Pilot hydraulic pressure weak or main valve spools not fully shifting on your Cat 318C, 320C or 320E? A worn 349-4087 pilot gear pump delivers insufficient pilot flow for the main valve spools to overcome their spring pre-load fully, causing all functions to respond partially or sluggishly. RITO supplies this complete gear pump assembly to restore full pilot flow on your Cat excavator.
Item NO.:
349-4087Order(MOQ):
1pcsPayment:
T/T, WESTERN UNION, CHINESE BANK,PAYPALProduct Origin:
JAPANShipping Port:
Huangpu,GuangzhouLead Time：
In Stock349-4087 Pilot Gear Pump Assembly for Caterpillar 318C, 320C, 320D, 320D2 and 320E excavators. The 349-4087 is a second-generation gear pump upgrade with an improved sealing interface compared to earlier Cat pilot pump designs. Precision gear mesh and lapped axial faces deliver consistent pilot flow from engine idle to full speed, ensuring reliable main control valve spool operation at all work conditions.
| Part Number | 349-4087 / 3494087 |
|---|---|
| Part Name | Pilot Gear Pump Assembly |
| Compatible Brand | Caterpillar |
| Applicable Models | 318C, 320C, 320D, 320D2, 320E Excavator |
| Application | Pilot circuit gear pump providing flow for main control valve spool actuation on 320-series excavators |
| Material | Precision alloy steel gear set and pump housing |
| Product Color | Metallic finish |
| Working Temperature | -25°C~+80°C |
| Key Function | Generates pilot hydraulic flow for full main control valve spool travel on Cat 318C / 320C-E |
| Condition | 100% New Aftermarket OEM Quality |
| Packaging | Wooden Case Reinforced Carton Neutral Packing Customized Box |
349-4087 features an improved axial seal interface versus earlier Cat pilot pump designs, reducing internal slip and maintaining rated pilot flow at low idle speed.
Gear mesh precision maintains pilot pressure stability from 800 rpm idle to full engine speed, preventing the pilot pressure dip at idle that causes hesitant valve spool engagement.
Covers 318C, 320C, 320D, 320D2 and 320E in one part number, addressing the full 320 generation range without model-specific variants.
Full assembly with all internal components and port threads, providing bolt-on replacement without disassembly of individual gears or bearing plates.
FAQ
Q: What are the symptoms of a failing 349-4087 pilot gear pump on 320D?
A: All machine functions slow simultaneously when engine is at idle, controls require more handle travel to achieve a given speed, pilot pressure reads below 3.5 MPa at idle on a gauge test, and warm-up period before controls become responsive increases progressively.
Q: Is 349-4087 a direct replacement for the 126-2016 pilot pump on 320C?
A: 349-4087 and 126-2016 are different pilot pump variants for Cat 320-series. Confirm which part number is fitted to your specific machine before ordering. Contact our technical team with the machine serial number if uncertain.
Q: Do I need to bleed the pilot circuit after fitting 349-4087?
A: Fill the gear pump case with clean hydraulic oil before connecting the case-drain line to prevent a dry start. Operate all functions slowly for 5 minutes after start-up to allow pilot circuit air to purge before applying full load.
Q: How to confirm 349-4087 is the correct pilot pump for my 320D?
A: Match the existing gear pump part number 349-4087 or 3494087 on the old pump body. Confirm machine is 318C, 320C, 320D, 320D2 or 320E. Provide serial number for cross-reference if uncertain.
Q: What quality options are available?
A: We provide original, OEM and high-quality aftermarket versions with stable supply capability.
Q:Why Choose RITO?
A:Listed Factory
Stable&Reliable Quality
OEM Factory for Chinese Top Excavator Brands
Supplier to Fortune 500 Companies
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