The Caterpillar CM20-6 is a 56 L engine. It powers generator sets from Caterpillar, including the CM20.
Also known as: Caterpillar CM20-6
Part of the Caterpillar CM20 engine family — 3 variants share parts & fitment.
| Displacement | 56.0 L |
|---|
| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Engine oil (S-O-S oil sample) | Test | 125 hr | Severe service occurs at high loads, in high temperatures, and in dusty conditions | |
| Coolant (S-O-S coolant analysis Level 1) | Test | 250 hr | Cat ELC - Every 250 Hours; also the recommended sampling interval for all conventional heavy-duty coolant/antifreeze and for commercial coolants that meet Cat EC-1 | |
| Engine crankcase oil (S-O-S oil sample) | Test | 250 hr | Table 6 S-O-S Oil Sampling Interval; severe applications may require a more frequent oil sampling interval | |
| SCA (Supplemental Coolant Additive) concentration | Test | 250 hr | Test the concentration of SCA or submit a coolant sample at 250 hour intervals or at PM Level 1 intervals; check at every oil change or every 250 hours, whichever occurs first | |
| Coolant (S-O-S coolant analysis Level 2) | Test | 500 hr | 12 mo | First service — For new systems, refilled systems, and converted systems that use Cat ELC or Cat DEAC; also every year; use the interval that occurs first |
| Cat ELC Extender addition (cooling system) | Other | 6000 hr | Treat the cooling system with Cat ELC Extender at 6000 hours or one half of the coolant service life | |
| Coolant (Cat ELC) | Change | 12000 hr | 12000 service hours or six years; use the interval that occurs first | |
| Coolant (S-O-S coolant analysis Level 1 and Level 2) | Test | 12 mo | Cat DEAC - Yearly |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Other | Gross Input Torque (TH55-E70) | 12 667 | N•m (9350 lb-ft) | |
| Other | Gross Input Torque (TH55-E90) | 12 677 | N•m (9350 lb-ft) | |
| Other | Rating condition (diesel 7 L and higher) | 99 kPa (29.31 in Hg) dry barometer, 25°C (77°F) | SAE J1995 inlet air standard | |
| Other | Rating condition (diesel up to 6.6 L) | 100 kPa (29.5 in Hg) total barometric pressure, 1 kPa (.295 in Hg) vapor pressure, 25°C (77°F) | ISO/TR14396 inlet air standard | |
| Other | Rating condition (gas) | 100 kPa (29.61 in Hg) and 25°C (77°F) | SAE J1349 standard | |
| Other | Stall Torque Ratio (TH55-E70) | 2.23 | ||
| Other | Stall Torque Ratio (TH55-E90) | 2.23 | ||
| Pressure | WS255 pump plunger load | 238,000 | lb (107,960 kg) | |
| Pressure | WS273XD pump plunger load | 275,000 | lb (124 738 kg) | |
| Pressure | WS305XD pump plunger load | 250,000 | lb (113 398 kg) | |
| Speed | Maximum Input Speed (TH55-E70/TH55-E90 transmissions) | 1970 | rpm | |
| Speed | Rated Input Speed (TH55-E70/TH55-E90 transmissions) | 1900 | rpm |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Coolant | Cat DEAC (Diesel Engine Antifreeze/Coolant) | Acceptable coolant; commercial heavy-duty antifreeze/coolant must meet ASTM D4985 or ASTM D6210 | Conventional heavy-duty coolant/antifreeze. Caterpillar recommends a 1:1 mixture of water and glycol. Do not use a commercial coolant/antifreeze that only meets the ASTM D3306 specification. Do not use Cat SCA at the initial fill when Cat DEAC is used. | ||
| Coolant | Cat ELC (Extended Life Coolant) | Caterpillar EC-1 specification (preferred); also meets ASTM D4985, ASTM D6210, and ASTM D3306 | Service life of 12000 service hours or six years. Premixed ELC provides freeze protection to -37 C (-34 F); ELC Concentrate can be used to lower the freezing point to -52 C (-62 F). An Extender is the only additional maintenance needed at 6000 service hours or one half of the ELC service life. Cat ELC cooling systems can withstand contamination to a maximum of ten percent of conventional heavy-duty coolant/antifreeze and/or SCA. | ||
| Coolant | Cat SCA (Supplemental Coolant Additive) with water | SCA concentration in a cooling system that uses SCA and water should be six to eight percent by volume; do not exceed the eight percent maximum concentration. If Cat SCA is not used, the commercial SCA must provide a minimum of 2400 mg/L or 2400 ppm (140 grains/US gal) of nitrites in the final coolant mixture when used with water, and a minimum of 1400 mg/L or 1400 ppm (82 grains/US gal) with heavy-duty coolant/antifreeze. | |||
