20R-3815 -Genuine CAT Fuel Pump

Description

CAT 20R-3815 Fuel Injection Pump - Genuine Caterpillar Fuel Injection Pump for C6.6 Engines

The CAT 20R-3815 is a genuine Caterpillar high-pressure fuel injection pump for the C6.6. It supplies pressurized, metered fuel to the injection system.

Key Functions:

- Supplies high-pressure, metered fuel to the C6.6 injection system

Fitment & Specifications:

- Application: CAT C6.6 (Perkins-based; cross 2641A407 / 2641A312)
- Machines: 924H, 938H, 953D, 963D, D5R, D6K, D6N, IT38H, PL61 (confirm by engine serial)

Verify fitment with us before ordering to ensure the correct part for your application.

Purpose of the Part

It's the pump that builds and meters the fuel pressure the C6.6 injection system runs on. A worn or failing pump shows as hard starting, low power, stalling, or a no-start when it can't hold pressure.

Issue Symptoms / When to Replace

- Hard start or no-start
- Low power, stalling, or surging
- Loss of fuel pressure
- Fuel leak at the pump

Diagnose with CAT ET and check actual fuel pressure before condemning the pump.

Brand Information

A genuine CAT 20R-3815 is built to the C6.6's fuel-pressure and metering spec, which is what a common-rail-era injection system depends on to start and make power. Caterpillar builds engines, machines, and components worldwide.

Installation Notes

- Prime and bleed the fuel system before start so the pump isn't run dry or airlocked.
- Confirm the correct pump timing/setup for your engine serial before install, and keep the fuel system clean with new seals - injection pumps don't tolerate contamination.

How to Identify an OEM Part

Genuine CAT injection pumps are marked with the CAT part number.

Why buy from Wisent Parts
  • ⏱️
    Fast shipping
    Orders before 12PM EST ship same business day.
  • 🛡️
    180-day warranty
    All parts covered from delivery date.
  • ↩️
    Easy returns
    30-day returns.
  • ✅
    Verify fitment
    Send VIN/ESN and we’ll confirm.

Shop with confidence

Warranty & Return Information
Warranty Information

Wisent Parts offers a 180-day warranty on all parts from the date of delivery. This warranty covers orders placed directly through our website. If a part fails during this period, we’re here to help - whether it’s a replacement, repair, or refund. For full details, refer to the Warranty page.

Return Information

Wisent Parts accepts returns within 30 days of delivery. All returns are subject to a restocking fee. To qualify, parts must be unused and in their original condition. For full return instructions and restocking fee details, please refer to the Returns page.