DP310 equipment deserves a DP310-specific diagnosis. Familiar pump-family names are helpful; exact technical data does the actual work. Customers across the country can use our mail-in inquiry process to determine available testing, repair, rebuilding and calibration options for the exact unit.
What is the Delphi DP310 system?
Delphi DP310 is part of the broader series discussed in specialist Delphi training for DP200/DP210/DP310 injection-pump repair. Model differences affect calibration and components. Ask the shop to verify DP310 service eligibility before shipping, especially for unusual applications.
Common symptoms and what else to check
Hard starts, fuel leaks, rough running and fuel-delivery complaints may justify investigation, provided fuel supply and other engine conditions are assessed as well.
How to investigate a suspected DP310 pump problem
A reliable assessment begins with the complete model number and application. Service procedures, bench fixtures and settings should be selected for the exact unit.
Repair, rebuild or replacement: making the right call
A repair recommendation should distinguish an isolated defect from wider wear or contamination and consider parts support and final test requirements.
Other names and numbers to look for
The most useful search terms for this family include: Delphi DP310; Delphi DP310 pump; DP310 distributor injection pump.
DELPHI DP310 design, applications and diagnosis
How the DP310 Works
The DP310 has the same bones as the DP210, just on a stricter diet. It is an inlet-metered rotary pump: a vane transfer pump raises supply pressure, the governor meters fuel into a spinning rotor, rollers on an internal cam ring drive opposed plungers together, and the rotor hands each cylinder its charge in firing order.
What changed is precision. Emissions rules for the 1104D generation left a narrower calibration window, so wear an old DPA would shrug off can push a DP310 out of spec. Some versions carry extra electrical controls.
An electric stop solenoid opens the fuel path with the key on. Fuel lubricates everything inside.
Shop Talk: Tier 3 is the EPA’s third stage of off-road diesel emissions rules. Meeting it took tighter control of injection timing and quantity, which is why a DP310 calibration is less forgiving than its grandparents’.
What It Fits
| Make and model | Engine | Years | Notes |
|---|---|---|---|
| Tractors, telehandlers, loaders, gensets | Perkins 1104D-44T, 1104D-44TA | Electronic 1104D-E44 engines use a different system | |
| Cat machines with the C4.4 | Cat C4.4, mechanical | Electronic C4.4s do not use a DP310 | |
| JCB backhoes and telehandlers | JCB 444, mechanical | Look for a JCB 320/06 number |
More on our Perkins and Cat engine page.
Part Numbers We See
The DP310 can wear up to four different numbers, depending on who built the machine. The Delphi number on the pump plate starts 9520A and ends with a letter. Perkins numbers start 2644C. Cat uses its own three-dash-four format, and JCB numbers start 320/06.
Cross-Reference: Delphi, Perkins, Cat and JCB Numbers
| Number type | Pattern | Where to find it | Example |
|---|---|---|---|
| Delphi pump number | 9520A + digits + letter | Plate on the pump body | 9520A350G |
| Perkins part number | 2644C + digits | Pump label or Perkins parts book | 2644C348 |
| Cat part number | Three digits, dash, four digits | Cat parts book or label | 316-6964 |
| JCB part number | 320/06 + digits | JCB parts book or label | |
| Engine serial number | Perkins, Cat or JCB format | Engine plate | Lets us pin down the exact spec |
A Cat or JCB number and a Perkins number can look unrelated even when the pumps are close cousins. Close is not the same, though: calibrations differ by application, so never swap pumps on looks alone. Send every number you can read and let us match it.
Why DP310s Fail and the Symptoms
- Contaminated fuel. Dust, water and microbial sludge from jobsite tanks wear vanes, plungers and the rotor.
- Normal wear on a tight calibration. Small wear shows up as smoke and lost power sooner than on older pumps.
- Stop solenoid failure, which looks like a dead pump when it is often a dead coil.
- Seal leaks at the drive, throttle shaft and cover.
- Running with the shaft locked. Many 1104-series pumps use a shaft locking screw for removal and installation; starting the engine locked can damage the pump.
Symptoms:
- Cranks but will not fire
- Black smoke and lazy power under load
- White smoke on cold starts
- Hunting at idle
- Fuel weeping at the pump, or oil level rising
Owner’s Tip: Drain the water separator bowl into a clear jar. A layer of water or dark sludge on the bottom means the pump has been drinking it too. Fix the fuel source, or the rebuilt pump will drink it next.
Details that make a delphi dp310 inquiry useful
A DP310 inquiry should include both the pump’s identification and the full engine designation, since nearby Perkins and equipment families use several distinct fuel-system configurations. Photograph the mounting and control connections before removal. If the engine has a no-start complaint, share the fuel-supply checks already performed so a sound pump is not blamed for a restricted or aerated feed line.
Frequently asked questions
Can a Delphi DP310 injection pump be rebuilt?
Whether Delphi DP310 is a good repair candidate depends on sound housings, wear on precision components, the correct service parts and reliable model-specific test information. A leak, sticking from storage, or debris in the fuel may point to very different work. The right recommendation follows the evidence on the identified assembly—not the appearance of a similar pump. Discuss the exact unit.
Will a DP310 pump from another engine fit mine?
Identification trap with Delphi DP310: Similar castings do not establish interchange. Engine rating, governor and advance controls, electrical arrangements and part-number suffixes can change the specification. Compare the full tag and application before discussing replacement, calibration or installation. Use the identification guide.
Request Delphi DP310 Service Information: Start your repair inquiry
How mail-in service works | Browse pump families