow restriction devices mounted in front of radiators with air-to-air aftercooled engines. Air flow restriction
can cause higher exhaust temperatures, power loss, excessive fan usage and a reduction in fuel economy.
2. A slight reduction in power or response, or a small increase in exhaust temperature, may indicate a small air leak in the charge air cooler core or piping.
3. An aftercooler hose, gasket or duct failure, or significant system leak will cause a large drop in boost pressure and power. The engine can be operated at this power
level long enough to reach a safe stop or repair area. Sustained operation under this condition should be avoided.
Inspect Check
Inspect all air ducting and gasket connections at each oil change. Constant torque hose clamps should be used to secure the ducting. Tighten these clamps until the spring is at
least partially compressed. Check with your OEM manufacturer or the Torque Specifications section of this manual for the appropriate torque specifications.
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PM LEVEL 2
You must read and understand the warnings and instructions contained in the Safety section of this manual, before performing any operation or maintenance procedures.
All PM Level 2 maintenance is to be performed at the intervals specified in the Maintenance Management Schedule for the power rating of the engine being
maintained.
Before proceeding with PM Level 2 maintenance, perform all PM Level 1 and Daily maintenance requirements.
1. Engine
