Caterpillar C9 HEUI Pump: Part Numbers & Starting Problems
September 6, 2026
- Caterpillar C9 HEUI Pump: Part Numbers, Pressure Problems & No-Start Diagnosis
- Caterpillar C9 Marine Engine Parts
- send us the engine and pump information
- Why the C9 HEUI System Is Different
- A C9 That Cranks but Doesn't Start
- The Morning Start Is Fine. The Hot Restart Isn't.
- The Oil Dipstick Matters More Than You Might Think
- Caterpillar C9 HEUI Pump 384-0678 / 3840678
- 384-0678 / 3840678
- 20R-1636 / 20R1636
- Request a Caterpillar C9 HEUI pump quote
- What If the Pump on My Engine Has a Different Number?
- What About 319-0678 / 3190678?
- View Caterpillar 319-0678 / 3190678 Hydraulic Unit Injector Pump
- New Pump or Cat Reman?
- When the Pump Gets Blamed Too Quickly
- Could a HEUI Injector Cause Similar Trouble?
- The Engine Starts — Then Runs Rough
- If You're Removing the Pump, Photograph It First
- What We Need When You Ask for a C9 HEUI Pump
- A Few C9 HEUI Questions Worth Answering
- My C9 has fuel but won't start. Can the HEUI system still be the problem?
- Is 3840678 different from 384-0678?
- What is 20R1636?
- I found 3190678 online. Can I use that instead?
- 319-0678 / 3190678
- Why does my C9 restart badly when hot?
- Should I change all the HEUI injectors when I change the pump?
- Can you help if the pump number is unreadable?
- Need Help With a Caterpillar C9 HEUI Pump?
- Send Us Your C9 Details
- Request a Quote
- request@alfamarinespareparts.com
- Caterpillar Marine Engine Parts & Rebuild Kits
- Marine Spare Parts Catalogue
- Caterpillar 319-0678 / 3190678 Hydraulic Unit Injector Pump