Three Decades · Diesel Mastery · Earned Precision
"From the dust of the earth and the steel of his hands, Harout forged a legacy. Where others saw iron, he saw intent; where others heard noise, he heard the heart of the machine. Three decades of sweat distilled into a single truth: Precision is not taught, it is earned. Today, the dream stands realized—a sanctuary of steam and steel where the tools that built the man now restore the machine."
— The Injector Library
Injectors We Service
From Volvo D-Series unit injectors to CAT MEUI assemblies — a documented gallery of every injector family on the bench. New entries posted as jobs are photographed and catalogued.
System Manufacturers
The companies that engineer and build the injection systems.
Engine / Machine Brands
The vehicle and equipment brands whose injectors we service.
— The Pump Library
Pumps We Service
Select a brand to browse the pumps we service. Photographs, model designations and OEM spec sheets — added as the workshop documents each restoration.
System Manufacturers
The companies that engineer and build the injection systems.
Engine / Machine Brands
The vehicle and equipment brands whose pumps we service.
— The Heart of the Machine
Injectors That Power Cities
From Volvo D-Series workhorses to CAT MEUI command systems — we service the heavy-duty atomizers that feed the engines lighting hospitals, ports and entire grids. A bad spray here is not a misfire. It is catastrophic loss of power, melted pistons, and silence on the line.
— Anatomy of the D16
The Volvo D-Series Unit Injector
Each D11/D13/D16 cylinder gets its own electronically controlled unit. We rebuild every internal — spring, plunger, nozzle — to OEM flow tolerances on a calibrated bench.
Coil Spring Stack
Cam-actuated return — calibrated to OEM rate.
Solenoid Connector
ECU command — micro-millisecond timing.
Hardened Body
1900-bar internal pressure rating.
Atomizing Nozzle Tip
0.01 mm spray geometry tolerance.
Common rail injection is the modern standard — a single high-pressure rail feeds every injector simultaneously, allowing precise electronic control over timing, quantity, and multiple injection events per cycle. This technology delivers cleaner combustion, lower emissions, and superior fuel economy. At HMD, we diagnose, rebuild, and recalibrate every component in the common rail circuit — from the high-pressure pump and rail pressure sensor to each individual injector — restoring factory-level performance to the systems that keep critical infrastructure running.
Solenoid Valve
Electromagnetic actuation — sub-millisecond response times.
Nozzle Assembly
Multi-hole precision spray geometry, 0.01 mm tolerance.
Control Chamber
Hydraulic servo — rail pressure up to 2000 bar.
Fuel Return
Back-leak bench tested to OEM thresholds.
Volvo D-Series
D11 · D13 · D16 — unit injectors and common-rail systems calibrated for marine and heavy-haul applications.
Caterpillar MEUI
Mechanically actuated, electronically controlled. The brain and brawn of CAT 3406, C15, and 3500 series powerplants.
Industrial Gensets
From 27 kVA compact units to 1,500 kVA prime power — we service the full spectrum of generator injection systems across continents.
— The Conductor
Pumps That Set the Tempo
Timing is the difference between power and failure. We rebuild the heart that meters every drop — from rotary distributor pumps to the cathedral-sized inline Bosch units that drive industry.
Inline Bosch Pumps
Rotary Distributor Pumps
Inline Bosch Pumps
01 / 02A · P · MW · PE Series · Marine & Genset
Massive multi-element pumps — one plunger per cylinder, each a miniature engine of its own. We rebuild the cam-driven heart of the largest commercial diesels with bench accuracy that returns the engine to the day it left the factory floor.
Rotary Distributor Pumps
02 / 02Perkins · Delphi · DPA · DPS
Single-element wonders metering fuel for every cylinder through one rotating head. Timing tolerances measured in degrees of crankshaft rotation. We strip, lap, and re-shim each governor to original calibration sheets — no shortcuts.
— The Forensic Lab
Diagnostics, Not Guesses
The bench does not lie. Specialized test rigs, calibrated tooling, and three decades of pattern recognition turn ambiguous engine symptoms into measurable, fixable data.
12-Cylinder Pump Test Bench
Full-scale diesel pump test bench with 12-cylinder output rig. Simulates real engine conditions across full RPM and load ranges for precise calibration of inline and rotary pumps.
Hartridge EUI/EUP Injector Tester
Precision electronic unit injector and unit pump tester by Hartridge. Measures spray pattern, back-leak, opening pressure, and solenoid response for all major EUI/EUP systems.
Common Rail Diagnostic Bench
High-pressure common rail test bench with integrated display and precision gauges. Tests injector response curves, rail pressure integrity, and leak-back rates for modern diesel injection systems.
Spray Pattern Forensics
High-pressure bench testing visualizes the exact conical geometry of every injector spray. We catch dribble, asymmetry, and flow drift invisible to the field tech.
OEM Calibration Sheets
Every pump and injector is returned to its original factory test specification — verified across full RPM and load ranges, not a single spot check.
Common Rail Integrity
Leak-back tests, response curves, and solenoid resistance mapping for modern electronic injection systems on industrial and marine duty cycles.
Documented Restoration
Every job ships with its before / after data — a forensic record you can hand to insurance, fleet managers, or the next mechanic down the line.
— Our Legacy
Thirty Years. One Pair of Hands.
HMD was not built in a boardroom. It was built bolt by bolt by a man who refused to leave a machine broken — and who refused to be anything less than the best in his field.
First Wrench
Harout begins his apprenticeship — learning the silence and song of every diesel pump by hand.
Master of the Bench
Decade of field work crystallizes into a specialty: rotary and inline injection systems no one else would touch.
Heavy Industrial
Service expands to genset, marine, and prime power — the engines that keep cities lit through the night.
HMD Workshop
A sanctuary of steam and steel. The dream realized — built with the same tools that built the man.