25371 Stellar Crane 4-Way Solenoid Valve Kit - Tandem Center - 12V Double Solenoid - Boom Directional Control

25371 Stellar Crane 4-Way Solenoid Valve

Restore your crane's boom functions. This is the complete valve + coils kit for Stellar truck-mounted cranes — the 4-way, 3-position directional control valve that routes hydraulic fluid to extend, retract, and rotate the boom. When this valve fails, the crane loses directional control and the boom is dead. Stellar part number 25371. Kit includes the valve cartridge AND both 12V solenoid coils — everything you need, nothing else to buy.

The Problem

You hit the joystick to extend the boom — nothing happens. Or the boom extends but won't retract. Or the crane functions are sluggish, erratic, or stuck in one direction. The 4-way directional control valve is the heart of your crane's hydraulic control system. It's a cartridge valve with two solenoid coils — one for each direction. When the operator commands a boom function, the controller energizes one coil, shifting the spool to route oil from the pump to the correct port (A or B) on the hydraulic cylinder.

When the valve or a coil fails, the crane loses one or more boom functions. The service truck is generating $150+ per hour in billable work, and right now the crane is an expensive paperweight bolted to the back.

You call the Stellar dealer. They want $215–$250 for the valve cartridge — and they often sell it without the coils. The coils are another $75–$100 each. By the time you have everything you need, you're $350+ deep and you've waited a week for shipping.

The Solution

We sell the complete kit — valve cartridge . That's the valve for less than what the Stellar dealer charges for the valve alone. Drop the cartridge into the existing VC08-4 cavity, thread on the coils, plug in the Deutsch connectors, and you're lifting again.

What's Included

• 1× 4-Way Directional Control Valve Cartridge — Tandem Center spool configuration
• O-rings / Seals — as supplied with the cartridge

How It Works — Tandem Center Explained

This valve has three positions controlled by two solenoid coils:

• Position 1 (Coil A energized): Pump pressure routes to Port A, Port B returns to tank → boom extends (or rotates one direction)
• Position 2 (Coil B energized): Pump pressure routes to Port B, Port A returns to tank → boom retracts (or rotates the other direction)
• Neutral (No coil energized): Tandem Center — pump flow passes through to tank (no pressure buildup), Ports A and B are blocked (boom holds position)

The Tandem Center configuration is critical: in neutral, the pump unloads to tank (reducing heat and fuel consumption), while ports A and B stay blocked (the boom doesn't drift under load). Do not substitute an Open Center spool — open center allows all ports to connect in neutral, which means the boom will drift down under load. The Stellar 25371 is a Tandem Center valve.

Specifications

• Stellar OEM Part Number: 25371 (also G04571 stamped on hex)
• Type: 4-Way, 3-Position Directional Control Valve (Double Solenoid)
• Spool: Tandem Center (P→T in neutral; A & B blocked)
• Cavity: VC08-4 (Standard 4-way cavity)
• Flow Rating: 3 GPM Max (Size 08)
• Function: Boom extend/retract, rotate, outrigger control
• Condition: Brand New — cartridge + both coils

⚠️ Tandem Center vs Open Center — Verify Before Ordering

The Stellar 25371 is a Tandem Center valve. In the tandem center configuration:

• Neutral: Pump flows to tank (P→T connected). Ports A and B are blocked — the boom holds its position.

An Open Center valve is different:

• Neutral: All ports are open (P, T, A, B all connected). The boom will drift down under load.

Most Stellar cranes use Tandem Center. If you're unsure which configuration your crane requires, remove the existing cartridge and check the spool type markings, or contact us with your crane model and serial number. Installing the wrong spool type will cause the boom to drift, overheat the hydraulic system, or create dangerous uncontrolled movement.

Identification

• Location: The valve cartridge is threaded into the hydraulic valve manifold, typically located at the base of the crane or on the valve bank
• Visual ID: Hex-shaped cartridge body threaded into the manifold, with two solenoid coils stacked on top (one for each direction)
• Part Number: Look for "25371" or "G04571" stamped on the hex body of the cartridge
• Coil ID: Size 08 coils with Deutsch electrical connectors
• Cavity: VC08-4 standard 4-way cartridge cavity

Compatible Equipment

This valve kit fits the following Stellar crane models (verify part number 25371 in your manual):

• Stellar 2200 Series
• Stellar 3200 Series
• Stellar 4500 Series
• Stellar 6620 Series
• Other Stellar cranes using PN 25371 / G04571 (verify in service manual)

⚠️ This valve is used in multiple positions on the crane manifold (extend/retract, rotate, outriggers). The same valve may be used in multiple positions. Verify which function has failed and replace the corresponding cartridge + coils.

