At a Glance
- SKU: ST4353S
PRODUCT INFORMATION
Product Details
Filler Cap for KTI & DLH Hydraulic Power Units – ST4353S
Part Number – ST4353S | KTI / Monarch / DLH Compatible
| Product Type: | Hydraulic Reservoir Filler Cap |
| Fits Pump Brands: | KTI, DLH, Monarch, MTE, Bucher, Kyota (common 12V DC dump trailer power units) |
| Common Trailer Uses: | Dump trailers, tilt trailers, liftgates, snowplows, hoists, hydraulic jacks, and custom hydraulic control boxes. |
| Thread Style: | Standard coarse-thread cap for KTI/DLH plastic reservoirs |
| Thread Size (Most Common): | Approximately 1.75"–2.00" OD threads (KTI OEM) |
| Cap Diameter: | Approx. 2.5" across |
| Material: | Impact-resistant black polymer with molded grip |
| Includes Vent: | Non-vented cap (OEM match for most dump trailers) |
| Replaces / Cross Reference: | KTI: FC-100, ST4353S DLH: 4353 Series Monarch/Bucher: Equivalent filler plug used on 12V DC power-up/power-down units |
| Weight: | Approx. 0.05 lb |
Direct OEM-style replacement for hydraulic dump trailer power unit reservoirs.
About This Part
This is the exact filler cap used on most 12V hydraulic power units found in dump trailers, utility tilt trailers, and equipment trailers built with KTI, DLH, or Monarch/Bucher power packs. It threads directly onto the plastic hydraulic reservoir and seals the tank to prevent contamination of the hydraulic fluid.
These caps often get lost, cracked, or stripped during maintenance — and running a hydraulic unit without a proper cap can allow dust, water, and debris to enter the system, causing pump or valve failure. This part restores proper sealing to the reservoir without requiring replacement of the entire tank.
Compatible Power Units
- KTI (all standard plastic-tank models)
- DLH / Kyota
- Monarch / Bucher 12V power units
- MTE / Fenner-style units
- Replacement for many OEM dump trailer assemblies (Load Trail, PJ, Lamar, Iron Bull, Sure-Trac, Diamond C, etc.)
Reservoir Types
Fits the following reservoir styles:
- Square plastic 2" deep KTI tanks
- Plastic 7.5" x 7.5" dump trailer reservoirs
- Side-mount and top-mount hydraulic reservoir bottles
- Common “power up/power down” configurations
Features & Benefits
- OEM-style fit and thread profile
- Non-vented design matches factory configuration
- High-durability molded polymer
- Easy to install — hand-tighten only
- Protects hydraulic system from contaminants
- Affordable replacement part (keep a spare on hand)
Important Notes
- This cap is non-vented — if your OEM tank uses a vented cap, please verify before ordering.
- Always clean the reservoir neck before threading on a new cap.
- Works with 12V DC hydraulic power units using standard KTI/DLH-style plastic tanks.
Need help identifying your hydraulic pump or reservoir? Contact R & P Carriages — we can match your setup quickly.
Related Parts & Kits
Check fitment, measurements, and kit contents before ordering. Related parts may not be required for your repair.
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