| Coolant | Glycol (ethylene glycol / propylene glycol) | Propylene glycol coolant must meet ASTM D6210-04 | Ethylene glycol: 50 percent = freeze protection -37 C (-34 F), boil protection 106 C (223 F); 60 percent = -52 C (-62 F), 111 C (232 F). Propylene glycol: 50 percent = -32 C (-26 F), 106 C (223 F). Do not use propylene glycol in concentrations that exceed 50 percent; do not use ethylene glycol in concentrations that exceed 60 percent. All Caterpillar diesel engines equipped with air-to-air aftercooling (ATAAC) require a minimum of 30 percent glycol. | ||
| Engine oil | Cat DEO (Diesel Engine Oil) 10W-30 and 15W-40 | Cat ECF-1 (exceeds); API CI-4, API CI-4 PLUS, API CH-4, API CG-4, API CF (Cat DEO SAE 15W-40) | Caterpillar oils are used to fill diesel engines at the factory. Non-Caterpillar commercial oils are second choice oils. Do not use API CF-4 oils in Caterpillar diesel engines. Do not use single grade API CF oils or multigrade API CF oils in 3500 Series, C175 Series and smaller DI diesel engines. | ||
| Engine oil | Commercial oils (DI engines) | Cat ECF-1 required; API CG-4 multigrade acceptable; API CH-4, API CI-4 and API CI-4 PLUS acceptable only if the requirements of Cat ECF-1 are met; do not use API CF-4 oils | Minimum TBN must be 10 times the fuel sulfur level (ASTM D2896); minimum TBN of the oil is 5 regardless of a low fuel sulfur level. API CG-4 oils: do not exceed the standard oil drain interval. | ||
| Engine oil | Commercial oils (PC engines) | Cat ECF-1; API CH-4, API CI-4, API CI-4 PLUS (if Cat ECF-1 requirements met); API CG-4 multigrade; API CF-4 multigrade; API CF | Minimum TBN of the oil that is used in PC engines must be 20 times the fuel sulfur level; minimum TBN of new oil is five. Change the oil when the TBN deteriorates to 50 percent of the original TBN. | ||
| Engine oil | Re-refined base stock oils | Acceptable if they meet the performance requirements specified by Caterpillar; filtering is inadequate for producing high quality re-refined base stock oils. | |||
| Engine oil | Synthetic base stock oils | Acceptable if they meet the performance requirements specified for the engine compartment. Caterpillar does not recommend the automatic extension of oil drain intervals for any type of oil. | |||
| Engine oil | SAE 0W-20 | -40°C to 10°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | SAE 0W-30 | -40°C to 30°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | SAE 0W-40 | -40°C to 40°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | SAE 5W-30 | -30°C to 30°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | SAE 5W-40 | -30°C to 50°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | SAE 10W-30 | -18°C to 40°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines); SAE 10W-30 is the preferred viscosity grade for the 3116, 3126, C7, C-9 and C9 diesel engines between -18 C (0 F) and 40 C (104 F) | ||
| Engine oil | SAE 10W-40 | -18°C to 50°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | SAE 15W-40 | -9°C to 50°C | Table 1 Lubricant Viscosities for Ambient Temperatures (DI diesel engines) | ||
| Engine oil | Cat SAEO SAE 30 | API CF-4 category | 0°C to 40°C | Table 2 - 3116 and 3126 Marine Engines with mechanical unit injection; factory fill has API CF-4 category and viscosity grade of SAE 30 | |
| Engine oil | SAE 30 | 0°C to 40°C | Table 3 Lubricant Viscosities for Ambient Temperatures - PC engines only | ||
| Engine oil | Cat SAEO SAE 40 | API CF-4 category | 5°C to 50°C | Table 2 - 3116 and 3126 Marine Engines with mechanical unit injection. Caterpillar does not recommend the use of multigrade oils in the 3116 and 3126 Marine Diesel Engines that use mechanical unit injection. | |
| Engine oil | SAE 40 | 5°C to 50°C | Table 3 Lubricant Viscosities for Ambient Temperatures - PC engines only | ||