Symptoms of a Failed Directional Control Valve

• No boom movement: Joystick commands have no effect — the valve spool is stuck or a coil is dead
• One direction only: Boom extends but won't retract (or vice versa) — one coil has failed
• Sluggish or weak movement: Boom moves slowly under load — spool is partially stuck or internal bypass leaking
• Boom drifts when controls are neutral: Spool not returning to center — worn centering springs or wrong spool type installed
• Hydraulic fluid overheating: Valve is bypassing internally — oil is recirculating through the valve instead of doing work
• Erratic crane behavior: Functions work intermittently — electrical connection issue at the coil (check Deutsch connectors for corrosion)
• Coil is burned out: Coil body is discolored, smells burnt, or has no continuity when tested with a multimeter

Diagnosis — Is It the Valve or the Coil?

Before replacing the entire kit, you can diagnose which component has failed:

1. Check the coils first — they're the most common failure. Use a multimeter to test coil resistance. A good 12V DC coil should read approximately 6–12 ohms. An open circuit (infinite resistance) means the coil is burned out.
2. Swap coils — if one direction works but the other doesn't, swap the two coils. If the dead direction follows the coil, the coil is bad. If the dead direction stays the same, the valve spool is the problem.
3. Listen for the click — when commanding a boom function, listen at the valve manifold. If you hear the coil click but the boom doesn't move, the spool is stuck (contamination, scoring, or broken centering spring).
4. Check power at the coil — use a voltmeter to verify 12V at the Deutsch connector when the function is commanded. If no voltage, the problem is upstream (controller, wiring, or operator input device).

Why Buy From Trenchwell?

• Complete Kit — Valve + Both Coils: Stellar often sells the valve without coils, or charges $75–$100 per coil separately. Our kit includes the valve cartridge AND both 12V solenoid coils for one price. Nothing else to buy.
• Save $80+: The Stellar dealer charges $215–$250 for the valve alone. Add two coils at dealer pricing and you're $350+. Our complete kit is $269.
• Tandem Center — Correct Configuration: This is the Tandem Center spool that Stellar 25371 calls for. Not an open center substitute that will let your boom drift.
• In Stock, Ships Now: Crane is dead, crew is idle, jobs are waiting. We have it on the shelf.
• Plug-and-Play: VC08-4 standard cavity, Deutsch coil connectors. Thread the cartridge into the manifold, thread on the coils, plug in the connectors, bleed the circuit, and you're lifting again.

Installation Notes

• Shut down the crane and the truck engine
• Release all hydraulic pressure — cycle the controls with the engine off to depressurize the system
• Locate the valve cartridge on the manifold — identify which cartridge corresponds to the failed function
• Disconnect the Deutsch electrical connectors from both coils
• Unthread the two coils from the cartridge
• Unthread the cartridge from the manifold (deep socket or wrench on the hex)
• Inspect the manifold cavity bore — clean out any debris or contamination
• Install new O-rings on the new cartridge (check that factory-supplied seals are in place)
• Thread the new cartridge into the manifold cavity — hand-start, then torque to spec
• Thread both new coils onto the cartridge
• Reconnect the Deutsch electrical connectors — verify the correct coil corresponds to the correct direction
• Start the engine and test each function: extend, retract, and neutral (boom should hold position in neutral)
• Check for leaks at the cartridge and coil connections
• Verify smooth, responsive operation in both directions under load

Frequently Asked Questions

Can I just replace the coils without replacing the valve cartridge?
Yes — if diagnosis confirms the coils are the problem (no continuity, burn damage) and the spool moves freely, you can replace just the coils. However, if the valve has been operating with a burned coil (allowing the spool to stick in one position or not center properly), there may be internal wear or scoring on the spool. If you replace the coils and the function is still sluggish or erratic, the cartridge needs to be replaced too. Our kit includes both so you can do the job once.

What's the difference between Tandem Center and Open Center?
Tandem Center: In neutral, pump flow goes to tank (P→T) and ports A & B are blocked. The boom holds its position without drifting. Open Center: In neutral, all ports are interconnected. The boom will drift down under load. Most Stellar cranes use Tandem Center. Installing the wrong type is dangerous — confirm your configuration before ordering.

I have multiple boom functions that aren't working — do I need multiple valves?
Each crane function (extend/retract, rotate left/right, outrigger up/down) typically has its own separate 4-way valve cartridge in the manifold. If multiple functions have failed simultaneously, it's more likely an upstream issue (pump pressure, controller, power supply) rather than multiple cartridges failing at once. Diagnose the root cause before replacing individual valves.

The boom drifts down slowly in neutral — bad valve?
Possibly. If the valve spool isn't centering properly, oil can bypass internally. But boom drift can also be caused by a worn cylinder seal, a leaking check valve (counterbalance valve), or an overheated hydraulic system with thinner-than-spec oil. Check the cylinder for external leaks first. If the cylinder is tight, the valve is likely the culprit.