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The chart below shows the most common questions asked by owners of Detroit Diesel® engines 4-71 Natural 2 Valve when trying to troubleshoot why their engines underperform. It categorizes areas of possible malfunction, likely cause and recommended action to bring your new, rebuilt or used Detroit Diesel® engine back to proper operation. The chart will give you confidence when speaking with your Detroit Diesel® engine mechanic or ordering parts. As a quick reference guide only, the chart must not be thought of as a substitute for the use of your Detroit Diesel® engine 4-71 Natural 2 Valve Owner's operating or service manual. PROBLEM POSSIBLE REASON CHECK
The Detroit 471 engine will last you for many hours with proper maintenance and care. Diesel Pro can help. We have the right supplies to keep these engines running, year after year. Our parts are made out of high quality materials, and guaranteed to last. That is why we offer a one year warranty on our new parts, so you can shop with confidence. We also have a large and diverse inventory of products, including our popular overhaul kit that can get an older engine back to performing like it was new. We also offer the 471 service manual to help you tackle big projects, an essential for any Diesel mechanic, whether you work on engines full time, or have to make the occasional repair. Unsure which part you need? If you have any other questions, need help finding a part, or to place an order, give us a call at 888-433-4735 and we would be happy to help. 
Engine will not start
Lack of air intake or restricted air intake
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Broken blower shaft
Worn out blower shaft
Defective fuel pump
Defective starter
Discharged battery
High exhaust back pressure
Black smoke coming out of engine
Defective injector
Contaminated fuel
Broken or worn cylinder parts
Engine overloaded
Faulty intercooler or aftercooler (for turbo engines only)
White smoke coming out of engine
Broken piston ring
Incorrectly installed ring set
Defective injector
Fuel quality or grade
Long idle periods
Broken or bent push rod
Injector or governor improperly adjusted
Low engine oil pressure
Water in engine oil pan
Fuel in engine oil pan
Defective oil cooler
Engine overloaded
Crankcase overfilled
Low engine RPM
Improperly working injector
Governor calibration
Hi engine RPM
Governor calibration
Engine overheating
Defective fresh water pump
Defective raw water pump (marine engines only)
Defective thermostat or thermostat seal
Clogged radiator or heat exchanger (marine engine only)
Grey smoke coming out of engine
Long idle periods
Defective intercooler or aftercooler (for turbo engine only)
Restricted air intake
Defective injector
Contaminated fuel
Blower or turbocharger seals leaking
Geartrain makes noises
Low oil level
Engine driven accesories
Damage main or rod bearing
Detroit Diesel 4-71 Usefull Information
All engines in this series will have a serial number that start with 4A (For example, 4A-12345.) Older engines may have a serial number that starts with 471 (For example, 471-RA63.) The model number, which is an eight digit code, will start with 704, and an example would be 7042-7201.
General Information
This Detroit 471 engine is a two-cycle, 4 cylinder engine with a displacement 284 cubic inches and 5 main bearings.
Normal oil capacity is between 15 to 20 quarts. The oil filter should be changed every 100 hours. The oil should be changed every 100 hours as well, for new engines, though this can be gradually increased. For vehicle use, this translates to every 1000 to 3000 miles, with highway use needing less frequent changes than consistent stop and go conditions.
This engine can be referred to by different names, such as GM 471 or 4-71 Detroit Diesel.
Horsepower and Torque
The information below is based on brake horsepower, and a 471T generator set.
Standby: 180 BHP at 1500 RPM, 210 BHP at 1800 RPM.
Prime: 164 BHP at 1500 RPM, 191 BHP at 1800 RPM.
The information below is for marine pleasurecraft, with N80 injectors. The horsepower is measured as shaft-horsepower. Performance is with paragon 2:1 gear and 12 volt, 25 amp generator.
SHP (Power propeller load): 25 at 1200 RPM, 35 at 1400 RPM, 75 at 1800 RPM, 105 AT 2000 RPM, and a maximum of 160 at 2300.
Fuel Consumption (with propeller) is 2.5 gallons per hour at 1400 RPM, 5 gallons per hour at 1800 RPM and 9 gallons per hour at 2200 RPM.
Other Popular Categories
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