| Fuel | 35° API gravity, LHV 42 780 kJ/kg (18,390 btu/lb) | SAE J1995 | Diesel engines 7 liter and higher; used at 29°C (84.2°F) with density 838.9 g/L | ||
| Fuel | Biodiesel blends | Caterpillar biodiesel specification, ASTM D6751, or EN 14214 | May be blended in amounts up to a maximum of 30 percent (models C6.6, C7, C9, C11, C13, C15, C18, C27, C32, 3114, 3116, 3126, 3176, 3196, 3208, 3306, C-9, C-10, C-12, 3406, C-15, C-16, C-18, 3456, 3408, 3412, 3500 Series, C175 Series, 3600 Series, C280 Series, CM20, CM25 and CM32); for 3003 through 3034, 3046, 3054, 3056, 3064, and 3066 engines, maximum ratio of 5% biodiesel to 95% acceptable diesel fuel. Caterpillar recommends a maximum of one year for fuel storage. | ||
| Fuel | EPA 2D 89.330-96 | EPA 2D 89.330-96 | Diesel engines up to 6.6 liter; density 0.845-0.850 kg/L @ 15°C (59°F); fuel inlet temperature 40°C (104°F) | ||
| Fuel | JP-5, JP-8, Jet A-1 | MIL-DTL-5624U, MIL-DTL-83133E, ASTM D1655-05 | Table 8 - may be used in extreme cold ambient conditions down to -54 C (-65 F); these fuels typically do NOT meet ULSD fuel requirements; if viscosity is below 1.4 cSt at 40 C (104 F) use the fuel only in temperatures below 0 C (32 F); do not use any fuels with a viscosity of less than 1.2 cSt at 40 C (104 F). | ||
| Fuel | No. 1-D / No. 2-D distillate diesel fuel | ASTM D975; Caterpillar Specification for Distillate Diesel Fuel (Table 7) | Cetane number 40 minimum (DI engines) or 35 minimum (PC engines); aromatics 35% maximum; ash 0.02% maximum (weight); carbon residue on 10% bottoms 0.35% maximum (weight); copper strip corrosion No. 3 maximum; distillation 10% at 282 C (540 F) maximum, 90% at 360 C (680 F) maximum; flash point legal limit minimum; pour point 6 C (10 F) minimum below ambient temperature; sulfur 0.1% maximum; kinematic viscosity 1.4 cSt minimum and 20.0 cSt maximum as delivered to the fuel injection pumps; water and sediment 0.1% maximum; water 0.1% maximum; sediment 0.05% maximum; gums and resins 10 mg per 100 mL maximum; lubricity 0.52 mm (0.0205 inch) maximum at 60 C (140 F) by ASTM D6079; cloud point must not exceed the lowest expected ambient temperature. | ||
| Fuel | Ultra Low Sulfur Diesel (ULSD) | ASTM D5453, ASTM D2622, or DIN 51400; <15 ppm (0.0015%) sulfur | In North America, diesel fuel identified as "ASTM D975 Grade No. 1-D S15" or "ASTM D975 Grade No. 2-D S15" meeting "ASTM D975 Thermal Stability Guideline X2.10.2.2" generally meets the Caterpillar requirements for ULSD fuel. | ||
| Fuel | dry natural gas, LHV 35.54 MJ/Nm3 (905 btu/ft3) | Gas ratings based on SAE J1349 standard conditions of 100 kPa (29.61 in Hg) and 25°C (77°F) | |||
| Gear oil | Cat TDTO (Transmission/Drive Train Oil) | Caterpillar TO-4 oil specification | Table 4 - SAE 30: -15 C (5 F) to 80 C (176 F); SAE 50: -5 C (23 F) to 95 C (203 F). Formulated for transmissions and drive trains only and should not be used in engines. Cat GO (Gear Oil) is not the same as Cat TDTO and does not meet Caterpillar's specifications for TO-4 oil. | ||
| Grease | Cat Advanced 3Moly Grease (NLGI grade 2) | NLGI certification of "GC-LB"; petroleum base oil and lithium complex thickener; 3 percent molybdenum disulfide | Optimum temperature range -18 C (0 F) to +80 C (+140 F). Molybdenum has a median particle size of 3 microns. |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
⚠ Do not leave an empty SCA maintenance element on a system that is filled with ELC. The element housing may corrode and leak causing an engine failure.
⚠ Improper or incomplete rinsing of the cooling system can result in damage to copper and other metal components.
⚠ The cooling system cleaner must be thoroughly flushed from the cooling system. Cooling system cleaner that is left in the system will contaminate the coolant. The cleaner may also corrode the cooling system.
Tools: Caterpillar cleaner for cooling systems, 5P-3413 Pipe Sealant, Suitable containers to collect fluids
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
The Caterpillar CM20-6 has a displacement of 56.0 liters.
The Caterpillar CM20-6 powers 1 generator set(s), including Caterpillar CM20.