The R-5227170 is a very common and critical fuel injector used in a wide range of Detroit Diesel engines, particularly in the Series 60 (12.7L and 14L) and some DD15 engines. It's a precision component that plays a huge role in engine performance, fuel economy, and emissions.

Here’s a comprehensive breakdown of everything you need to know about the R-5227170 Diesel Fuel Injector.

Core Specifications & Application

• Part Number: R-5227170 (This is the Detroit Diesel OEM number).

• Common Aftermarket/Cross References: Denso 095000-7741, Bosch 0445110375. Many reputable remanufacturers will use this base number.

• Engine Applications (Primary):

• Detroit Diesel Series 60: 12.7L (Most common application)

• Detroit Diesel Series 60: 14L

• Detroit Diesel DD15 (Early models, often replaced by updated part numbers).

• Vehicle Applications: This injector is found in thousands of:

• Class 8 Trucks (Freightliner, Western Star, Volvo, Mack with Detroit engines)

• Motor Coaches & Buses

• Power Generation & Industrial Units

Key Features & Technology

This is an Electronically Controlled Unit Injector (EUI). It combines the injection pump and injector nozzle into a single unit, located in the cylinder head.

• Solenoid-Operated: The ECM sends a high-voltage signal to the solenoid, precisely controlling injection timing and duration.

• High Pressure: It generates extremely high injection pressures (upwards of 30,000 psi) for optimal fuel atomization.

• Critical for Emissions: Proper functioning is essential for meeting EPA emissions standards (especially for 2004-2007 engines).

Common Symptoms of a Failing R-5227170 Injector

If you're researching this part, you might be troubleshooting. Look for:

1. Hard Starting or No Start: Especially when cold.

2. Misfire/Rough Idle: Engine runs unevenly; you can often identify the bad cylinder by "cutting out" injectors one at a time.

3. Loss of Power: Engine feels sluggish, lacks power under load.

4. Excessive Black or White Smoke:

• Black Smoke: Unburned fuel due to poor atomization or incorrect timing.

• White Smoke: Raw fuel passing through the cylinder unburned.

5. Increased Fuel Consumption: A leaking or inefficient injector dumps fuel without producing power.

6. Engine Knock or "Tick": A louder-than-normal clicking sound from one cylinder.

7. Fuel in Engine Oil: A leaking injector tip or seal can dilute engine oil, raising the oil level and degrading lubrication. This is serious!

8. Fault Codes: Check for diagnostic codes related to cylinder cutout, injector circuit faults, or injection timing issues.

Crucial Installation & Service Information

This is not a simple "plug-and-play" job. Proper installation is critical to avoid immediate failure or engine damage.

• Must Be Programmed: The most important step. Each new or remanufactured injector has a unique trim code or calibration code (a 4-7 digit number on the injector body). This code MUST be programmed into the engine's ECM (DDEC) using diagnostic software (e.g., Detroit Diesel Diagnostic Link - DDDL, or a capable aftermarket scanner). If not programmed, the engine will run poorly.

• Cleanliness is Critical: The fuel system is ultra-high precision. Any dirt introduced during installation can destroy the new injector or damage the fuel system. Clean the area meticulously.

• Replace Seals & Components: Always use a new installation kit. This includes:

• Upper and lower copper crush gaskets/seals (these are one-time-use only).

• O-rings and fuel seals.

• Spacer/Height Adjustment Shims (if required for your engine). The injector height is critical.

• Torque Specifications: Follow the exact, multi-step torque sequence and specifications from the service manual. Overtightening can distort the injector bore or damage the injector.

• Consider Replacing the Injector Hold-Down Clamp & Bolt: These are high-stress components and can fatigue.

  
  

• Preventive Maintenance Recommendations for Detroit Diesel EUI Injectors (R-5227170)

• Proactive maintenance is crucial to maximize injector life and prevent costly failures. These injectors typically last 400,000-750,000 miles with proper care.

• 1. Fuel Quality & Filtration (THE MOST IMPORTANT FACTOR)

• Use Ultra-Low Sulfur Diesel (ULSD): Always purchase from high-volume, reputable stations.

• Maintain Fuel Filters Religiously:

• Replace primary and secondary fuel filters at or before OEM intervals (typically 15,000-30,000 miles).

• Use OEM-spec or premium filters (Fleetguard, Donaldson, Baldwin). Never install cheap filters.

• Prime the system properly after filter changes to prevent air ingress.

• Drain Water Separator Daily: If equipped with a manual drain. Water is the #1 enemy of injectors.

• Consider Fuel Additives: A quality cetane booster and lubricity additive (e.g., Opti-Lube, Power Service) can improve atomization and protect against low-lubricity fuel, especially in winter.

• 2. Regular Engine Maintenance

• Maintain Clean Engine Oil & Filters: Contaminated oil can affect the injector's solenoid operation through the actuation system. Follow severe-service oil change intervals.

• Monitor Cooling System: Overheating destroys injectors. Maintain proper coolant levels, mixture, and replace coolant per OEM schedules.

• Operate the Engine Correctly: Avoid prolonged idling and "lugging" the engine at low RPMs under heavy load. Both can increase injector tip temperatures.

• 3. Monitoring & Diagnostics

• Regularly Scan for Codes: Use diagnostic software (DDDL, etc.) to check for pending or soft codes related to fuel trim or cylinder balance.

• Perform Injector Cut-Out Tests: This simple test (using diagnostic software) can identify a weak or failing injector before it causes major symptoms.

• Monitor Fuel Consumption: A sudden, unexplained increase in fuel consumption can indicate injector issues.

• Check for Fuel in Oil: At each oil check, smell the dipstick for diesel odor and note if oil level rises.

• 4. Storage & Downtime

• If the engine will sit for >30 days, use a biocide in the fuel tank to prevent microbial growth (algae) which clogs filters and injectors.

• Consider running the engine to operating temperature periodically during long storage.

• Replacement Installation Precautions & Step-by-Step Procedure

• ⚠️ PRE-INSTALLATION WARNINGS ⚠️

• SAFETY FIRST: Work on a cool engine. Wear safety glasses. Diesel fuel under high pressure can penetrate skin.

• Absolute Cleanliness: The injector bore is a cleanroom environment. Clean the valve cover area thoroughly before opening.

• Have All Parts & Tools Ready:

• New/reman injector R-5227170

• New installation kit (Detroit #23543207 or equivalent) – DO NOT REUSE SEALS

• Torque wrench (inch-pounds capable)

• Correct socket for injector hold-down clamp

• Diagnostic laptop/software READY FOR PROGRAMMING

• Record the new injector's calibration code before installation

Here is a summary of the main technical parameters for the Detroit Diesel R-5227170 Fuel Injector