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5422890 Hydraulic Lock Piston Seal Kit For MST M542 M544 | Ruijueparts

5422890 Hydraulic Lock Piston Seal Kit For MST M542 M544 | Ruijueparts

Regular price $16.42
Regular price Sale price $16.42
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Availability1000 in stock

Volume discounts available · Minimum order quantities apply for bulk pricing

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SKU: 5422890
Vendor: RuiJueParts

Shipping & Returns

Shipping:
- Standard models take 1-3 business days.
- Bulk orders take 3-7 business days.
- For urgent orders, please contact our sales team. [Email: info@ruijueparts.com]

Returns:
We accept returns within 30 days of purchase. Learn more—return policy

Packaging details

PP bag, carton

Place of Origin

China

Payment terms

L/C, T/T, Western Union, MoneyGram

Performance

Oil Sealing

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Product Description

5422890 is an aftermarket piston seal kit for the hydraulic lock of the rear carriage on MST backhoe loaders. It is used to reseal the piston within the locking mechanism that secures the rear excavator carriage assembly; it is not a standard boom, dipper, bucket or hydraulic control-valve seal kit. Published catalogues identify this application for MST M542 and M544, while other trade listings also include selected Plus versions. Confirm the machine serial number, rear-carriage lock assembly and installed reference before ordering. Ruijueparts supports part-number checking, mixed-SKU enquiries and neutral or customer-specified packaging.


Item specifics

Part Number: 5422890
Fits Models: M542, M544
Brand: MASTAS replacement
Type: Aftermarket Hydraulic Lock Piston Seal Kit
Rear Carriage Lock Repair Seal Kit
Application:
  • For service of the rear-carriage hydraulic locking mechanism on MST-compatible backhoe loaders. Repair teams can remove, inspect, reseal and reinstall the confirmed hydraulic-lock piston assembly. One kit is required per piston; verify the lock assembly and serial number before purchase.
  • Backhoe Loaders: M542, M544
Size: Standard Size


FAQ

  • Q1: What does MST 5422890 repair?
    A: It reseals the piston of the hydraulic locking mechanism used with the rear carriage of applicable MST backhoe loaders.
  • Q2: Is 5422890 a normal hydraulic cylinder seal kit?
    A: No. It is a dedicated hydraulic-lock piston kit. Do not substitute it for boom, dipper, bucket, stabilizer or loader-lift cylinder seal kits.
  • Q3: Is one 5422890 kit enough for the complete locking assembly?
    A:
    Published application information states that one kit is used per hydraulic-lock piston. Confirm how many lock pistons are fitted to your specific machine before ordering.

Why choose Ruijueparts

Lower cost — honest trade-off

Our aftermarket seal kits deliver a practical, cost-effective solution without compromising on real-world performance. We offer a lower upfront cost and reliable sealing for your daily maintenance and repair needs.

Extensive part number range

We stock seal kits across CAT, Komatsu, Volvo, JCB, Hitachi, Doosan, John Deere, Kubota, and 10+ other brands—one supplier for your whole fleet.

Flexible packaging options

Ship under RuijueParts branding, neutral (unbranded) packaging, or your own private label. Suitable for resellers and distributors.

Customization Service

When genuine OEM seals are out of production for your old machinery, we can custom-make oil seals using your dimensions or our engineer-recommended specifications.

Wholesale & OEM bulk orders

Ship under RuijueParts branding, neutral (unbranded) packaging, or your own private label. Suitable for resellers and distributors.

Warranty on request

Volume pricing for repair shops, dealers, and fleet operators. Get a quote via our website or WhatsApp: +86 13692100161.

When budget aftermarket makes sense

OEM seal kits are the right choice when machinery is under active warranty, operating at peak duty cycles, or when failure risk is unacceptably high. Budget aftermarket—like Ruijue Parts—makes sense in these common scenarios:

Older or end-of-life equipment

When a machine is aging out of your fleet, OEM parts cost more than the job warrants. A budget kit extends service life without over-investing.

Secondary or backup machines

For machines used infrequently or on lower-intensity tasks, premium OEM pricing may not be justified.

OEM parts unavailable or on long lead time

When OEM stock is out or delivery takes weeks, an available aftermarket kit gets your machine running now.

Fleet maintenance on a fixed budget

Repair shops and fleet managers running high volumes of machines often balance OEM and aftermarket across their portfolio based on criticality.

Installation guide

1. Depressurize the hydraulic system

Fully retract the cylinder and relieve system pressure before disassembly. Never work on a pressurized circuit.

2. Remove and disassemble the cylinder

Remove from the machine. Unthread the gland nut and withdraw the piston rod carefully to avoid surface damage.

3. Clean all components thoroughly

Clean the bore, rod, and all metal parts with a lint-free cloth. Contamination introduced during reassembly accelerates seal wear—this step is especially important for budget-grade seals.

4. Inspect the rod and bore

Check for scoring or pitting. Budget seals are more sensitive to surface imperfections—address rod damage before fitting new seals.

5. Install the seal kit

Lightly coat each seal with clean hydraulic fluid before installation. Use proper seal drivers — not screwdrivers or sharp tools — to avoid nicking the sealing lip.

6. Reassemble and pressure test

Torque the gland nut to spec and cycle the hydraulic system under no-load conditions. Inspect for leaks before returning the machine to service.

Maintenance tips

Inspect every 250–500 hours

Budget-grade seals may have shorter service intervals than OEM. Inspect rod seals for moisture, oil film, or weeping more frequently and replace proactively.

Keep hydraulic fluid clean

Contaminated fluid degrades seals faster — this applies especially to non-OEM materials. Replace fluid and filters on schedule.

Protect exposed rod surfaces

When storing equipment with cylinders extended, protect rod surfaces from corrosion and debris to preserve wiper seal life.

Ensure Proper Installation

Avoid using sharp tools during assembly to prevent nicks or scores on the seal lips. Pre-lubricating all components with clean hydraulic oil is recommended to ensure a smooth fit into the cylinder grooves.

Reduce Downtime with Reliable Seals.

Click "Add to Cart" for immediate dispatch, or contact our team for bulk pricing and wholesale support.

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